- Email: [email protected]
Reducing benzodiazepine self-administration with contingent reinforcement
Addicriw Behauiors. Vol. 4. pp. 245 lo 252 0 Rrgamon Press Ltd 1979. Printed in Great Britain
0306.4603/79/0701-0245S02.00fil
REDUCING BENZODIAZEPINE SELF-ADMINISTRATION WITH CONTINGENT REINFORCEMENT* MAXINE L. STITZBR, GEORGE E. BIGEL~W and IRA LIEBSON Department of Psychiatry, Baltimore City Hospitals and Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine Abstract-The purpose of the present study was to determine whether drug self-administration by methadone maintenance clients can be influenced by offering methadone clinic privileges contingent upon reductions in drug use, and to compare the reinforcing efficacy in this regard of two different clinic privileges. Eight methadone maintenance clients who had histories of supplemental benzodiazepine use participated. In order to transfer illicit drug use to the treatment clinic, clients were prescribed diazepam, 20mg/day, at the methadone clinic dispensary. Following assessment of baseline diazepam use, clients were offered, during 6-week blocks of time, either the chance to obtain a single methadone take-home dose or the chance to self-regulate their methadone dose for a single day. These privileges were contingent upon refusing prescribed diazepam at the clinic. During baseline weeks, 95.6% of available diazepam doses were requested. When take-home privileges were available, only 11.2% of diazepam doses were requested, while when dose self-control was available, 69.7% of doses were requested. The study showed that the supplemental drug use of methadone maintenance clients can be influenced by clinic privileges which are available contingent upon reductions of drug use. The medication take-home privilege was more effective as a reinforcer than was limited methadone dosage selfcontrol. Methadone clinic privileges can be used as intervention tools to promote desirable therapeutic behavior change in drug addicts, and in particular to promote reductions in supplemental drug use.
Methadone maintenance has been the treatment of choice for narcotics addiction for a number of years (Dole & Nyswander, 1965), and has demonstrated efficacy in reducing illicit heroin use and promoting improved social adjustment among addicts (Dole et al., 1968; Gearing, 1974). Nevertheless, many addicts have long-standing deficits in social and personal adjustment which do not abate after entry into methadone treatment. Furthermore, many addicts continue to abuse various drugs during their enrollment in methadone maintenance treatment. Thus, the need for ancillary treatment in addition to methadone is frequently emphasized (Brill & Chambers, 1973; Dole & Nyswander, 1976; Goldstein, 1976). Contingency management procedures including token economies and individualized contingency contracting have achieved widespread application in a variety of mental health fields and have been enormously .successful in promoting positive therapeutic outcomes (Leitenberg, 1976). In the area of drug abuse, however, these promising techniques have received relatively little attention and evaluation (GStestam et al., 1975). Several investigators have utilized contingency management programs with addicts who were living on inpatient wards. These programs increased participation in ward activities and promoted other socially acceptable behaviors (Eriksson et al., 1975; Glicksman et al., 1971; Melin & Gotestam, 1973; Melin ef al., 1975; O’Brien et al., 1971). Contingency management prodecures have also been applied in outpatient settings to promote improved social and personal adjustment (Bigelow ef al., 1979; Boudin et al., 1977; Hall et al., 1977). In addition, several investigators have described the use of contingency contracting or contingent incentive procedures specifically to promote reductions in use of drugs and alcohol among addict clients (Bigelow et al., 1976; Boudin, 1972; Hall et al., 1977; Liebson et al., 1973). Methadone maintenance clinics provide a potentially useful site for instituting vigorous contingency management intervention programs with addicts. Because methadone is a potent reinforcer which maintains addict clients in treatment, the methadone *This research was supported by USPHS Grant No. DA-01472 and Research Scientist Development Award No. DA-00050 from the National Institute on Drug Abuse. Send reprint requests to: Dr M. Stitzer, Baltimore City Hospitals, D-S-West, 4940 Eastern Avenue, Baltimore, MD 21224. U.S.A. 245
MANNEL. STITZER, GEORGE E. BIGELOW and IRA LIEBSON
246
clinic allows relatively long term contact with a drug abusing patient population. Furthermore, treatment clinic services and program privileges have potential value as reinforcers for use in contingent therapeutic arrangements (Hall et al., 1977; Stitzer & Bigelow, 1978; Yen, 1974). Methadone take-home medication (Bigelow et al., 1976; Stitzer et al., 1977) and limited methadone dosage self-control by clients (Stitzer et al., 1979) have both been identified as program privileges with potential value for promoting therapeutic change when used in contingent arrangements. Drug ingestion is ultimately the behaviour of central concern for drug abuse treatment. Furthermore, continued supplemental use of drugs by methadone maintenance clients is almost universally reported, the two drug classes which are notable for their continued use by a substantial portion of methadone maintenance clients being heroin (Bigelow et al., 1976; Goldstein et al., 1977; Ling et al., 1978; Woody et al., 1975a) and benzodiazepines (Bigelow et al., 1976; Woody et al., 1975a, 1975b). It would be of particular clinical relevence to assess the extent to which drug ingestion can be influenced by program privileges which are made available at the clinic in contingent arrangements. The purpose of the present study is to determine whether program privileges can be used to influence drug self-administration at the methadone clinic and to compare the reinforcing efficacy in this regard of two different program privileges which previous research suggests could act as reinforcers for methadone maintenance clients: methadone take-home medication and limited control over methadone dosage. METHODS Subjects
Eight clients enrolled in a methadone maintenance treatment research clinic participated. Table 1 shows demographic characteristics of the study participants. Clients tended to have poor personal and social adjustment: most were unemployed, had long histories of narcotics use and supplemented their methadone with a variety of drugs. All study participants had histories of supplementary benzodiazepine use as indicated by clinical interview, while current benzodiazepine use was verified by urinalysis tests. Setting
Experiments were conducted in an outpatient methadone maintenance research clinic with an enrollment of about 40 clients. Prior to enrolling in the research clinic, clients gave their informed consent to participate in studies in which they would be offered incentives whose delivery might depend upon their drug use or other behaviors. General clinic procedures
Clients reported to the methadone clinic 7 days a week and ingested methadone under nursing supervision. Urine samples were collected twice weekly (Monday and Table
1. Characteristics
Age
Race*
Years of education
JB WC MC cw GT WB DW MJ
19 30 28 26 23 39 30 21
W W W W W B W W
11 I1 II II II 8 12 12
Average
27.75
Client
*W = tunemp
10.9
Caucasian; B = Black. = unemployed; pt = part time; ft = full time
of study
participants
Years of continuous narcotics use 4 II I 5 9 13 13 10 9.
Employmentt during study unemp unemp unemp Pt unemp unemp unemp ft
Methadone dose (mg) 60 50 80 50 50 60 50 50 56.25
Contingent reduction of benzodiazepines
247
Friday). All samples were routinely analyzed for methadone, opiates (heroin, morphine, codeine, meperidine, and hydromorphone), quinine (which was considered in data analyses as evidence of opiate use), barbiturates (phenobarbital, unspecified barbiturates), nonbarbiturate sedatives (meprobamate, methaqualone, glutethimide, ethchlorvynol), stimulants (cocaine, amphetamine, methamphetamine, phenmetrazine) and phenothiazines, phenytoin and propoxyphene which are grouped in a single category called “other drugs” for purposes of data analysis. Study procedures
Each study participant received a prescription for diazepam, 20 mg/day from the clinic. The therapeutic rationale for prescribing diazepam was to shift illicit use of benzodiazepines by these clients to the treatment clinic. The experimental rationale was to bring a portion of the benzodiazepine use of these clients under direct experimental observation and control at the research clinic. If a client requested diazepam on a given day he was required to swallow one 10 mg tablet at the dispensary window under nursing supervision. He then received the second 10mg tablet to ingest later in the day as needed. Clients were free to request or decline diazepam daily throughout the study. Contingent and noncontingent periods, generally of 6-week duration, alternated throughout the study. During noncontingent or baseline weeks no consequences were attached to diazepam request. During contingent weeks, clients could receive program privileges by refusing diazepam at the clinic dispensary. The privileges offered were methadone take-home medication or limited methadone dosage self-regulation. The former consisted of the delivery to the client of a bottle containing his regular methadone dose to be ingested on the following day at the time of the usual clinic visit. The latter consisted of the opportunity to alter the stable methadone dose on a single day by as much as f 20 mg or + 50% of the stable dose, whichever was smaller. All study participants had been exposed to the dose self-regulation procedure during a previous experiment (Stitzer et al., 1979) and all had taken advantage of the self-regulation opportunity by increasing their dose. No study clients had received take-homes at this clinic except on occasional holidays when the clinic was closed, but all had been enrolled previously in other methadone programs and it is therefore likely that participants had been exposed to take-home privileges in the past. For 5 study participants take-home privileges were available for diazepam refusal during the first contingent period while dose self-control was available during the second contingent period. The remaining 3 clients were exposed to the 2 program privilege reinforcers in the reverse order. During contingent weeks a program privilege (take-home medication or dosage selfcontrol) could generally be obtained by refusing diazepam for 3 or 4 consecutive days. A maximum of 2 privileges could be obtained each week by refusing diazepam 7 consecutive days. Privileges earned by diazepam refusal were delivered one at a time after completion of the diazepam refusal requirements and could not be “saved up”. That is, each privilege had to be used before credit was given toward earning the next privilege. If a client requested diazepam at any time during contingent weeks of the study, 4 consecutive days of diazepam refusal were required to obtain the next privilege. During the first week of each contingent phase, a more dense schedule of reinforcer availability was in effect. Clients could obtain a maximum of three privileges by diazepam refusal during the first of the 6 contingent weeks. Since clients had the option of coming to the clinic to request diazepam even on days when they received a methadone take-home dose, these take home days were counted as a day of diazepam refusal toward the next available privilege. Instructions
to subjects
Study participants were told that during certain portions of the experiment they would be able to choose between taking diazepam at the clinic and receiving a different program privilege. The rules governing program privileges and how these could be obtained
248
MAXINE L. STITZER,GEORGEE. BIGEL~W and IRA LIEBSON
by diazepam refusal were explained in detail. Verbal and written instructions indicated that the diazepam prescription would be available throughout the experiment, that the decision to use the prescription was always’ up to the client and that the point of the study was to see what clients choose when offered the choice between diazepam and other program privileges. RESULTS
Figure 1 shows the number of 10 mg diazepam doses requested at the clinic dispensary during each week of the study by individual study participants. During all baseline weeks combined, 95.6% of available diazepam doses were requested. When the takehome reinforcement was available, virtually all clients refused diazepam regularly in order to receive these privileges. The only exceptions were MC who did not refuse diazepam until the third week of the take-home contingency period and GT whose diazepam refusal was variable throughout the contingent period. Overall only 11.2% of available diazepam doses were requested when refusal resulted in take-home privileges. In contrast, only one client (WB) refused diazepams consistently in order to obtain dose self-regulation opportunities. Typically, clients refused some or all diazepam doses in the first week of the methadone dose sell-control contingent period (CW, GT, DW, MJ) then returned to regular diazepam use. Overall, 69.7% of available diazepam doses were requested when refusal resulted in methadone dose self-control opportunities. Clients might continue benzodiazepine use outside the clinic even if they refused diazepam at the clinic dispensary. Benzodiazepine urinalysis results would reveal whether clients discontinued benzodiazepine use entirely or continued some use outside the clinic. Benzodiazepine urinalysis results are presented in Table 3. There were 9 instances where all diazepam doses were refused for 2 weeks or longer (one instance each for JB, WC, CW, DW, and MJ: 2 instances each for MC and WB). Since. it would take at least 2 weeks for benzodiazepines to clear from the body following abrupt cessation of their use, we could not expect to see clean urines before this amount of time. Only 3 of these instances of discontinued diazepam use at the clinic are correlated with any benzodiazepine free urinalysis tests (MC during methadone dosage self-control contingency, CW at the end of the take home contingency and WB following the end of the methadone dose self-control contingency). In general, then, urinalysis tests indicated that most clients may have engaged in some benzodiazepine use outside the clinic during periods of time when they were refusing diazepam at the clinic dispensary. However, the urinalysis test.gives no information about the frequency or ,quantity of use. In fact, ingestion of a single low dose of benzodiazepines might be detected in urine for up to 2 weeks. As shown in Table 2, study participants used supplemental drugs from multiple drug classes in addition to benzodiazepines. Although the observed level of drug use varied considerably across individuals, the pattern of use was similar in that all but one (WB) used a variety of sedative and miscellaneous drugs in addition to benzodiazepines and none of these clients used stimulants to any significant extent. Only client WB showed substantial amounts of opiate use. Analysis of all drug positive indicators obtained during the study for the entire group revealed that phenothiazine positives accounted for the largest single percentage of drug positive indicators (29.6% of positive indicators) with unspecified barbiturate the second most prevalent class (24.6% of positive indicators) and phenobarbital the third” most prevalent (13.6% of positive indicators). Phenothiazine positives are possibly due to the use of Phenergan (promethazine) a sedative with antihistaminic and antiemetic properties which is purported to “boost” the effects of methadone. An analysis of drug use over time revealed no noticeable trend in the frequency or type of drug use during contingent and noncontingent study periods or trends over the course of the entire study. DISCUSSiON
Supplementary drug use is a significant clinical problem among a portion of done maintenance clients. In reviewing urinalysis result of general methadone
metha-
clinic
Contingent reduction of benzodiazepines TAKE
‘4-
HOME
-1.
DOSE
CONTROL
:
DOSE
CONTROL
SUCCESSIVE
TAKE-HOME
WEEKS
Fig 1. Total number of 10 mg diaxepam doses requested during successive experimental weeks by 8 individual methadone maintenance clients. Since two 10 mg diazepam doses were available daily, a maximum of 14 doses could be requested in a 7 day week. Data points are connected in each column for 6 week blocks of time during which program privileges were available or unavailable following diaxepam refusal at the clinic. Brackets at the top of columns designate portions of the experiment during which either methadone take-home medication or limited methadone dosage self-control were available contingent upon diazepam refusal. Contingent portions of the experiment were preceded and followed by baseline periods during which no clinic privileges were available and requests for diaxepam had no consequences.
249
250
MAXINEL. STITZER.GEORGEE. BIGELOWand IRA LIEBSON
Table 2. Supplementary drug use: results of twice-weekly urinalysis tests for drugs other than benzodiazepines
Client
Number of urinalysis tests
Percent of tests with any positive indicator
22 45 50 51 56 56 52 41
12.1 13.3 48.0 14.0 30.4 33.9 25.0 56.1
JB WC MC cw GT WB DW MJ
Percent of tests positive* Opiates
Stimulants
0.0
0.0
4.4 2.0 5.3 8.9 33.9 0.0 1.3
0.0 6.0 0.0 0.0 1.8 0.0 4.9
Sedatives and other drugs 12.1 11.1 42.0 8.8 23.2 0.0 25.0 51.2
*A urine sample could be positive for more than one drug class. Therefore, the cumulative percent of tests positive for individual drug classes may be larger than the percent of tests with any positive indicator for a given client.
populations we and others have observed as many as 40% of clients showing consistent benzodiazepine positive urinalysis results (Bigelow et al., 1976; Woody et al., 1975a, 1975b). Supplementary drug use in methadone clients may represent a prototype of abusive drug ingestion. Such drug self-administration is strongly maintained habitual behavior which is resistant to treatment interventions. The present study has shown that supplementary drug use of methadone maintenance clients can be influenced by clinic privileges which are available contingent upon reductions of drug use. Thus, the study has shown that clinic privileges can be used as a therapeutic intervention tool to promote desirable behavior change. Previous research has shown that both methadone take-home medication (Stitzer et al., 1977) and methadone dosage self-control (Stitzer et al., 1979) are desirable privileges which can serve as reinforcers for methadone maintenance clients under certain conditions. The present study reveals that these two privileges are not equally potent reinforcers. While the opportunity to receive a single methadone take-home medication resulted in dramatic and stable reductions in diazepam use at the clinic, the opportunity to control methadone dose for a single day was much less effective in influencing benzodiazepine use at the clinic. The potency of dosage self-control options as reinforcers may depend upon the magnitude of dose change which is available; in the present study the largest alteration available was + 20 mg from the stable dose. This magnitude of acute dose alteration may be barely detectable or undetectable to individuals stabilized on methadone (SGtzer & Bigelow, 1976; Stitzer et al., 1979). Larger magnitude
Table 3. Results of once-weekly urinalysis tests for betuodiazepines* Client JB WC MC CW GT
Baseline ++++++ ++++++’ / +++++ o+++++ ++++++ Baseline
WB DW MJ
++++++ ++++++ ++++++
Take-home contingency ++++++ +++++ ++++++ +++++o ++++++ Dose self-control contingency ++++++ -F+o+++ ++o+++
Baseline + ++++++ ++++++ o+++++ ++++++ Baseline oo++++ ++/+++ ++++++
during consecutive experimental weeks Dose self-control contingency ++++++ ++oo++
Baseline
++
++++++
++++o+
++++++
++++++
Take-home contingency ++++++ o+++++ ++++
Baseline ++++++ +++o
*Urinalysis result shown for each week is from urine samples collected on Monday of the following week. Monday urinalysis test reflects benzodiazepine drug use during the previous week. + = Benzodiazepine positives; 0 = Benzodiazepine negative; / = missing data.
Contingent
reduction
of benzodiazepines
251
dose alterations which are more detectable to patients would undoubtedly serve as more effective reinforcers for promoting behavior change. Potency of dosage self-control options may also depend on drug preferences of individual clients. The one client who reduced his diazepam requests in order to obtain dosage self-control (WB) was also the only client who used supplementary opiates to any significant extent. Generally, illicit drug use is an invisible behavior which occurs outside the treatment clinic and which can rarely, if ever, be diredtly observed or quantified. Offering diazepam prescriptions at the clinic provided a clear methodological advantage for conducting the present study in that it brought a portion of the drug use of these drug abusing clients under direct observation and experimental control. This allowed for a clear experimental analysis of the relative efficacy of the program privileges in altering supplementary drug use. Self-administration of drugs under controlled experimental conditions has been used extensively in inpatient hospital settings to study environmental and pharmacological determinants of the self-administration of ethanol (Bigelow et al., 1975a), sedatives (Bigelow et al., 1975b; Pickens et al., 1977) and narcotics (Jones & Prada, 1975; Meyer et al., 1976). There have been very few examples, however, of drug abuse research conducted in outpatient settings which have used drug self-administration techniques (Schuster et al., 1971). The present study therefore represents a methodological advance by showing that drug self-administration techniques can be adapted to outpatient clinic situations in order to study determinants of drug use. and to develop new treatment interventions. The findings of the present study have important treatment implications and suggest that privileges available at the methadone maintenance clinic can be used in a rational and effective way to promote positive therapeutic change in the drug taking behavior of drug abusing individuals. Methadone clinics frequently prescribe antianxiety and other psychoactive drugs to clients who complain of emotional disturbances. While this may be clinically appropriate from some perspectives, it may have the detrimental effect of fostering further drug dependence in clients already predisposed to such dependence. Offering incentives contingent upon refusal of prescribed psychoactive drugs could provide a therapeutic technique for weaning clients away from supplementary drug use while simultaneously giving the client practice in the behavior of declining available drugs. The use of program privileges as incentives for drug abstinence may also have applicability to promoting reductions in drug use outside the methadone clinic. Contingent incentive procedures would be appropriate for promoting drug abstinence in polydrug abusers such as those in the present study. Another appropriate group for such interventions might be clients undergoing detoxification who are at risk for relapse to illicit narcotic drugs. Further research is needed to determine whether these intervention techniques can influence drug use outside the clinic. REFERENCES Bigelow, G., Griffiths, R. & Liebson, I. Experimental models for the modification of human drug self-administration: Methodological developments in the study of ethanol self-administration by alcoholics. Federation Proceedings, 1975a, 34, 1785-1792. Bigelow, G., Griffiths, R. & Liebson, I. Experimental drug self-administration: Methodology and application to the study of sedative drugs. Pharmacological Reviews, 1975b, 27, 523531. Bigelow, G., Lawrence, C., Stitzer, M. & Wells, D. Behavioral treatments during outpatient methadone maintenance: A controlled evaluation. Paper presented before the American Psychological Association, Washington, DC, September, 1976. Bigelow, G., Stitzer, M., Lawrence, L., Krasnegor, N., D’Lugoff, B. & Hawthorne, J. Narcotics addiction treatment: Behavioral methods concurrent with methadone maintenance. Internarional Journal of the Addictions, 1979, in press. Boudin, H. M. Contingency contracting as a therapeutic tool in the deceleration of amphetamine use. Behauiw Therapy, 1972, 3, 604408. Boudin, H. M., Regan, E. J. & Ruiz, M. R. Contingency contracting with drug abusers in the natural environment: Treatment evaluation. Paper presented before the American Psychological Association, San Francisco, August, 1977. Brill, L. & Chambers,C. D. The rationale and design for a multi-modality approach to methadone therapy. In c. D. Chambers & i,. Brill-(EdS) Methadone: Experiences and Issues. New York: Behavioral Publications, 1973. A.& 4/3-D
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Dole, V. P. & Nyswander, M. E. A medical treatment for diacetylmorphine (heroin) addiction. Journal of the American Medical Association, 1965, 193, 80-84. Dole, V. P. & Nyswander, M. E. Methadone maintenance treatment. A ten year perspective. Journal of the Americun
Medicul
Association,
1976, 235, 2117-2119.
Dole, V. P., Nyswander, M. E. & Warner, A. Successful treatment of 750 criminals addicts. Journal of the American Medical Association, 1968, 206, 2708-27 I I. Eriksson, J. H., GGtestam, K. G., Melin, L. & est, L. G. A token economy treatment of drug addiction. Behaviour Research and Therapy, 1975, 13, 113-125. Gearing, F. R. Methadone maintenance treatment 5 years later-where are they now? American Journal of Public Health, Supplement, 1974. 64, 4450. Glicksman, M., Ottomanelli, G. & Cutler, R. The earn-your-way credit system: use of a token economy in narcotic rehabilitation. International Journal of the Addictions, 1971, 6, 525-531. Goldstein, A. Heroin addiction. Sequential treatment employing pharmacologic supports. Archives of Genera/ Psychiatry, 1976, 33, 353-358. Goldstein, A., Horns, W. H. & Hansteen, R. W. Is on-site urine testing of therapeutic value in a methadone maintenance treatment program? International Journal of the Addictions. 1977, 12, 717-728. Giitestam, K. G., Melin, L. & Ost, L. G. Behavioral techniques in the treatment of drug abuse: An evaluative review. Addictive Behaviors, 1975, 1, 205-225. Hall, S. M., Cooper, J. L., Burmaster. S. & Polk, A. Contingency contracting as a therapeutic tool with methadone maintenance clients: Six single subject studies. Behaviour Research and Therapy, 1977, 15. 438441. Jones. B. E. & Prada. J. A. Drug-seeking behavior during methadone maintenance. Psychopharmacologiu. 1975.41,
7-10.
Leitenberg H. (Ed) Hundbook qf Behuvior Modijcation and Behavior Therapy. Englewood Cliffs, NJ: PrenticeHall, 1976. Licbson. I.. Bigelow. G. & Flamer. R. Alcoholism among methadone patients: a specific treatment method. American Journal of Psychiatry. 1973, 130, 483485. Ling. W., Klett. J. & Gillis, R. D. A cooperative clinical study of methadyl acetate. Archives of Genera/ Psychiatry, 1978, 35, 345-353. Melin, L. & GGtestam, K. G. A contingency management program on a drug-free unit for intravenous amphetamine addicts. Journal of Behavior Therapy and Experimental Psychiatry, 1973, 4, 331-337. Melin, L., Andersson. B. E. & Ggtestam, K. G. Contingency management in a methadone maintenance treatment program. Addictive Behaviors, 1975. I, 151-158. Meyer, R. E., Mirin, S. M., Altman. J. L. & McNamee, H. B. A behavioral paradigm for the evaluation of narcotic antagonists. Archives of General Psychiatry, 1976. 33, 371-377. O’Brien. J. S., Raynes, A. E. & Patch, V. D. An operant reinforcement system to improve ward behavior in inpatient &ug addicts. Journal of Behavior Therapy and Experimental Psychi&y, 1971, 2, 239-242. Pickens, R., Cunningham, M. R., Heston, L. L., Eckert, E. & Gustafson, L. K. Dose preference during pentobarbital self-administration by humans. Journal of Pharmacology _. and Experimental Therapeutics, 1977, 203, 310-318. Schuster, C. R.. Smith, B. B. & Jaffe J. H. Drug abuse in heroin users. An experimental study of self-administration of methadone. codeine and pentazocine. Archives of General Psychiatry, 1971, 24, 359-362. Stitzer. M. & Bigelow. G. Stabilization on methadone: symptomatology and discriminability of methadone dose alterations. Proceedings of the Committee on Problems of Drug Dependence, pp. lOO3-1017, Washington, DC: National Academy of Science, 1976. Stitzer, M. & Bigelow, G. Contingency management in a methadone maintenance program: Availability of reinforcers. International Journal of the Addictions, 1978, 13, 737-746. Stitzer, M., Blgelow, G., Lawrence, C., Cohen, J.. D’Lugoff, B. & Hawthorne, J. Mechcatlon take-home as a reinforcer in a methadone maintenance program. Addictive Behaviors, 1977, 2, 9-14. Stitzer. M., Bigelow, G. & Liebson, I. Supplementary methadone self-administration among methadone maintenance clients. Addictive Behaviors, 1979, 4, 61-66. Woody, G. E., Mintz, J., O’Hare, K., O’Brien, C. P., Greenstein, R. A. & Hargrove, E. Diazepam use by patients in a methadone program-how serious a problem? Journal of Psychedelic Drugs, 1975a. 7. 373-379. Woody, G. E., O’Brien, C. P. & Greenstein, R. Misuse and abuse of diazepam: an increasingly common medical problem. International Journal of the Addictions, 1975b. 10, 843-848. Yen, S. Availability of activity reinforcers in a drug abuse clinic: a preliminary report. Psychological Reports, 1974. 34. 1021-1022.
0306.4603/79/0701-0245S02.00fil
REDUCING BENZODIAZEPINE SELF-ADMINISTRATION WITH CONTINGENT REINFORCEMENT* MAXINE L. STITZBR, GEORGE E. BIGEL~W and IRA LIEBSON Department of Psychiatry, Baltimore City Hospitals and Department of Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine Abstract-The purpose of the present study was to determine whether drug self-administration by methadone maintenance clients can be influenced by offering methadone clinic privileges contingent upon reductions in drug use, and to compare the reinforcing efficacy in this regard of two different clinic privileges. Eight methadone maintenance clients who had histories of supplemental benzodiazepine use participated. In order to transfer illicit drug use to the treatment clinic, clients were prescribed diazepam, 20mg/day, at the methadone clinic dispensary. Following assessment of baseline diazepam use, clients were offered, during 6-week blocks of time, either the chance to obtain a single methadone take-home dose or the chance to self-regulate their methadone dose for a single day. These privileges were contingent upon refusing prescribed diazepam at the clinic. During baseline weeks, 95.6% of available diazepam doses were requested. When take-home privileges were available, only 11.2% of diazepam doses were requested, while when dose self-control was available, 69.7% of doses were requested. The study showed that the supplemental drug use of methadone maintenance clients can be influenced by clinic privileges which are available contingent upon reductions of drug use. The medication take-home privilege was more effective as a reinforcer than was limited methadone dosage selfcontrol. Methadone clinic privileges can be used as intervention tools to promote desirable therapeutic behavior change in drug addicts, and in particular to promote reductions in supplemental drug use.
Methadone maintenance has been the treatment of choice for narcotics addiction for a number of years (Dole & Nyswander, 1965), and has demonstrated efficacy in reducing illicit heroin use and promoting improved social adjustment among addicts (Dole et al., 1968; Gearing, 1974). Nevertheless, many addicts have long-standing deficits in social and personal adjustment which do not abate after entry into methadone treatment. Furthermore, many addicts continue to abuse various drugs during their enrollment in methadone maintenance treatment. Thus, the need for ancillary treatment in addition to methadone is frequently emphasized (Brill & Chambers, 1973; Dole & Nyswander, 1976; Goldstein, 1976). Contingency management procedures including token economies and individualized contingency contracting have achieved widespread application in a variety of mental health fields and have been enormously .successful in promoting positive therapeutic outcomes (Leitenberg, 1976). In the area of drug abuse, however, these promising techniques have received relatively little attention and evaluation (GStestam et al., 1975). Several investigators have utilized contingency management programs with addicts who were living on inpatient wards. These programs increased participation in ward activities and promoted other socially acceptable behaviors (Eriksson et al., 1975; Glicksman et al., 1971; Melin & Gotestam, 1973; Melin ef al., 1975; O’Brien et al., 1971). Contingency management prodecures have also been applied in outpatient settings to promote improved social and personal adjustment (Bigelow ef al., 1979; Boudin et al., 1977; Hall et al., 1977). In addition, several investigators have described the use of contingency contracting or contingent incentive procedures specifically to promote reductions in use of drugs and alcohol among addict clients (Bigelow et al., 1976; Boudin, 1972; Hall et al., 1977; Liebson et al., 1973). Methadone maintenance clinics provide a potentially useful site for instituting vigorous contingency management intervention programs with addicts. Because methadone is a potent reinforcer which maintains addict clients in treatment, the methadone *This research was supported by USPHS Grant No. DA-01472 and Research Scientist Development Award No. DA-00050 from the National Institute on Drug Abuse. Send reprint requests to: Dr M. Stitzer, Baltimore City Hospitals, D-S-West, 4940 Eastern Avenue, Baltimore, MD 21224. U.S.A. 245
MANNEL. STITZER, GEORGE E. BIGELOW and IRA LIEBSON
246
clinic allows relatively long term contact with a drug abusing patient population. Furthermore, treatment clinic services and program privileges have potential value as reinforcers for use in contingent therapeutic arrangements (Hall et al., 1977; Stitzer & Bigelow, 1978; Yen, 1974). Methadone take-home medication (Bigelow et al., 1976; Stitzer et al., 1977) and limited methadone dosage self-control by clients (Stitzer et al., 1979) have both been identified as program privileges with potential value for promoting therapeutic change when used in contingent arrangements. Drug ingestion is ultimately the behaviour of central concern for drug abuse treatment. Furthermore, continued supplemental use of drugs by methadone maintenance clients is almost universally reported, the two drug classes which are notable for their continued use by a substantial portion of methadone maintenance clients being heroin (Bigelow et al., 1976; Goldstein et al., 1977; Ling et al., 1978; Woody et al., 1975a) and benzodiazepines (Bigelow et al., 1976; Woody et al., 1975a, 1975b). It would be of particular clinical relevence to assess the extent to which drug ingestion can be influenced by program privileges which are made available at the clinic in contingent arrangements. The purpose of the present study is to determine whether program privileges can be used to influence drug self-administration at the methadone clinic and to compare the reinforcing efficacy in this regard of two different program privileges which previous research suggests could act as reinforcers for methadone maintenance clients: methadone take-home medication and limited control over methadone dosage. METHODS Subjects
Eight clients enrolled in a methadone maintenance treatment research clinic participated. Table 1 shows demographic characteristics of the study participants. Clients tended to have poor personal and social adjustment: most were unemployed, had long histories of narcotics use and supplemented their methadone with a variety of drugs. All study participants had histories of supplementary benzodiazepine use as indicated by clinical interview, while current benzodiazepine use was verified by urinalysis tests. Setting
Experiments were conducted in an outpatient methadone maintenance research clinic with an enrollment of about 40 clients. Prior to enrolling in the research clinic, clients gave their informed consent to participate in studies in which they would be offered incentives whose delivery might depend upon their drug use or other behaviors. General clinic procedures
Clients reported to the methadone clinic 7 days a week and ingested methadone under nursing supervision. Urine samples were collected twice weekly (Monday and Table
1. Characteristics
Age
Race*
Years of education
JB WC MC cw GT WB DW MJ
19 30 28 26 23 39 30 21
W W W W W B W W
11 I1 II II II 8 12 12
Average
27.75
Client
*W = tunemp
10.9
Caucasian; B = Black. = unemployed; pt = part time; ft = full time
of study
participants
Years of continuous narcotics use 4 II I 5 9 13 13 10 9.
Employmentt during study unemp unemp unemp Pt unemp unemp unemp ft
Methadone dose (mg) 60 50 80 50 50 60 50 50 56.25
Contingent reduction of benzodiazepines
247
Friday). All samples were routinely analyzed for methadone, opiates (heroin, morphine, codeine, meperidine, and hydromorphone), quinine (which was considered in data analyses as evidence of opiate use), barbiturates (phenobarbital, unspecified barbiturates), nonbarbiturate sedatives (meprobamate, methaqualone, glutethimide, ethchlorvynol), stimulants (cocaine, amphetamine, methamphetamine, phenmetrazine) and phenothiazines, phenytoin and propoxyphene which are grouped in a single category called “other drugs” for purposes of data analysis. Study procedures
Each study participant received a prescription for diazepam, 20 mg/day from the clinic. The therapeutic rationale for prescribing diazepam was to shift illicit use of benzodiazepines by these clients to the treatment clinic. The experimental rationale was to bring a portion of the benzodiazepine use of these clients under direct experimental observation and control at the research clinic. If a client requested diazepam on a given day he was required to swallow one 10 mg tablet at the dispensary window under nursing supervision. He then received the second 10mg tablet to ingest later in the day as needed. Clients were free to request or decline diazepam daily throughout the study. Contingent and noncontingent periods, generally of 6-week duration, alternated throughout the study. During noncontingent or baseline weeks no consequences were attached to diazepam request. During contingent weeks, clients could receive program privileges by refusing diazepam at the clinic dispensary. The privileges offered were methadone take-home medication or limited methadone dosage self-regulation. The former consisted of the delivery to the client of a bottle containing his regular methadone dose to be ingested on the following day at the time of the usual clinic visit. The latter consisted of the opportunity to alter the stable methadone dose on a single day by as much as f 20 mg or + 50% of the stable dose, whichever was smaller. All study participants had been exposed to the dose self-regulation procedure during a previous experiment (Stitzer et al., 1979) and all had taken advantage of the self-regulation opportunity by increasing their dose. No study clients had received take-homes at this clinic except on occasional holidays when the clinic was closed, but all had been enrolled previously in other methadone programs and it is therefore likely that participants had been exposed to take-home privileges in the past. For 5 study participants take-home privileges were available for diazepam refusal during the first contingent period while dose self-control was available during the second contingent period. The remaining 3 clients were exposed to the 2 program privilege reinforcers in the reverse order. During contingent weeks a program privilege (take-home medication or dosage selfcontrol) could generally be obtained by refusing diazepam for 3 or 4 consecutive days. A maximum of 2 privileges could be obtained each week by refusing diazepam 7 consecutive days. Privileges earned by diazepam refusal were delivered one at a time after completion of the diazepam refusal requirements and could not be “saved up”. That is, each privilege had to be used before credit was given toward earning the next privilege. If a client requested diazepam at any time during contingent weeks of the study, 4 consecutive days of diazepam refusal were required to obtain the next privilege. During the first week of each contingent phase, a more dense schedule of reinforcer availability was in effect. Clients could obtain a maximum of three privileges by diazepam refusal during the first of the 6 contingent weeks. Since clients had the option of coming to the clinic to request diazepam even on days when they received a methadone take-home dose, these take home days were counted as a day of diazepam refusal toward the next available privilege. Instructions
to subjects
Study participants were told that during certain portions of the experiment they would be able to choose between taking diazepam at the clinic and receiving a different program privilege. The rules governing program privileges and how these could be obtained
248
MAXINE L. STITZER,GEORGEE. BIGEL~W and IRA LIEBSON
by diazepam refusal were explained in detail. Verbal and written instructions indicated that the diazepam prescription would be available throughout the experiment, that the decision to use the prescription was always’ up to the client and that the point of the study was to see what clients choose when offered the choice between diazepam and other program privileges. RESULTS
Figure 1 shows the number of 10 mg diazepam doses requested at the clinic dispensary during each week of the study by individual study participants. During all baseline weeks combined, 95.6% of available diazepam doses were requested. When the takehome reinforcement was available, virtually all clients refused diazepam regularly in order to receive these privileges. The only exceptions were MC who did not refuse diazepam until the third week of the take-home contingency period and GT whose diazepam refusal was variable throughout the contingent period. Overall only 11.2% of available diazepam doses were requested when refusal resulted in take-home privileges. In contrast, only one client (WB) refused diazepams consistently in order to obtain dose self-regulation opportunities. Typically, clients refused some or all diazepam doses in the first week of the methadone dose sell-control contingent period (CW, GT, DW, MJ) then returned to regular diazepam use. Overall, 69.7% of available diazepam doses were requested when refusal resulted in methadone dose self-control opportunities. Clients might continue benzodiazepine use outside the clinic even if they refused diazepam at the clinic dispensary. Benzodiazepine urinalysis results would reveal whether clients discontinued benzodiazepine use entirely or continued some use outside the clinic. Benzodiazepine urinalysis results are presented in Table 3. There were 9 instances where all diazepam doses were refused for 2 weeks or longer (one instance each for JB, WC, CW, DW, and MJ: 2 instances each for MC and WB). Since. it would take at least 2 weeks for benzodiazepines to clear from the body following abrupt cessation of their use, we could not expect to see clean urines before this amount of time. Only 3 of these instances of discontinued diazepam use at the clinic are correlated with any benzodiazepine free urinalysis tests (MC during methadone dosage self-control contingency, CW at the end of the take home contingency and WB following the end of the methadone dose self-control contingency). In general, then, urinalysis tests indicated that most clients may have engaged in some benzodiazepine use outside the clinic during periods of time when they were refusing diazepam at the clinic dispensary. However, the urinalysis test.gives no information about the frequency or ,quantity of use. In fact, ingestion of a single low dose of benzodiazepines might be detected in urine for up to 2 weeks. As shown in Table 2, study participants used supplemental drugs from multiple drug classes in addition to benzodiazepines. Although the observed level of drug use varied considerably across individuals, the pattern of use was similar in that all but one (WB) used a variety of sedative and miscellaneous drugs in addition to benzodiazepines and none of these clients used stimulants to any significant extent. Only client WB showed substantial amounts of opiate use. Analysis of all drug positive indicators obtained during the study for the entire group revealed that phenothiazine positives accounted for the largest single percentage of drug positive indicators (29.6% of positive indicators) with unspecified barbiturate the second most prevalent class (24.6% of positive indicators) and phenobarbital the third” most prevalent (13.6% of positive indicators). Phenothiazine positives are possibly due to the use of Phenergan (promethazine) a sedative with antihistaminic and antiemetic properties which is purported to “boost” the effects of methadone. An analysis of drug use over time revealed no noticeable trend in the frequency or type of drug use during contingent and noncontingent study periods or trends over the course of the entire study. DISCUSSiON
Supplementary drug use is a significant clinical problem among a portion of done maintenance clients. In reviewing urinalysis result of general methadone
metha-
clinic
Contingent reduction of benzodiazepines TAKE
‘4-
HOME
-1.
DOSE
CONTROL
:
DOSE
CONTROL
SUCCESSIVE
TAKE-HOME
WEEKS
Fig 1. Total number of 10 mg diaxepam doses requested during successive experimental weeks by 8 individual methadone maintenance clients. Since two 10 mg diazepam doses were available daily, a maximum of 14 doses could be requested in a 7 day week. Data points are connected in each column for 6 week blocks of time during which program privileges were available or unavailable following diaxepam refusal at the clinic. Brackets at the top of columns designate portions of the experiment during which either methadone take-home medication or limited methadone dosage self-control were available contingent upon diazepam refusal. Contingent portions of the experiment were preceded and followed by baseline periods during which no clinic privileges were available and requests for diaxepam had no consequences.
249
250
MAXINEL. STITZER.GEORGEE. BIGELOWand IRA LIEBSON
Table 2. Supplementary drug use: results of twice-weekly urinalysis tests for drugs other than benzodiazepines
Client
Number of urinalysis tests
Percent of tests with any positive indicator
22 45 50 51 56 56 52 41
12.1 13.3 48.0 14.0 30.4 33.9 25.0 56.1
JB WC MC cw GT WB DW MJ
Percent of tests positive* Opiates
Stimulants
0.0
0.0
4.4 2.0 5.3 8.9 33.9 0.0 1.3
0.0 6.0 0.0 0.0 1.8 0.0 4.9
Sedatives and other drugs 12.1 11.1 42.0 8.8 23.2 0.0 25.0 51.2
*A urine sample could be positive for more than one drug class. Therefore, the cumulative percent of tests positive for individual drug classes may be larger than the percent of tests with any positive indicator for a given client.
populations we and others have observed as many as 40% of clients showing consistent benzodiazepine positive urinalysis results (Bigelow et al., 1976; Woody et al., 1975a, 1975b). Supplementary drug use in methadone clients may represent a prototype of abusive drug ingestion. Such drug self-administration is strongly maintained habitual behavior which is resistant to treatment interventions. The present study has shown that supplementary drug use of methadone maintenance clients can be influenced by clinic privileges which are available contingent upon reductions of drug use. Thus, the study has shown that clinic privileges can be used as a therapeutic intervention tool to promote desirable behavior change. Previous research has shown that both methadone take-home medication (Stitzer et al., 1977) and methadone dosage self-control (Stitzer et al., 1979) are desirable privileges which can serve as reinforcers for methadone maintenance clients under certain conditions. The present study reveals that these two privileges are not equally potent reinforcers. While the opportunity to receive a single methadone take-home medication resulted in dramatic and stable reductions in diazepam use at the clinic, the opportunity to control methadone dose for a single day was much less effective in influencing benzodiazepine use at the clinic. The potency of dosage self-control options as reinforcers may depend upon the magnitude of dose change which is available; in the present study the largest alteration available was + 20 mg from the stable dose. This magnitude of acute dose alteration may be barely detectable or undetectable to individuals stabilized on methadone (SGtzer & Bigelow, 1976; Stitzer et al., 1979). Larger magnitude
Table 3. Results of once-weekly urinalysis tests for betuodiazepines* Client JB WC MC CW GT
Baseline ++++++ ++++++’ / +++++ o+++++ ++++++ Baseline
WB DW MJ
++++++ ++++++ ++++++
Take-home contingency ++++++ +++++ ++++++ +++++o ++++++ Dose self-control contingency ++++++ -F+o+++ ++o+++
Baseline + ++++++ ++++++ o+++++ ++++++ Baseline oo++++ ++/+++ ++++++
during consecutive experimental weeks Dose self-control contingency ++++++ ++oo++
Baseline
++
++++++
++++o+
++++++
++++++
Take-home contingency ++++++ o+++++ ++++
Baseline ++++++ +++o
*Urinalysis result shown for each week is from urine samples collected on Monday of the following week. Monday urinalysis test reflects benzodiazepine drug use during the previous week. + = Benzodiazepine positives; 0 = Benzodiazepine negative; / = missing data.
Contingent
reduction
of benzodiazepines
251
dose alterations which are more detectable to patients would undoubtedly serve as more effective reinforcers for promoting behavior change. Potency of dosage self-control options may also depend on drug preferences of individual clients. The one client who reduced his diazepam requests in order to obtain dosage self-control (WB) was also the only client who used supplementary opiates to any significant extent. Generally, illicit drug use is an invisible behavior which occurs outside the treatment clinic and which can rarely, if ever, be diredtly observed or quantified. Offering diazepam prescriptions at the clinic provided a clear methodological advantage for conducting the present study in that it brought a portion of the drug use of these drug abusing clients under direct observation and experimental control. This allowed for a clear experimental analysis of the relative efficacy of the program privileges in altering supplementary drug use. Self-administration of drugs under controlled experimental conditions has been used extensively in inpatient hospital settings to study environmental and pharmacological determinants of the self-administration of ethanol (Bigelow et al., 1975a), sedatives (Bigelow et al., 1975b; Pickens et al., 1977) and narcotics (Jones & Prada, 1975; Meyer et al., 1976). There have been very few examples, however, of drug abuse research conducted in outpatient settings which have used drug self-administration techniques (Schuster et al., 1971). The present study therefore represents a methodological advance by showing that drug self-administration techniques can be adapted to outpatient clinic situations in order to study determinants of drug use. and to develop new treatment interventions. The findings of the present study have important treatment implications and suggest that privileges available at the methadone maintenance clinic can be used in a rational and effective way to promote positive therapeutic change in the drug taking behavior of drug abusing individuals. Methadone clinics frequently prescribe antianxiety and other psychoactive drugs to clients who complain of emotional disturbances. While this may be clinically appropriate from some perspectives, it may have the detrimental effect of fostering further drug dependence in clients already predisposed to such dependence. Offering incentives contingent upon refusal of prescribed psychoactive drugs could provide a therapeutic technique for weaning clients away from supplementary drug use while simultaneously giving the client practice in the behavior of declining available drugs. The use of program privileges as incentives for drug abstinence may also have applicability to promoting reductions in drug use outside the methadone clinic. Contingent incentive procedures would be appropriate for promoting drug abstinence in polydrug abusers such as those in the present study. Another appropriate group for such interventions might be clients undergoing detoxification who are at risk for relapse to illicit narcotic drugs. Further research is needed to determine whether these intervention techniques can influence drug use outside the clinic. REFERENCES Bigelow, G., Griffiths, R. & Liebson, I. Experimental models for the modification of human drug self-administration: Methodological developments in the study of ethanol self-administration by alcoholics. Federation Proceedings, 1975a, 34, 1785-1792. Bigelow, G., Griffiths, R. & Liebson, I. Experimental drug self-administration: Methodology and application to the study of sedative drugs. Pharmacological Reviews, 1975b, 27, 523531. Bigelow, G., Lawrence, C., Stitzer, M. & Wells, D. Behavioral treatments during outpatient methadone maintenance: A controlled evaluation. Paper presented before the American Psychological Association, Washington, DC, September, 1976. Bigelow, G., Stitzer, M., Lawrence, L., Krasnegor, N., D’Lugoff, B. & Hawthorne, J. Narcotics addiction treatment: Behavioral methods concurrent with methadone maintenance. Internarional Journal of the Addictions, 1979, in press. Boudin, H. M. Contingency contracting as a therapeutic tool in the deceleration of amphetamine use. Behauiw Therapy, 1972, 3, 604408. Boudin, H. M., Regan, E. J. & Ruiz, M. R. Contingency contracting with drug abusers in the natural environment: Treatment evaluation. Paper presented before the American Psychological Association, San Francisco, August, 1977. Brill, L. & Chambers,C. D. The rationale and design for a multi-modality approach to methadone therapy. In c. D. Chambers & i,. Brill-(EdS) Methadone: Experiences and Issues. New York: Behavioral Publications, 1973. A.& 4/3-D
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