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A clinical trial using syrup of ipecac and activated charcoal concurrently
ORIGINAL CONTRIBUTION activated charcoal, syrup of ipecac, concurrent use; syrup of ipecac, activated charcoal, concurrent use
A Clinical Trial Using Syrup of Ipecac and Activated Charcoal Concurrently A prospective study was conducted to determine if the emetic effects of syrup of ipecac are preserved when activated charcoal is administered prior to emesis. Ten overdose patients who fulfilled the entrance criteria for the study were administered 60 mL syrup of ipecac by a nasogastric tube followed immediately by 500 mL of tap water. Ten minutes after the ipecac was administered, an aqueous slurry of 50 g activated charcoal diluted to 500 mL was instilled down the nasogastric tube and the tube was removed. Emetic response and time to emesis were recorded. Thirty minutes after emesis subsided, a second dose of 50 g activated charcoal (with sorbitoI) was administered orally. Emetic responses were noted in all ten patients. The patients averaged 3.7 emetic episodes. Emesis commenced in an average of I3.8 minutes from the start of ipecac administration and concluded in an average of 45.9 minutes. These results in patients are similar to those observed in a previously reported volunteer group similarly treated. This protocol allows early administration of activated charcoal while preserving the emetic properties of syrup of ipecac in the patients treated. [Freedman GE, Pastemak S, Krenzelok EP: A clinical trial using syrup of ipecac and activated charcoal concurrently. Ann Emerg Med February I987;16:164-166.]
Glenn E Freedman, MD*¢ Steve Pasternak, MD* Edward P Krenzelok, PharmD*:~ Pittsburgh, Pennsylvania
INTRODUCTION Routine treatment of the awake overdose patient begins with gastric emptying by syrup-of-ipecac-induced emesis, followed by activated charcoal (AC) administration after vomiting ends. This sequence typically involves a oneto-two-hour delay between the start of treatment and AC administration, due to the widely held belief that AC will neutralize the emetic properties of ipecac if administered concurrently, and that emesis of AC will occur if it is given too soon.I-a Scientific data to support these views are sparse. AC is most effective when it is administered early in treatment. 5 Delay in the administration of AC allows the host to continue to absorb the ingested substance and allows the substance to move distally down the gastrointestinal (GI) tract, preventing subsequent intragastric mixture and binding with AC. Recent studies have shown therapeutic equivalence and even superiority following early administration of AC when compared to routine treatment using gastric emptying followed by AC.S,6 The therapeutic contributions of ipecac and AC occur by different mechanisms. Ipecac-induced emesis attempts to remove intragastric residual. 4 AC adsorbs toxic substances within the GI tract, forming an AC toxin complex and thereby preventing host absorption of the toxin.7 To determine ff ipecac would produce emesis in the presence of activated charcoal, thus making it available as an early treatment intervention, we examined emesis rates in ten volunteers who received ipecac and pre-emetic AC. Contrary to conventional teaching, emesis was observed in 80% of the volunteers in an average of 20 minutes when an aqueous AC (50-g) slurry was administered five minutes after ipecac (60 mL).8 Based on these preliminary results, a clinical study was developed to examine a similar protocol in awake overdose patients being treated in an emergency department.
Address for reprints: Edward P Krenzelok, PharmD, Pittsburgh Poison Center, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania1'5213.
From the Pittsburgh Poison Center:~ and Affiliated Residency in Emergency Medicine,* University of Pittsburgh; and Emergency Department, Mercy Hospital,t Pittsburgh, Pennsylvania. Received for publication May 15, 1986. Revision received August 14, 1986. Accepted for publication September 8, 1986. Presented at the University for Emergency Medicine Annual Meeting in Portland, Oregon, May 1986.
METHODS This prospective, nonblinded clinical study was approved by the Research and Human Rights Committee. The study population consisted of patients 16:2February 1987
Annals of Emergency Medicine
164/43
IPECAC & ACTIVATED CHARCOAL Freedman, Pasternak & Krenzelok
presenting to the ED with the chief complaint of an ingested poison or drag overdose when gastric evacuation was indicated. O n l y awake patients over 16 years of age, weighing a minim u m of 50 kg, and with an intact gag reflex were included in the study. Patients with a history of a bleeding diathesis, Mallory-Weiss syndrome, or an absent gag reflex were excluded from participation. Additional exclusions were toxic exposures involving tricyclic antidepressants, methanol, ethylene glycol, and corrosive and petroleum distillate products that were contraindications to emesis. Patients who satisfied the entry criteria had a routine ED history and physical e x a m i n a t i o n . C o n s e n t for participation was implied by the patient's need for emergency treatment, signed consent for therapy, or psychiatric c o m m i t m e n t . Once the patient was accepted into the study, a threepage protocol document was attached to the patient's chart. Page 1 listed the study entrance criteria, page 2 detailed the specific instructions for treatment according to the protocol, and page 3 was used to record data. The data sheet contained adequate space to collect the following information: patient name, address, age, sex, race, and weight; the suspected ingested substance; the estimated time of the ingestion; ipecac and activated charcoal a d m i n i s t r a t i o n times; the v o l u m e of water administered; the time of onset and conclusion of emesis; physical character of the emesis; and the time at which the second dose of activated charcoal was administered. Nurses' comments and patient disposition were recorded. The treatment protocol consisted of inserting an 18-F nasogastric tube. Placement was confirmed by air insufflation and auscultation of the right upper quadrant of the patient's abdomen. Syrup of ipecac 60 mL was administered tO the patient through the nasogastric tube, and the time of administration was recorded. This was followed by 500 mL of tap water instilled through the tube. Ten minutes after administration of the ipecac, an aqueous slurry of 50 g (240 mL) AC (Actidose!Aqua, Paddock Laboratories, Inc, Minneapolis) was diluted with tap water to a total volume of 500 mL and was instilled through the tube, which then was removed. The time at which the first emesis occurred was recorded. If emesis oc44/165
TABLE 1. Summ~lry of results Emesis Success Rate: 100% (10/10) Average Emetic episodes
3.7
First emesis Last emesis
13.8 rain 459 rain
AC second dose
79.9 rain
curred during a d m i n i s t r a t i o n of the AC, instillation was discontinued until the episode of emesis ceased. If cmesis did not occur within 40 minutes, gastric lavage was to be performed. Thirty minutes after the conclusion ot cmesis, a slurry of 50 g AC containing 195 g sorbitol was administered orally or through a nasogastric tube if indicated clinically. RESULTS Ten patients met the study entrance criteria. All had e m e t i c responses; nine of the ten had more than two e p i s o d e s of e m e s i s . T h e a v e r a g e number of emetic episodes was 3.7, with a range of one to eight episodes. T h e average time to the o n s e t of emesis from ipecac a d m i n i s t r a t i o n was ~3.8 minutes, with a range of five to 37 minutes. Three patients had an emetic episode before AC administration~ all of these also had several emetic episodes after AC was administered. The average time to the final emetic episode was 45.9 m i n u t e s , w i t h a range of 12 to 80 minutes. Seven of the ten patie~ts received a second close of AC with sorhitol as a cathartic. The average interval between receiving the first and second doses of AC was 79.9 minutes, with a range of 52 to Ill minutes (Tables 1 and 2). DISCUSSION This protocol permits AC to be used approximately one hour earlier than is routine practice in the treatment of poisonings. It also demonstrates the error of medical d o g m a t h a t states that the concurrent use of ipecac and AC is contraindicated) -4 Our study demonstrates that when a temporal separation of ten minutes exists between the administration of ipecac and AC, AC does not inhibit the emetic properties of ipecac. Preserving the emetic property ot Annals of Emergency Medicine
Range 1-8 5-21 min 12-80 min 52-111 min
ipecac m a y be as important as early AC when used m this protocol. The therapeutic effects of emesis may be enhanced when it is produced in the presence of AC. AC adsorbs toxins mstant]y. 7 Part of the AC-toxin complex is eliminated from the host by emesis, and the remainder passes through the GI tract as a nonabsorbable complex. The emetic property of ipecac may be preserved due to the ten-minute period between ipecac and AC administration, and it is not known if this protocol would be effective with a shorter period between the two treatments. The high dose of ipecac (60 mL) also may contribute to the success of this protocol; c o n v e n t i o n a l a m o u n t s of ipecac (30 mL) might not be effective. Other possible explanations are that t h e A C - i p e c a c c o m p l e x is pharmacologically active or that the ACipecac complex exists in equilibrium with a free fraction of ipecac that is sufficient to produce emesis. Whatever the reasons, this protocol is clinically effective; AC can be given very early and the emetic property of ipecac can be preserved at the same time. This protocol thus offers the advantage of maintaining the separate m e c h a n i s m s of a c t i o n of AC and ipecac while pursuing the early use of AC a d v o c a t e d in the c u r r e n t literature. The 60 mL of ipecac administered in this protocol is double the conventional dose, but equal to the total dose administered to an adult nonresponder. This dose was chosen due to the expectation that AC might adsorb and neutralize the e m e t i c properties of ipecac. There is no evidence to suggest t h a t a d u l t s w h o r e c e i v e this amount of ipecac are subject to emetree-reduced cardiac toxicity or myopathy. A n o t h e r d e p a r t u r e f r o m conventional therapy involves the use of a nasogastric tube for the administra16:2 February 1987 1
TABLE 2. P a t i e n t d a t a
Patient
Date
Drug
No. Episodes Emesis
First Emesis (min)*
Final Emesis (min)*
21
25
62
6
36
77
--
52
1
5/4
Haldol ®
2+
2
5/31
Parnate ®
8
3
6/17
Dolobid ®
2+
11
AC 2nd Dose (min)*
4
6/19
Sominex ®
1
12
12
5
8/06
Dalmane®/Dolophine ®
2+
37
77
--
6
8/13
Aspirin/Ethyl alcohol (EtOH)
3
5
50
7
8/23
Lysol ®
3
12
38
8
8/23
Lysol ®
3
10
24
--
9
8/24
Nalfon®/EtOH
5
17
71
111
10
8/24
Tylenol®/EtOH
8
7
80
105
77 75 --
*Time since syrup of ipecac administration.
tion of ipecac, water, a n d AC. T h i s route of a d m i n i s t r a t i o n w a s c h o s e n i n the earlier v o l u n t e e r g r o u p t o m i n i mize t h e e f f e c t s of c o m p l i a n c e a n d palatability o n e m e s i s rates. However, the clinical u t i l i t y of t h i s r o u t e became evident, as it r e d u c e d t h e n e e d to negotiate t r e a t m e n t w i t h p a t i e n t s in an e m e r g e n c y s i t u a t i o n a n d saved nursing t i m e w i t h drug a n d w a t e r administration. CONCLUSION This p r o t o c o l r e p r e s e n t e d a departure f r o m t h e c o n v e n t i o n a l u s e of both s y r u p of i p e c a c a n d a c t i v a t e d charcoal. It p e r m i t t e d t h e e a r l y preemetic u s e of AC, t h e r e b y t a k i n g ad-
16:2February 1987
v a n t a g e of i t s a d s o r p t i v e p r o p e r t i e s a n d still a l l o w i n g e m e s i s of t h e t o x i n to occur. T h e n u m b e r of p a t i e n t s studied so far h a s b e e n small, b u t we believe t h e p r o t o c o l p r o b a b l y h a s signific a n t utility.
REFERENCES 1. Haddad LM: A general approach to the emergency management of poisoning, in Haddad LM, Winchester JF (eds): Clinical Management of Poisoning and Drug Overdose. Philadelphia, WB Saunders, 1983, p 4-I8. 2. Wanke LA: Prevention of absorption: Dilution, emesis, gastric lavage, adsorption, catharsis, in Bayer MJ, Rumack BH, Wanke LA (eds)i Toxicologic Emergencies. Bowie, Maryland, Robert J Brody, I984, p 37-51. 3. American Society of Hospital Pharmacists: Ipecac syrup, in American Hospital Formulary
Annals of Emergency Medicine
Service - - Drug Information 85. Bethesda, Maryland, ASHP, 1985, p I293-1294. 4. Meester WD: Emesis and lavage. Vet Hum Toxicol 1980;8:225-233. 5. Neuvonen PJ, Varteanen M, Tokola O: Comparison of activated charcoal and ipecac syrup in prevention of drug absorption. Eur J Clin Pharmacol 1983;24:557-562. 6. Kulig K, Bar-Or D, Cantrill SV, et al: Management of acutely poisoned patients without gastric e m p t y i n g . A n n Emerg Med 1985; 14:562-567. 7. Neuvonen PJ: Clinical pharmacokinetics of oral activated charcoal in acute intoxications. Clin Pharmacokinet 1982;7:465-489. 8. Krenzelok EP, Pasternak S, Freedman GE: Preserving the emetic effect of syrup of ipecac with concurrent activated charcoal administration: A preliminary study. Clin Toxicol 1986;24:159-166.
166/45
A Clinical Trial Using Syrup of Ipecac and Activated Charcoal Concurrently A prospective study was conducted to determine if the emetic effects of syrup of ipecac are preserved when activated charcoal is administered prior to emesis. Ten overdose patients who fulfilled the entrance criteria for the study were administered 60 mL syrup of ipecac by a nasogastric tube followed immediately by 500 mL of tap water. Ten minutes after the ipecac was administered, an aqueous slurry of 50 g activated charcoal diluted to 500 mL was instilled down the nasogastric tube and the tube was removed. Emetic response and time to emesis were recorded. Thirty minutes after emesis subsided, a second dose of 50 g activated charcoal (with sorbitoI) was administered orally. Emetic responses were noted in all ten patients. The patients averaged 3.7 emetic episodes. Emesis commenced in an average of I3.8 minutes from the start of ipecac administration and concluded in an average of 45.9 minutes. These results in patients are similar to those observed in a previously reported volunteer group similarly treated. This protocol allows early administration of activated charcoal while preserving the emetic properties of syrup of ipecac in the patients treated. [Freedman GE, Pastemak S, Krenzelok EP: A clinical trial using syrup of ipecac and activated charcoal concurrently. Ann Emerg Med February I987;16:164-166.]
Glenn E Freedman, MD*¢ Steve Pasternak, MD* Edward P Krenzelok, PharmD*:~ Pittsburgh, Pennsylvania
INTRODUCTION Routine treatment of the awake overdose patient begins with gastric emptying by syrup-of-ipecac-induced emesis, followed by activated charcoal (AC) administration after vomiting ends. This sequence typically involves a oneto-two-hour delay between the start of treatment and AC administration, due to the widely held belief that AC will neutralize the emetic properties of ipecac if administered concurrently, and that emesis of AC will occur if it is given too soon.I-a Scientific data to support these views are sparse. AC is most effective when it is administered early in treatment. 5 Delay in the administration of AC allows the host to continue to absorb the ingested substance and allows the substance to move distally down the gastrointestinal (GI) tract, preventing subsequent intragastric mixture and binding with AC. Recent studies have shown therapeutic equivalence and even superiority following early administration of AC when compared to routine treatment using gastric emptying followed by AC.S,6 The therapeutic contributions of ipecac and AC occur by different mechanisms. Ipecac-induced emesis attempts to remove intragastric residual. 4 AC adsorbs toxic substances within the GI tract, forming an AC toxin complex and thereby preventing host absorption of the toxin.7 To determine ff ipecac would produce emesis in the presence of activated charcoal, thus making it available as an early treatment intervention, we examined emesis rates in ten volunteers who received ipecac and pre-emetic AC. Contrary to conventional teaching, emesis was observed in 80% of the volunteers in an average of 20 minutes when an aqueous AC (50-g) slurry was administered five minutes after ipecac (60 mL).8 Based on these preliminary results, a clinical study was developed to examine a similar protocol in awake overdose patients being treated in an emergency department.
Address for reprints: Edward P Krenzelok, PharmD, Pittsburgh Poison Center, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania1'5213.
From the Pittsburgh Poison Center:~ and Affiliated Residency in Emergency Medicine,* University of Pittsburgh; and Emergency Department, Mercy Hospital,t Pittsburgh, Pennsylvania. Received for publication May 15, 1986. Revision received August 14, 1986. Accepted for publication September 8, 1986. Presented at the University for Emergency Medicine Annual Meeting in Portland, Oregon, May 1986.
METHODS This prospective, nonblinded clinical study was approved by the Research and Human Rights Committee. The study population consisted of patients 16:2February 1987
Annals of Emergency Medicine
164/43
IPECAC & ACTIVATED CHARCOAL Freedman, Pasternak & Krenzelok
presenting to the ED with the chief complaint of an ingested poison or drag overdose when gastric evacuation was indicated. O n l y awake patients over 16 years of age, weighing a minim u m of 50 kg, and with an intact gag reflex were included in the study. Patients with a history of a bleeding diathesis, Mallory-Weiss syndrome, or an absent gag reflex were excluded from participation. Additional exclusions were toxic exposures involving tricyclic antidepressants, methanol, ethylene glycol, and corrosive and petroleum distillate products that were contraindications to emesis. Patients who satisfied the entry criteria had a routine ED history and physical e x a m i n a t i o n . C o n s e n t for participation was implied by the patient's need for emergency treatment, signed consent for therapy, or psychiatric c o m m i t m e n t . Once the patient was accepted into the study, a threepage protocol document was attached to the patient's chart. Page 1 listed the study entrance criteria, page 2 detailed the specific instructions for treatment according to the protocol, and page 3 was used to record data. The data sheet contained adequate space to collect the following information: patient name, address, age, sex, race, and weight; the suspected ingested substance; the estimated time of the ingestion; ipecac and activated charcoal a d m i n i s t r a t i o n times; the v o l u m e of water administered; the time of onset and conclusion of emesis; physical character of the emesis; and the time at which the second dose of activated charcoal was administered. Nurses' comments and patient disposition were recorded. The treatment protocol consisted of inserting an 18-F nasogastric tube. Placement was confirmed by air insufflation and auscultation of the right upper quadrant of the patient's abdomen. Syrup of ipecac 60 mL was administered tO the patient through the nasogastric tube, and the time of administration was recorded. This was followed by 500 mL of tap water instilled through the tube. Ten minutes after administration of the ipecac, an aqueous slurry of 50 g (240 mL) AC (Actidose!Aqua, Paddock Laboratories, Inc, Minneapolis) was diluted with tap water to a total volume of 500 mL and was instilled through the tube, which then was removed. The time at which the first emesis occurred was recorded. If emesis oc44/165
TABLE 1. Summ~lry of results Emesis Success Rate: 100% (10/10) Average Emetic episodes
3.7
First emesis Last emesis
13.8 rain 459 rain
AC second dose
79.9 rain
curred during a d m i n i s t r a t i o n of the AC, instillation was discontinued until the episode of emesis ceased. If cmesis did not occur within 40 minutes, gastric lavage was to be performed. Thirty minutes after the conclusion ot cmesis, a slurry of 50 g AC containing 195 g sorbitol was administered orally or through a nasogastric tube if indicated clinically. RESULTS Ten patients met the study entrance criteria. All had e m e t i c responses; nine of the ten had more than two e p i s o d e s of e m e s i s . T h e a v e r a g e number of emetic episodes was 3.7, with a range of one to eight episodes. T h e average time to the o n s e t of emesis from ipecac a d m i n i s t r a t i o n was ~3.8 minutes, with a range of five to 37 minutes. Three patients had an emetic episode before AC administration~ all of these also had several emetic episodes after AC was administered. The average time to the final emetic episode was 45.9 m i n u t e s , w i t h a range of 12 to 80 minutes. Seven of the ten patie~ts received a second close of AC with sorhitol as a cathartic. The average interval between receiving the first and second doses of AC was 79.9 minutes, with a range of 52 to Ill minutes (Tables 1 and 2). DISCUSSION This protocol permits AC to be used approximately one hour earlier than is routine practice in the treatment of poisonings. It also demonstrates the error of medical d o g m a t h a t states that the concurrent use of ipecac and AC is contraindicated) -4 Our study demonstrates that when a temporal separation of ten minutes exists between the administration of ipecac and AC, AC does not inhibit the emetic properties of ipecac. Preserving the emetic property ot Annals of Emergency Medicine
Range 1-8 5-21 min 12-80 min 52-111 min
ipecac m a y be as important as early AC when used m this protocol. The therapeutic effects of emesis may be enhanced when it is produced in the presence of AC. AC adsorbs toxins mstant]y. 7 Part of the AC-toxin complex is eliminated from the host by emesis, and the remainder passes through the GI tract as a nonabsorbable complex. The emetic property of ipecac may be preserved due to the ten-minute period between ipecac and AC administration, and it is not known if this protocol would be effective with a shorter period between the two treatments. The high dose of ipecac (60 mL) also may contribute to the success of this protocol; c o n v e n t i o n a l a m o u n t s of ipecac (30 mL) might not be effective. Other possible explanations are that t h e A C - i p e c a c c o m p l e x is pharmacologically active or that the ACipecac complex exists in equilibrium with a free fraction of ipecac that is sufficient to produce emesis. Whatever the reasons, this protocol is clinically effective; AC can be given very early and the emetic property of ipecac can be preserved at the same time. This protocol thus offers the advantage of maintaining the separate m e c h a n i s m s of a c t i o n of AC and ipecac while pursuing the early use of AC a d v o c a t e d in the c u r r e n t literature. The 60 mL of ipecac administered in this protocol is double the conventional dose, but equal to the total dose administered to an adult nonresponder. This dose was chosen due to the expectation that AC might adsorb and neutralize the e m e t i c properties of ipecac. There is no evidence to suggest t h a t a d u l t s w h o r e c e i v e this amount of ipecac are subject to emetree-reduced cardiac toxicity or myopathy. A n o t h e r d e p a r t u r e f r o m conventional therapy involves the use of a nasogastric tube for the administra16:2 February 1987 1
TABLE 2. P a t i e n t d a t a
Patient
Date
Drug
No. Episodes Emesis
First Emesis (min)*
Final Emesis (min)*
21
25
62
6
36
77
--
52
1
5/4
Haldol ®
2+
2
5/31
Parnate ®
8
3
6/17
Dolobid ®
2+
11
AC 2nd Dose (min)*
4
6/19
Sominex ®
1
12
12
5
8/06
Dalmane®/Dolophine ®
2+
37
77
--
6
8/13
Aspirin/Ethyl alcohol (EtOH)
3
5
50
7
8/23
Lysol ®
3
12
38
8
8/23
Lysol ®
3
10
24
--
9
8/24
Nalfon®/EtOH
5
17
71
111
10
8/24
Tylenol®/EtOH
8
7
80
105
77 75 --
*Time since syrup of ipecac administration.
tion of ipecac, water, a n d AC. T h i s route of a d m i n i s t r a t i o n w a s c h o s e n i n the earlier v o l u n t e e r g r o u p t o m i n i mize t h e e f f e c t s of c o m p l i a n c e a n d palatability o n e m e s i s rates. However, the clinical u t i l i t y of t h i s r o u t e became evident, as it r e d u c e d t h e n e e d to negotiate t r e a t m e n t w i t h p a t i e n t s in an e m e r g e n c y s i t u a t i o n a n d saved nursing t i m e w i t h drug a n d w a t e r administration. CONCLUSION This p r o t o c o l r e p r e s e n t e d a departure f r o m t h e c o n v e n t i o n a l u s e of both s y r u p of i p e c a c a n d a c t i v a t e d charcoal. It p e r m i t t e d t h e e a r l y preemetic u s e of AC, t h e r e b y t a k i n g ad-
16:2February 1987
v a n t a g e of i t s a d s o r p t i v e p r o p e r t i e s a n d still a l l o w i n g e m e s i s of t h e t o x i n to occur. T h e n u m b e r of p a t i e n t s studied so far h a s b e e n small, b u t we believe t h e p r o t o c o l p r o b a b l y h a s signific a n t utility.
REFERENCES 1. Haddad LM: A general approach to the emergency management of poisoning, in Haddad LM, Winchester JF (eds): Clinical Management of Poisoning and Drug Overdose. Philadelphia, WB Saunders, 1983, p 4-I8. 2. Wanke LA: Prevention of absorption: Dilution, emesis, gastric lavage, adsorption, catharsis, in Bayer MJ, Rumack BH, Wanke LA (eds)i Toxicologic Emergencies. Bowie, Maryland, Robert J Brody, I984, p 37-51. 3. American Society of Hospital Pharmacists: Ipecac syrup, in American Hospital Formulary
Annals of Emergency Medicine
Service - - Drug Information 85. Bethesda, Maryland, ASHP, 1985, p I293-1294. 4. Meester WD: Emesis and lavage. Vet Hum Toxicol 1980;8:225-233. 5. Neuvonen PJ, Varteanen M, Tokola O: Comparison of activated charcoal and ipecac syrup in prevention of drug absorption. Eur J Clin Pharmacol 1983;24:557-562. 6. Kulig K, Bar-Or D, Cantrill SV, et al: Management of acutely poisoned patients without gastric e m p t y i n g . A n n Emerg Med 1985; 14:562-567. 7. Neuvonen PJ: Clinical pharmacokinetics of oral activated charcoal in acute intoxications. Clin Pharmacokinet 1982;7:465-489. 8. Krenzelok EP, Pasternak S, Freedman GE: Preserving the emetic effect of syrup of ipecac with concurrent activated charcoal administration: A preliminary study. Clin Toxicol 1986;24:159-166.
166/45