Transdermal nitroglycerin ointment and patches

Transdermal Nitroglycerin Ointment and Patches layer. They can remain in place during swimming and showering, and Transdermal nitroglycerin prepara- need not be reapplied afterward. tions act similarly to the other niThere are also disadvantages with t r a t e s - t h e y dilate peripheral blood these new products. They are diffivessels to decrease the heart's work- cult to manipulate; some brands of load and oxygen consumption. The the patches are virtually impossible ointment and patches are used to for anyone with hand tremors or prevent and control angina but not moderate arthritis to open. People for acute episodes. may find the ointments too messy to Transdermalformulations of any handle. drug theoretically produce more Perhaps most important,transderconsistent drug blood levels, with less real nitroglycerins, especially the frequent side effects than oral prod- patches, are considerably more exucts. In addition, many patients ap- pensive than the older nitrates like preciate having fewer pills to swal- isosorbide dinitrate (Isordil, Sorbilow. trate) or pentaerythritoltetranitrate There are several advantages of (Peritrate). This last point undertransdermal nitroglycerin over this scores the importanceof not switchparticulardrug's oral dosage forms. ing to a new dosage form when a less Nitroglycerin ointment and patches expensive therapy achieves success are longer acting, becausethey avoid without adverse effects. These new the extensive first-pass metabolism productsare not "better"if angina is that oral nitrates undergo.* already under Control and the paTransdermal nitroglycerin begins tient doesn't find pill-takinginconveto exert its effects within 30 minutes. nient. This onset of action is similar to that Appfication of the oral nitrates. But while oral forms of nitroglycerin may act for Apply nitroglycerinointment and two to six hours, the action of nitro- patches to skin that is clean and dry. glycerin ointment lasts four to eight Remove the previous patch or residhours, and the patches continue to ual ointment before applying the work for 24 hours. Less frequent new dose. Avoid scars, calluses, skin doses therefore are possible. This folds, bruises, cuts, and irritatedarlonger angina control can be espe- eas on the skin. cially helpful during sleeping hours. Transdermalnitroglycerincan be The patches have the additional applied to almost any part of the advantage of a waterproof outer body except the distal extremities. Rotatingsites helps preventskin irritation. Caution the patient to observe for varied effects, such as any *After any oral drugis absorbed from the increase or decrease in anginal epismall intestine, it is immediately carried in the blood stream to the liver, heart, lungs, sodes, when different sites are used. and again through the heart before reachApplication over an obese area, for ing the general circulation. Nitroglycerin is example, may result in a decreased one of the many oral drugs that is rapidly therapeuticeffect as comparedto arand extensively metabolized on this "first pass" through the liver, reducing the total eas with less subcutaneousfat. bioavailable dose. Intravenous, sublingual, Measure the ointment carefully and transdermal nitroglycerin avoid this onto its applicator paper. Spread it first-pass effect, leaving the greater part of evenly over an area of skin at least each dose available to exert its pharmacological action. two by three inches, without rubbing BETSY TODD

152 GeriatricNursing May/June 1986

or massaging. Do not cut or trim patches in an attempt to modify the dose. Hairless skin allows optimal adherence and absorption. However, shaving body hair for this purpose is not recommended, as this will tend to cause skin irritationand may adversely affect the person's body image. Occlusive dressings (plastic wrap) will increase drug absorption, and are applied only if specifically ordered. These can increase the therapeutic effect of a dose that is not quite effective. Conversely, discontinuing occlusive dressings that have been used over transdermalnitroglycerin may decrease the intensity of unpleasantside effects.

Dose and Adverse Effects Doses of the ointmentand the various nitroglycerin patches may be expressed as inches, milligrams, or square millimeters.There have been no direct comparisons of the different products, so different brands should not be interchanged. Some patients may need to wear two ointment applicator papers, or multiple patch units, to obtain a good therapeutic effect. As with the oral nitrates, headaches are the most frequentand discomforting side effect. Some physicians recommend using the onset of headaches as a dosage guide, that is, increase the dose gradually until headache occurs, then cut back to the highest dose that does not cause headache. Headaches during initial therapy should subside within two or three weeks. If they continue, the patient

Betsy Todd, RN, BS, is a part-time staff nurse at Phelps Memorial Hospital Center, North Tarrytown, NY, and a lecturer/consultant on drug use among older adults.

Haldon

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DRUC~ AND THE ELDERLY

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INDICATIONSANDUSAGE:HALCIONTablets are indicated in the short-term man-

agementof insomniacharacterizedby difficulty in falling asleep,frequentnocturnal awakenings,and/or early morningawakenings. It is recommendedthat HALCIONnot be prescribedin quantities exceedinga one-menthsu~ly. CONTRAINDICATIONS: Patientswith known hypersensitivityto this drugor other bonzodiazeoines. HALCIONIs cor~traindioatedin pregnantwomendue to potential fetal damage. Patientslikely to becomepregnantwhile receivingHALCIONshouldbe warnedof the potentialrisk to the fetus. WARNINGS:Overdesaoemay occur at four times the maximumrecommendedtherapeutic dose.Patientsshouldbe cautionednot to exc,eedprescribeddosage... Becauseof its depressantCNS effects, patients snouldbe cautionedagainst engaoingin hazardousoccupationsrequiringcompletementalalertnessand also aboutthe simultaneousIngestionof alcohol and other CNS depressantdrugs. AntemgredeamnesiaandparadoxicalreactionshavebeenreportedwithHALCION someethel"benzooiazepmes. PRECAUTIONS:General:In elderlyand/or debilitatedpatients,treatmentshouldbe initiated at 0.125 mg to decreasethe POssibilityof developmentof oversedation, dizziness.orimpairedcoordination.Cautionshouldbe exercisedin patientswith signs or symptomsof depressionwhich could be intensified by hypnoticdrugs.Suicidal tendenciesand intentionaloverdosageis morecommonin these patients.Theusual precautionsshould be observedin patientswith impairedrenalor hepatic function and chronicpulmonaryinsufficiency.Informationfor Patients:Alert patients about: (a) consumptionof alcohol and drugs (b) possible fetal abnormalities,(c)operating machineryor driving (d) net increasing,prescribeddosa.~, (e) pos.s,ible worseningof sleep after discontinuingHALCION.L-acoratory/ests:Not ordinarilyrequiredin otherwise healthypatients. DrugInteractions:AdditiveCNS depressantenects with other psychotropics,anticonvulsants,antihistaminics,ethanol,and other CNS depressants. Pharmacokineticinteractionsof benzediazepineswith other drugshavebeenreported. Carcinogenesis,Mutaoenesis,Impairmentof Fertility: No evidenceof carcinogenic pot~ti_al.wasobservedin mice doting a 24.:month,stud)/with HALCIONin .dosesup. to 4006 times the humandose.~egnancy: eenzcoiazegmesmaycauseferal Damageir administeredduringpregnancy.Thechildbern of a motherwho is on benzodiazepines may be at somerisk lor withdrawalsymptomsand neonatalflaccidity duringthe postnatalperiod.Nursing Mothers:Administrationto nursingmothersis not recommended.PediatricUso: Safetyand efficacy in childrenbelowthe age of 18 havenot been established. ADVERSEREACTIONS:Duringplaceho-controlledclinical studies in which 1003 patientsreceivedHALCIONTablets,the most troublesomeside effects wereextensions of the pharmacologicactivity of HALCION,e.g.drowsiness,dizziness,or lightheadedness. HALCION Placebo 1003 997 Numberof Patients %enofPatientsReporting: tral Negus System 14,0 6.4 Drowsiness 9.7 8.4 Headache 7.8 3.1 Dizziness 5.2 4.5 Nervousness 4.9 0.9 Lightheadedness 4.6 0.8 CoordinationDisorder/Ataxia Gastrointestinal Nausea/Vomiting 4.6 3.7 In addition the followingadverseeventshavebeenreportedless frequently(i.e., 0.9-0.5%): euphoria,tachycardia,tiredness,confusionalstates/memoryimpairment, cramps/pain,depression visual disturbances. . . . . NamILe.,less than 0.5%) aeversereactions inc uoeoconst pat on,zastea terations diarrhea dry mouth,dermatitis/allergy,dreaming/nightmares,insomnia, paresthesia,tinnitus, dysesthesia,weakness,congestion,deathfrom hepatic failure m a patientalso receiwngdiuretic drugs. The followingadverseeventshavebeenreportedin associationwith the use of Ioenzodiazepines:dystonia,irritability,anorexia,fatigue,sedation,slurred speech, jaundice,pruritus, Oysarthria,changesin libido,menstrualirregularities,incontinence and urinaryretention. As with all benzodiazegines,paradoxicalreactionssuch as stimulation,agitation, increasedmuscle spasticity,sleep disturbances,hallucinationsand other adverse behavioraleffects may occur rarelyand in a randomfashion.Shouldthese occur, use of the drugshould be discontinued. No laboratorychangeswereconsideredto be of physiologicalsignificance. Whentreatmentis protracted,periodicbloodcounts,urinalysisand bloodchemistry analysesare advisable. Minor changesin EEGpatterns usuallyIow-voltagafast activity havebeenobserved in patientsduring HALCIONtherapyand are of no knownsignificance. DRUGABUSEAND DEPENDENCE:ControlledSubstance:HALClONTabletsare a ControlledSubstancein ScheduleIV.Abuse and Dependence:Withdrawalsymptoms haveoccurredfollowing abruptdiscontinuanceof benzodiazepines.Patientswith a histo~' of seizuresare at particularrisk. Addiction-pronepatients should be closely monitored.Repeatprescriptionsshouldbe limited to those undermedicalsupervision. OVERDOSAGE:Becauseof the potencyof triazolam,overdosagemay occur at 2 rag, four times the maximumrecommendedtherapeuticdose (0,5 mg).Manifestationsof overdesageinclude somnolence,confusion,impairedcoordination,slurredspeech, and ultimately,coma.Respiration,pulse, and blood pressureshould be monitoredand supportedby generalmeasureswhen necessary.Immediategastric lavageshould be performed.Multiple agentsmay havebeeningested. Storeat controlledroomtemperature150-30bOO C (590-860 F). Caution:Federallaw prohibitsdispensingwithout prescription. Reference: B-2-s 1. ConsensusConference:Drugs and insomnia:The use of medicationsto promote sleep.JAMA 1984;251:2410-2414. THEUPJOHNCOMPANY r,,~,~ 19~

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Kalamazoo,Michigan49001 USA

154 Geriatric Nursing May/June 1986

J-5859

can try to control this side effect by applying the nitroglycerin at new sites. If this doesn't work, a dosage reduction should be tried. If headaches persist despite site rotation, lowered doses, or both, transdermal nitroglycerin probablyshould be discontinued. Many practitioners cling to the idea that constant headaches indicate that the drug is working. However, few patients would agree that the decreasein day-to-dayquality of life is a reasonable trade-off for the drug's potential therapeutic effectiveness. Orthostatichypotensionand dizziness can also occur, and may be aggravated by alcohol consumption, hot weather, or long periods of standing. Flushing of the head and neck, nausea, vomiting, tachycardia, restlessness, and skin irritation are also possible. The symptoms of nitroglycerin overdose include cyanosis of the lips, nailbeds, and palms; extreme dizziness or fainting; extreme headache; shortness of breath; extreme tiredness or weakness; weak and unusually fast heartbeat; fever; and convulsions. Because nitroglycerinis metabolized rapidly,drug withdrawal and supportive care (bed rest, blood pressure monitoring, blood pressuremaintenancedrugs if necessary) usually alleviate the symptoms within a short time. If nitroglycerintherapy is discontinued, a gradual dosage reduction over four to six weeks is recommended to prevent rebound attacks of angina. Store transdermal nitroglycerin away from heat and light, with the individualpatches unopenedand the ointment capped. Keep these products away from children and pets. Nurses or others administeringthese drugs should remember to wash their hands thoroughlyafter preparing the dose. Whether the older nitrates or the new transdermal forms are used, nondrug measures of angina control--weight loss, cessation of smoking, and a common sense programof regular exercise---deserve continued emphasis.