Drug Interaction Report

GENERALLY AVOID: Concomitant use of cocaine with sympathomimetic agents such as epinephrine and phenylephrine may lead to additive cardiovascular effects. The proposed mechanism involves increased circulating catecholamines and increased activity of the sympathetic nervous system. Locally administered cocaine and epinephrine have been used in combination during septal surgery; however, concerns regarding cardiovascular side effects have been raised. Myocardial ischemia, myocardial infarction, and ventricular arrhythmias have been reported following coadministration of topical intranasal cocaine with epinephrine and phenylephrine during nasal and sinus surgery. Cases documenting the development of arrhythmias after the nasal application of cocaine and epinephrine 25%-0.18% topical paste have also been reported in 2 children and one adult receiving general anesthesia. However, the dosage of cocaine administered in these cases was above the maximum recommended dose in fit adults (1.5 mg/kg).

MANAGEMENT: Concomitant use of cocaine with sympathomimetic agents should be avoided. If coadministration is required, prolonged vital sign and ECG monitoring may be necessary.

GENERALLY AVOID: Use of anticholinergic agents with alcohol may result in sufficient impairment of attention so as to render driving and operating machinery more hazardous. In addition, the potential for abuse may be increased with the combination. The mechanism of interaction is not established but may involve additive depressant effects on the central nervous system. No effect of oral propantheline or atropine on blood alcohol levels was observed in healthy volunteers when administered before ingestion of a standard ethanol load. However, one study found impairment of attention in subjects given atropine 0.5 mg or glycopyrrolate 1 mg in combination with alcohol.

MANAGEMENT: Alcohol should generally be avoided during therapy with anticholinergic agents. Patients should be counseled to avoid activities requiring mental alertness until they know how these agents affect them.