Drug Interaction Report

MONITOR: Coadministration of 5-aminosalicylate with other nephrotoxic agents may increase the risk and severity of renal impairment due to additive effects on the kidney. The use of 5-aminosalicylate or its prodrugs has been associated with rare reports of renal impairment including minimal change nephropathy, acute and chronic interstitial nephritis, and renal failure. Animal studies have also shown the kidney to be the major target organ of 5-aminosalicylate toxicity. Renal lesions including granular and hyaline casts, tubular degeneration, tubular dilation, renal infarct, papillary edema, papillary necrosis, tubular necrosis, interstitial fibrosis, and interstitial nephritis have been observed with large doses.

MANAGEMENT: Caution is advised when 5-aminosalicylate preparations are prescribed to patients who have recently received or are receiving treatment with other potentially nephrotoxic agents (e.g., aminoglycosides; polypeptide, glycopeptide, and polymyxin antibiotics; amphotericin B; adefovir; cidofovir; foscarnet; cisplatin; deferasirox; gallium nitrate; lithium; certain immunosuppressants; intravenous bisphosphonates; intravenous pentamidine; high intravenous dosages of methotrexate; high dosages and/or chronic use of nonsteroidal anti-inflammatory agents). Renal function should be evaluated prior to and during 5-aminosalicylate therapy.

GENERALLY AVOID: The concurrent use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) and ethanol may lead to gastrointestinal (GI) blood loss. The mechanism may be due to a combined local effect as well as inhibition of prostaglandins leading to decreased integrity of the GI lining.

MANAGEMENT: Patients should be counseled on this potential interaction and advised to refrain from alcohol consumption while taking aspirin or NSAIDs.

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.