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.

CONTRAINDICATED: Ethanol consumption with acitretin leads to the formation of etretinate, which has a much longer half-life than acitretin. Major human fetal abnormalities have been associated with the administration of acitretin, etretinate, and other retinoids. The longer elimination half-life of etretinate relative to acitretin increases the duration of teratogenic potential for female patients. In one case report of a patient with apparent sporadic ethanol intake, etretinate was present in plasma and fat for 52 months after acitretin was discontinued.

MANAGEMENT: Female patients should be warned that ethanol is contraindicated during active treatment with acitretin and for two months after cessation of 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.