Drug Interaction Report

GENERALLY AVOID: Theoretically, use of sodium picosulfate during or following antibiotic treatment may result in a reduced laxative effect of sodium picosulfate. The proposed mechanism involves antibiotic-induced reduction of colonic bacteria that hydrolyze sodium picosulfate, a prodrug, to its active metabolite bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM), a compound that stimulates colonic peristalsis. The clinical significance of this effect remains unknown.

MANAGEMENT: Consider use of an alternate laxative in patients who have recently taken or are currently taking an antibiotic. If concomitant use is required, additional bowel cleansing and colonoscopy may be required.

GENERALLY AVOID: Theoretically, use of sodium picosulfate during or following antibiotic treatment may result in a reduced laxative effect of sodium picosulfate. The proposed mechanism involves antibiotic-induced reduction of colonic bacteria that hydrolyze sodium picosulfate, a prodrug, to its active metabolite bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM), a compound that stimulates colonic peristalsis. The clinical significance of this effect remains unknown.

MANAGEMENT: Consider use of an alternate laxative in patients who have recently taken or are currently taking an antibiotic. If concomitant use is required, additional bowel cleansing and colonoscopy may be required.

ADJUST DOSING INTERVAL: Bowel cleansing products can increase the gastrointestinal transit rate. Oral medications administered within one hour of the start of administration of the bowel cleansing solution may be flushed from the gastrointestinal tract and not properly absorbed.

MANAGEMENT: Patients should be advised that absorption of oral medications may be impaired during bowel cleansing treatment. Oral medications (e.g., anticonvulsants, oral contraceptives, antidiabetic agents, antibiotics) should not be administered during and within one hour of starting bowel cleansing treatment whenever possible. However, if concomitant use cannot be avoided, monitoring for reduced therapeutic effects may be advisable.

MONITOR: Two cases have been reported in which patients on sulfamethoxazole-trimethoprim therapy, after consuming beer, reported flushing, heart palpitations, dyspnea, headache, and nausea (disulfiram - alcohol type reactions). First-generation sulfonylureas have been reported to cause facial flushing when administered with alcohol by inhibiting acetaldehyde dehydrogenase and subsequently causing acetaldehyde accumulation. Since sulfamethoxazole is chemically related to first-generation sulfonylureas, a disulfiram-like reaction with products containing sulfamethoxazole is theoretically possible. However, pharmacokinetic/pharmacodynamic data are lacking and in addition, the two reported cases cannot be clearly attributed to the concomitant use of sulfamethoxazole-trimethoprim and alcohol.

MANAGEMENT: Patients should be alerted to the potential for this interaction and although the risk for this interaction is minimal, caution is recommended while taking sulfamethoxazole-trimethoprim concomitantly with alcohol.