There is no specific antidote for overdose of LOTRONEX (alosetron hydrochloride) . Patients should be managed with appropriate supportive therapy. Individual oral doses as large as 16 mg have been administered in clinical studies without significant adverse events. This dose is 8 times higher than the recommended total daily dose. Inhibition of the metabolic elimination and reduced first pass of other drugs might occur with overdoses of alosetron (see PRECAUTIONS: DRUG INTERACTIONS). Single oral doses of LOTRONEX (alosetron hydrochloride) at 15 mg/kg in female mice and 60 mg/kg in female rats (30 and 240 times, respectively, the recommended human dose based on body surface area) were lethal. Symptoms of acute toxicity were labored respiration, subdued behavior, ataxia, tremors, and convulsions.

LOTRONEX (alosetron hydrochloride) should not be initiated in patients with constipation (see WARNINGS).

LOTRONEX (alosetron hydrochloride) is contraindicated in patients with a history of the following:

• chronic or severe constipation or sequelae from constipation
• intestinal obstruction, stricture, toxic megacolon, gastrointestinal perforation, and/or adhesions
• ischemic colitis, impaired intestinal circulation, thrombophlebitis, or hypercoagulable state
• Crohn's disease or ulcerative colitis
• diverticulitis
• severe hepatic impairment
• hypersensitivity to any component of the product

LOTRONEX (alosetron hydrochloride) should not be used by patients who are unable to understand or comply with the Patient-Physician Agreement for LOTRONEX (alosetron hydrochloride) .

Concomitant administration of alosetron with fluvoxamine is contraindicated. Fluvoxamine, a known strong inhibitor of CYP1A2, has been shown to increase mean alosetron plasma concentrations (AUC) approximately 6-fold and prolong the half-life by approximately 3-fold (see PRECAUTIONS: DRUG INTERACTIONS).

Last reviewed on RxList: 5/16/2008
This monograph has been modified to include the generic and brand name in many instances.