SIDE EFFECTS: Diarrhea, nausea, vomiting, dry mouth, headache, dizziness, drowsiness, or vaginal dryness/burning may occur. If any of these effects persist or worsen, notify your doctor. Tell your doctor immediately if any of these unlikely but serious side effects occur: stomach pain, tingling or numbness of the hands/feet, seizures. Tell your doctor immediately if any of these highly unlikely but very serious side effects occur: chest pain, mental/mood changes. An allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, trouble breathing. This medication may cause your urine to darken in color. This harmless effect is temporary and will disappear when the medication is stopped. If you notice other effects not listed above, contact your doctor or pharmacist.

PRECAUTIONS: This medication is not recommended for use if you have the following medical conditions: nervous system (neurological) disorders (e.g., seizures, neuropathy), blood problems (e.g., low red and/or white blood cell counts), low blood thyroid levels (hypothyroidism), adrenal gland problem (hypoadrenalism). Tell your doctor your medical history, especially of: liver problems, any allergies. This drug may make you dizzy or drowsy; use caution engaging in activities requiring alertness such as driving or using machinery. Avoid alcoholic beverages. Also, alcohol use combined with this medication may increase your risk of certain side effects (e.g., vomiting, stomach upset, vision problems). This medication should be used only if clearly needed during pregnancy. Discuss the risks and benefits with your doctor. This medication passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Tell your doctor of all prescription and nonprescription medication you may use, especially: disulfiram, lithium, "blood thinners" (e.g., warfarin), certain anti-seizure medicine (e.g., phenobarbital, phenytoin), fluorouracil. This drug may interfere with certain laboratory tests (e.g., liver function tests). Do not start or stop any medicine without doctor or pharmacist approval.

Report Problems to the Food and Drug Administration You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088. Need help identifying pills and medications? Use the pill identifier tool on RxList.