Also found in: Dictionary.
Pharmacologic class: Antiprotozoal
Therapeutic class: Anti-infective
Pregnancy risk category C
FDA Box Warning
Prolonged use of metronidazole (a structurally related drug with similar biologic effects) has caused cancer in mice and rats. Reserve tinidazole for conditions listed under "Indications and dosages."
Free nitro radical (generated from tinidazole reduction by Trichomonas cell extracts) may explain activity against Trichomonas species; activity against Giardia and Entamoeba species is unknown.
Tablets: 250 mg, 500 mg
Indications and dosages
➣ Trichomoniasis caused by Trichomonas vaginalis
Adults: Single dose of 2 g P.O. with food, given to both sexual partners simultaneously
➣ Bacterial vaginosis in nonpregnant females
Adults: 2 g P.O. once daily with food for 2 days, or 1 g P.O. once daily with food for 5 days
➣ Giardiasis caused by Giardia duodenalis (Giardia lamblia)
Adults: Single dose of 2 g P.O. with food
Children older than age 3: Single dose of 50 mg/kg (up to 2 g) with food
➣ Amebiasis caused by Entamoeba histolytica
Adults: 2 g P.O. daily with food for 3 days
Children older than age 3: 50 mg/kg (up to 2 g) P.O. daily with food for 3 days
➣ Amebic liver abscess caused by E. histolytica
Adults: 2 g P.O. daily with food for 3 to 5 days
Children older than age 3: 50 mg/kg (up to 2 g) P.O. daily with food for 3 to 5 days
• Hemodialysis patients
• Hypersensitivity to drug, its components, or other nitroimidazole derivatives
• First trimester of pregnancy
Use cautiously in:
• CNS disease, hepatic dysfunction
• history of blood dyscrasias
• elderly patients
• pregnant or breastfeeding patients
• children (except to treat giardiasis and amebiasis in children older than age 3).
• Give with food to minimize GI discomfort.
CNS: weakness, fatigue, malaise, dizziness, vertigo, ataxia, insomnia, drowsiness, giddiness, headache, transient peripheral neuropathy, seizures
GI: nausea, vomiting, diarrhea, constipation, dyspepsia, gastric discomfort, tongue discoloration, stomatitis, anorexia
Hematologic: transient neutropenia and leukopenia
Musculoskeletal: arthralgia, myalgia, arthritis
Other: altered taste, overgrowth of susceptible organisms, hypersensitivity reactions including angioedema
Drug-drug. Cyclosporine, lithium, tacrolimus: possible increase in blood levels of these drugs
Cholestyramine: decreased oral bioavailability of tinidazole
CYP450 inducers (such as phenobarbital, rifampin): increased tinidazole elimination and decreased blood level
CYP450 inhibitors (such as cimetidine, ketoconazole): increased tinidazole blood level
Fluorouracil: decreased fluorouracil clearance
Fosphenytoin, phenytoin: prolonged half-life and reduced clearance of these drugs
Oxytetracycline: antagonism of therapeutic effects of tinidazole
Warfarin, other oral coumarin anticoagulants: increased effects of these drugs
Drug-diagnostic tests. Alanine aminotransferase, aspartate aminotransferase, hexokinase glucose, lactate dehydrogenase, triglycerides: interference with test results
Drug-behaviors. Alcohol use: disulfiram-like reaction during tinidazole therapy and for 3 days after
Closely monitor patient for neurologic abnormalities, such as seizures and peripheral neuropathy. If these occur, withdraw drug immediately.
• Monitor blood chemistry tests, especially liver function tests.
• Advise patient to take drug with food.
• For child or other patient unable to swallow tablets, inform parent or caregiver that drug can be crushed in artificial cherry syrup and given with food.
Caution patient or caregiver to stop therapy and call prescriber immediately if seizures or numbness or tingling in extremities occurs.
• Instruct patient to avoid alcohol use during therapy.
• Advise female patient to avoid pregnancy during therapy.
• Counsel female patient to avoid breastfeeding during therapy and for 3 days after last dose.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, and behaviors mentioned above.