Do NOT use Tinidazole if:

• you are allergic to any ingredient in Tinidazole or to other nitroimidazole medicines (metronidazole)
• you have the blood disease porphyria
• you are in your first 3 months of pregnancy
• you are taking astemizole, busulfan, cisapride, or terfenadine
• you have taken disulfiram within the past 2 weeks.

Contact your doctor or health care provider right away if any of these apply to you.

Some medical conditions may interact with Tinidazole. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

• if you are pregnant, planning to become pregnant, or are breast-feeding
• if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
• if you have allergies to medicines, foods, or other substances
• if you have nerve, brain, or blood problems; a yeast infection; or a history of seizures or liver problems
• if you are undergoing dialysis.

Some medicines may interact with Tinidazole. Tell your health care provider if you are taking any other medicines, especially any of the following:

• Azole antifungals (eg, ketoconazole) or cimetidine because they may increase the risk of Tinidazole's side effects
• Barbiturates (eg, phenobarbital), phenytoin, or rifampin because they may decrease Tinidazole's effectiveness
• Anticoagulants (eg, warfarin), astemizole, busulfan, cisapride, cyclosporine, fluorouracil, lithium, macrolide immunosuppressants (eg, tacrolimus), sulfonylureas (eg, glipizide), or terfenadine because their actions and the risk of their side effects may be increased
• Disulfiram because side effects, such as mental or mood changes, may occur
• Oral contraceptives (birth control pills) because their effectiveness may be decreased by Tinidazole.

This may not be a complete list of all interactions that may occur. Ask your health care provider if Tinidazole may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

Important safety information:

• Tinidazole may cause drowsiness or dizziness. These effects may be worse if you take it with alcohol or certain medicines. Use Tinidazole with caution. Do not drive or perform other possible unsafe tasks until you know how you react to it.
• Avoid drinking alcohol or taking products that contain alcohol while taking Tinidazole and for 3 days after the last dose.
• Tinidazole only works against bacteria and parasites; it does not treat viral infections (eg, the common cold).
• Be sure to use Tinidazole for the full course of treatment. If you do not, the medicine may not clear up your infection completely. The bacteria or parasites could also become less sensitive to this or other medicines. This could make the infection harder to treat in the future.
• Tinidazole may discolor or darken the urine. This is normal and not a cause for concern.
• Hormonal birth control (eg, birth control pills) may not work as well while you are using Tinidazole. To prevent pregnancy, use an extra form of birth control (eg, condoms).
• Tell your doctor or dentist that you take Tinidazole before you receive any medical or dental care, emergency care, or surgery.
• Tinidazole may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking Tinidazole.
• Lab tests, including blood cell counts, may be performed while you use Tinidazole. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
• Use Tinidazole with extreme caution in children younger 3 years; safety and effectiveness in these children have not been confirmed.
• Pregnancy and breast-feeding: Tinidazole may cause harm to the fetus. Tinidazole should not be used during the first trimester of pregnancy. If you think you may be pregnant, contact your doctor. You will need to discuss the benefits and risks of using Tinidazole while you are pregnant. Tinidazole is found in breast milk. Do not breast-feed while taking Tinidazole and for 3 days after you have taken the last dose.

All medicines may cause side effects, but many people have no, or minor, side effects.

Check with your doctor if any of these most common side effects persist or become bothersome:

Constipation; diarrhea; dizziness; general body discomfort; headache; loss of appetite; metallic/bitter taste in mouth; nausea; stomach pain; tiredness; vomiting; weakness.

Seek medical attention right away if any of these severe side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); abnormal skin sensations (prickling, tingling); depression; fever, chills, or persistent sore throat; hoarseness; irregular heartbeat; numbness or loss of feeling in the hands or feet; pounding in the chest; red, swollen, blistered, or peeling skin; seizures; shortness of breath; unusual bruising or bleeding ; vaginal irritation or discharge.

 This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider.