Tindamax (Tinidazole) - Oral

What Is Tindamax?

Tindamax (tinidazole) is an antibiotic drug prescribed to treat bacterial vaginosis. The drug also treats certain parasitic diseases (specifically amebiasis and giardiasis) and the sexually transmitted infection trichomoniasis.

Tindamax belongs to a class of drugs called nitroimidazole antibiotics that are able to fight not only bacteria, but certain protozoan parasites as well. Protozoa are single-celled organisms that can survive as free-living organisms or can multiply in humans and cause parasitic infections.

The drug works by penetrating the wall of bacteria and damaging both their DNA and structural proteins. It is unclear how Tindamax acts against protozoan infections.

Tindamax is available in tablet form for both adults and children older than 3 years. There are several lower-cost generics available under the drug name tinidazole.

Drug Facts

Generic Name: Tinidazole

Brand Name(s): Tindamax

Administration Route(s): Oral

Drug Availability: Prescription

Therapeutic Classification: Antibiotic

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Tinidazole

Dosage Form(s): Tablet

What Is Tindamax Used For?

Tindamax is used to treat infections caused by specific susceptible bacteria or protozoa. They do not work against all bacteria and protozoa, but mainly those with anaerobic properties (meaning that they don’t need oxygen to survive).

The Food and Drug Administration approved Tindamax to treat:

  • Amebiasis, a diarrheal disease caused by the intestinal protozoa Entamoeba histolytica
  • Bacterial vaginosis, a bacterial infection of the vulva and vagina
  • Giardiasis, a diarrheal disease caused by the intestinal protozoan Giardia duodenalis
  • Trichomoniasis, a sexually transmitted infection caused by the protozoa Trichomonas vaginalis

Tindamax only acts against susceptible bacteria and parasites. Your healthcare provider should identify the disease-causing organism for your infection and rule out all other causes (including vaginal yeast infections and sexually transmitted diseases like chlamydia, gonorrhea, and genital herpes).

Tindamax may be ineffective when used without proven or suspected bacterial infection. Unnecessary use of antibiotics like Tindmax can also contribute to the development of antibiotic resistance.

How to Take Tindamax

Tindamax is available as 500-milligram (mg), pink, oval tablets. The tablets are scored so that they can be split. Some generic manufacturers produce 250 mg tablets.

Depending on the infection, Tindamax may require only a single dose (for giardiasis and trichomoniasis) or up to five doses over five consecutive days (for amebiasis and bacterial vaginosis).


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Tindamax is taken by mouth with food, which helps reduce stomach upset. If you need more than one dose, be sure to take the dose at the same time every day. Regular dosing helps maintain the right amount of tinidazole in the bloodstream.

Avoid drinking alcohol while taking Tindamax and for three days after completing therapy. Taking Tindamax with alcohol can lead to abdominal cramps, nausea, vomiting, headaches, and flushing.

If you or your child are unable to swallow pills, your pharmacist can compound the medication into a liquid suspension, typically using a cherry-flavored syrup.

It is important to take the full course of antibiotics even if you start to feel better. Stopping early can lead to antibiotic resistance, making Tindamax (and related antibiotics like metronidazole) far less effective if it is ever needed again.


Store Tindamax tablets at room temperature, ideally between 68 F and 77 F. Compounded Tindamax syrup can also be stored at this temperature but must be used within seven days of preparation by your pharmacist.

Avoid keeping the tablets or syrup on a sunny windowsill or in your glove compartment where temperatures can be excessive. If you need to take Tindamax with you on a trip, it is OK to expose the drug to temperatures of 59 F to 86 F.

Off-Label Uses

Healthcare providers may prescribe Tindamax to treat other medical conditions not listed on the product label. This is known as off-label use. 

Tindamax is used off-label for many medical purposes, including prophylactic (preventive) therapies. These include:

What Are the Side Effects of Tindamax?

This is not a complete list of side effects, and others may occur. A medical professional can advise you on side effects. If you experience other effects, contact your pharmacist or a medical professional. You may report side effects to the FDA atwww.fda.gov/medwatch or 1-800-FDA-1088.

As with many other medications, Tindamax may cause side effects. Most involve the gastrointestinal tract, which can be minimized by taking the drug with food. Other rare and potentially serious drug reactions have been reported. Even so, Tindamax is generally well tolerated when used for one to five days.

Common Side Effects

Common side effects include (by order of frequency):

The risk of side effects increases with the duration of therapy.

Moreover, research showed around one in 20 women treated for bacterial vaginosis with Tindamax experienced a yeast infection following treatment due to changes in the natural vaginal flora.

Severe Side Effects

On rare occasions, Tindamax has been known to trigger potentially severe neurological side effects, including seizures and peripheral neuropathy (numbness or pins-and-needles sensations in the hands or feet). Let your healthcare provider know immediately if any unusual nerve-related symptoms develop. They may recommend you stop treatment.

Arguably, the greater concern is the risk of drug hypersensitivity, which may not only affect first-time users but those previously treated with Tindamax. While these reactions are exceptionally rare, some are potentially life-threatening.

Reported drug reactions have included:

Call your provider right away if you have serious side effects while taking Tindamax. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. These include symptoms of anaphylaxis, such as:

If not treated immediately, anaphylaxis can lead to shock, coma, heart or respiratory failure, and death.

Long-Term Side Effects

The main concern about the overuse of Tindamax is the risk of antibiotic resistance.

Although this is more commonly associated with Flagyl (metronidazole), which is an earlier generation nitroimidazole, growing resistance to Tindamax has been seen among people treated for Trichomonas vaginalis.

Report Side Effects

Tindamax may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your provider may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Tindamax Should I Take?

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The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For amebic liver abscess:
      • Adults—2 grams (g) once a day for 3 to 5 days.
      • Children older than 3 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 50 milligrams (mg) per kilogram (kg) of body weight per day (up to 2 g per day) for 3 to 5 days.
      • Children 3 years of age and younger—Use and dose must be determined by your doctor.
    • For bacterial vaginosis:
      • Adults— 2 grams (g) once a day for 2 days or 1 g once a day for 5 days.
      • Children—Use and dose must be determined by your doctor.
    • For giardiasis:
      • Adults—2 grams (g) given as a single dose.
      • Children older than 3 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 50 milligrams (mg) per kilogram (kg) of body weight (up to 2 g) given as a single dose.
      • Children 3 years of age and younger—Use and dose must be determined by your doctor.
    • For intestinal amebiasis:
      • Adults—2 grams (g) once a day for 3 days.
      • Children older than 3 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 50 milligrams (mg) per kilogram (kg) of body weight per day (up to 2 g per day) for 3 days.
      • Children 3 years of age and younger—Use and dose must be determined by your doctor.
    • For trichomoniasis:
      • Adults— 2 grams (g) given once as a single dose.
      • Children—Use and dose must be determined by your doctor.


Tindamax is mainly metabolized (broken down) by the liver and excreted from the body in urine and stool. Because the course of treatment is short, the drug doesn’t have any notable effect on either kidney function or liver function.

With that said, people with end-stage kidney disease may lose as much as 43% of the circulating drug during hemodialysis. There are currently no guidelines directing the appropriate use of Tindamax in cases like this. Your healthcare provider will decide if your dose needs to be changed.

Missed Dose

If you miss a dose of Tindamax, take it as soon as you remember. If it is almost time for your next dose, skip the original dose and continue as normal. Never double-up doses.

Because the half-life of Tindamax is relatively short (12 to 14 hours), you need to make every effort to take the drug on schedule. Try to take it at the same time every day to maintain the optimal drug concentration in the blood.

To avoid missing doses, set a daily alarm on your cell phone and/or ask a friend or family member to serve as an “adherence buddy” during treatment.

Overdose: What Happens If I Take Too Much Tindamax?

According to the manufacturer, there are no reported cases of a Tindamax overdose.1 If one does occur—say, if someone takes all their pills at once—the risk of side effects might increase.

In such instances, supportive care can help treat side effects like upset stomach, nausea, or vomiting. If more significant side effects occur, hemodialysis could be used to quickly remove as much of the drug from the bloodstream.

What Happens If I Overdose on Tindamax?

If you think you or someone else may have overdosed on Tindamax, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Tindamax, call 911 immediately.


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It is important that your doctor check your progress at regular visits to make sure that the infection is cleared up. Blood tests may be needed to check for unwanted effects.

If your symptoms do not improve within a few days, or if they become worse, check with your doctor.

Do not use this medicine if you have taken disulfiram (Antabuse®) within the last two weeks. Also, do not take alcohol or alcoholic products (eg, propylene glycol) during treatment with this medicine and for at least 3 days after your last dose.

This medicine may increase your risk for cancer. Talk to your doctor about this risk.

Check with your doctor right away if you have burning, numbness, tingling, or painful sensations in the arms, hands, legs, or feet. These could be symptoms of a condition called peripheral neuropathy.

This medicine may cause a vaginal yeast infection. Check with your doctor right away if you have itching of the vagina or genitals or thick, white vaginal discharge with mild or no odor.

If you are taking this medicine for trichomoniasis(an infection of the sex organs in men or women), your doctor may want to treat your sexual partner at the same time you are being treated, even if he or she has no symptoms. Also, it may be desirable to use a condom (rubber) during intercourse. These measures will help to keep you from getting the infection back again from your partner. If you have any questions about this, talk with your doctor.

If you plan to have children, talk with your doctor before using this medicine. Some men using this medicine have become infertile (unable to have children).

Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests may be affected by this medicine.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn’t Take Tindamax?

You should not take Tindamax if you have a known hypersensitivity to tinidazole or any other ingredient in the drug. The same applies if you have a hypersensitive reaction to other nitroimidazole antimicrobials like Flagyl (metronidazole), Dovprela (pretomanid), Solosec (secnidazole), and fexinidazole.

Based on the available evidence, Tindamax does not appear to pose significant health risks to an unborn baby during pregnancy. Animal studies have shown no evidence of birth defects or pregnancy complications when Tindamax was delivered at three to six times the maximum dose used in humans.

Even so, if you are pregnant or trying to get pregnant, speak with your healthcare provider to fully understand the benefits and potential risks of treatment.

Studies have shown that tinidazole can pass through human breast milk. Because of this, temporarily stop breastfeeding during treatment and for 72 hours after treatment to fully clear the medication from your system.

What Other Medications Interact With Tindamax?

A number of drugs can potentially interact with Tindamax. Some might decrease the concentration of tinidazole in the blood (reducing its effectiveness), while others might increase the concentration (along with the risk of side effects).

There are also drugs that may “compete” for the same liver enzyme—called CYP450—that Tindamax uses for metabolization.

Let your healthcare provider know if you use any of the following before starting Tindamax:

To avoid interactions, always tell your healthcare provider about any drugs you take, whether they are prescription, over-the-counter, nutritional, herbal, or recreational.

What Medications Are Similar?

Tindamax is classified as a second-generation nitroimidazole and is often used as an alternative to the first-generation nitroimidazole Flagyl (metronidazole). It treats a broader range of bacterial infections, including serious bone, joint, brain, skin, heart, gastrointestinal, and lung infections.

Flagyl generally remains the drug of choice for bacterial vaginosis and other bacterial infections. Even so, it requires a higher dose and dose frequency (in some cases, up to six doses per day for 10 days). It is also more likely to cause side effects.

Tindamax is typically used when Flagyl is either unavailable or causes intolerable side effects. However, some health providers will prescribe it as the first therapy if a susceptible bacteria is identified.

In 2017, the FDA approved a newer nitroimidazole agent, called Solosec (secnidazole), specifically used for the treatment of bacterial vaginosis. Other nitroimidazole agents, like Dovprela (pretomanid) and fexinidazole, are indicated for the treatment of multidrug-resistant tuberculosis and African sleeping sickness, respectively.

Frequently Asked Questions

  • What is Tindamax used for?

    Tindamax (tinidazole) is an antibiotic used to treat bacterial vaginosis, the sexually transmitted infection trichomoniasis, and the diarrheal parasitic diseases amebiasis and giardiasis.

  • Is Tindamax better than Flagyl?

    Although Tindamax (tinidazole) and Flagyl (metronidazole) are closely related, Flagyl remains the drug of choice in most cases because it is able to treat a broader range of infections. Even so, Tindamax has a longer half-life, requires a lower dose, and causes fewer side effects than Flagyl. In cases where Flagyl is either unavailable or intolerable, Tindamax may be the better option.

  • What are the side effects of Tindamax?

    Tindamax is generally well tolerated, although it may cause side effects in some. Most are relatively mild and will resolve once treatment is completed. The most common side effects include:

    • A metallic or bitter taste in the mouth
    • Fatigue
    • Loss of appetite
    • Stomach upset or cramps
    • Headache
    • Dizziness
    • Nausea or vomiting
  • How do I take Tindamax?

    Take Tindamax by mouth once daily. Take it with food to reduce the risk of nausea and other gastrointestinal side effects. Avoid drinking alcohol during treatment (and for three days after) as it can cause nausea, vomiting, stomach cramps, headaches, and flushing.

  • Can Tindamax cause a drug allergy?

    All antibiotics have the potential to cause an allergy, but the risk of a severe allergy with Tindamax is extremely low. According to most national drug allergy registries, only a handful of cases of anaphylaxis—a potentially life-threatening, whole-body allergy—have ever been reported for either Tindamax or the closely related antibiotic Flagyl (metronidazole).

How Can I Stay Healthy While Taking Tindamax?

If you are prescribed Tindamax, it is because you have a specific bacterial or parasitic infection. To ensure the optimal response, it is up to you to take the drug as prescribed. Never stop early no matter how well you may feel; doing so can lead to antibiotic resistance.

If you are being treated for trichomoniasis, it is important to get your sex partner tested and treated if they test positive. The same consideration should be made if you have bacterial vaginosis and a female sex partner. Male sex partners don’t require testing or treatment.

If you have been diagnosed with amebiasis or giardiasis, it is important to stay healthy by ensuring ample hydration and eating a soft, plain diet until you are recovered. To avoid infecting others, wash your hands after using the bathroom and before preparing meals, clean toilet seats and surfaces regularly, and avoid sharing towels or face cloths.

Medical Disclaimer

Verywell Health's drug information is meant for education purposes only and not intended as a replacement for medical advice, diagnosis, or treatment from a healthcare professional. Consult your doctor before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

22 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By James Myhre & Dennis Sifris, MD
Dennis Sifris, MD, is an HIV specialist and Medical Director of LifeSense Disease Management. James Myhre is an American journalist and HIV educator.