Tinidazole 500mg Tablets
WARNING: A drug like this one has been shown to cause cancer in mice and rats. It is not known if this drug may cause this effect in humans. If you have questions, talk with the doctor.The doctor has given you this drug for a certain health problem. Do not use this drug for other health problems.Do not take this drug for longer than you were told by your doctor. @ COMMON USES: It is used to treat infections.
Drug Class
Antiprotozoal, Antibacterial
Pharmacologic Class
Nitroimidazole
Pregnancy Category
Category C
FDA Approved
May 2004
DEA Schedule
Not Controlled
Overview
What is this medicine?
Tinidazole is an antibiotic that treats certain types of infections caused by bacteria and parasites. It works by stopping the growth of these harmful organisms. It's often used for vaginal infections, giardiasis, and amebiasis.
How to Use This Medicine
Taking Your Medication
To take this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with food to help prevent stomach upset. If you have trouble swallowing pills, you can ask your doctor or pharmacist about creating a liquid suspension.
If a liquid suspension is prepared, make sure to shake it well before each use. When measuring liquid doses, use the measuring device that comes with the medication. If one is not provided, ask your pharmacist for a suitable measuring device to ensure accurate dosing.
Storing and Disposing of Your Medication
Store your medication at room temperature, away from light and in a dry place. Avoid storing it in a bathroom. If a liquid suspension is made from tablets, discard any unused portion after 7 days. Keep all medications in a safe location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take two doses at the same time or take extra doses. For certain infections, you may be prescribed a single dose, so be sure to follow your doctor's instructions carefully.
To take this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication with food to help prevent stomach upset. If you have trouble swallowing pills, you can ask your doctor or pharmacist about creating a liquid suspension.
If a liquid suspension is prepared, make sure to shake it well before each use. When measuring liquid doses, use the measuring device that comes with the medication. If one is not provided, ask your pharmacist for a suitable measuring device to ensure accurate dosing.
Storing and Disposing of Your Medication
Store your medication at room temperature, away from light and in a dry place. Avoid storing it in a bathroom. If a liquid suspension is made from tablets, discard any unused portion after 7 days. Keep all medications in a safe location, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so. If you have questions about disposing of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and continue with your regular dosing schedule. Do not take two doses at the same time or take extra doses. For certain infections, you may be prescribed a single dose, so be sure to follow your doctor's instructions carefully.
Lifestyle & Tips
- DO NOT consume alcohol or alcohol-containing products (e.g., cough syrups, mouthwash) during treatment and for at least 3 days after stopping tinidazole. This can cause severe nausea, vomiting, abdominal cramps, and flushing.
- Take with food to minimize stomach upset.
- Complete the full course of medication as prescribed, even if symptoms improve, to prevent recurrence and resistance.
- Avoid driving or operating machinery if you experience dizziness or vertigo.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
Varies by indication
Dose Range:
500 - 2000 mg
Condition-Specific Dosing:
Trichomoniasis:
2 g orally as a single dose
Giardiasis:
2 g orally as a single dose
Intestinal Amebiasis:
2 g orally once daily for 3 days
Amebic Liver Abscess:
1.5 g orally once daily for 3-5 days OR 2 g orally once daily for 3 days
Bacterial Vaginosis:
2 g orally as a single dose OR 1 g orally once daily for 5 days
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Giardiasis/Amebiasis: 50 mg/kg orally as a single dose (max 2 g)
Adolescent:
Dosing typically follows adult guidelines for specific indications if weight/age appropriate.
Dose Adjustments
Renal Impairment:
Mild:
No adjustment needed
Moderate:
No adjustment needed
Severe:
No adjustment needed, but caution advised due to limited data.
Dialysis:
Tinidazole is readily removed by hemodialysis. Administer after completion of hemodialysis.
Hepatic Impairment:
Mild:
No adjustment needed
Moderate:
No specific adjustment guidelines; use with caution and monitor for adverse effects.
Severe:
Reduced clearance and increased plasma half-life. Use with caution; consider dose reduction or extended dosing interval, and monitor for adverse effects.
Pharmacology
Mechanism of Action
Tinidazole is a nitroimidazole antimicrobial. It enters anaerobic cells and is reduced by ferredoxin-like proteins to reactive nitro radicals. These radicals damage DNA and other macromolecules, leading to cell death. This mechanism is effective against susceptible anaerobic bacteria and protozoa.
Pharmacokinetics
Absorption:
Bioavailability:
Nearly 100%
Tmax:
1-2 hours
FoodEffect:
Food delays Tmax but does not significantly affect AUC or Cmax.
Distribution:
Vd:
50 L
ProteinBinding:
Approximately 16%
CnssPenetration:
Yes
Elimination:
HalfLife:
12-14 hours
Clearance:
Not readily available (renal and non-renal clearance)
ExcretionRoute:
Renal (primarily) and fecal
Unchanged:
Approximately 20-25% (renal)
Pharmacodynamics
OnsetOfAction:
Rapid (within hours for single dose regimens)
PeakEffect:
Within 1-2 hours of administration
DurationOfAction:
Sustained plasma levels allow for single-dose or short-course regimens due to long half-life.
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
If you experience any of the following symptoms, call your doctor immediately or seek emergency medical attention, as they may be signs of a severe and potentially life-threatening reaction:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
A burning, numbness, or tingling feeling that is not normal
Seizures
Vaginal itching or discharge
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or do not go away, contact your doctor for advice:
Bad taste in your mouth
Upset stomach
Note: This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
If you experience any of the following symptoms, call your doctor immediately or seek emergency medical attention, as they may be signs of a severe and potentially life-threatening reaction:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
A burning, numbness, or tingling feeling that is not normal
Seizures
Vaginal itching or discharge
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. If you experience any of the following side effects or any other unusual symptoms that bother you or do not go away, contact your doctor for advice:
Bad taste in your mouth
Upset stomach
Note: This list is not exhaustive, and you may experience other side effects not mentioned here. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe allergic reaction (rash, itching/swelling, severe dizziness, trouble breathing)
- Numbness, tingling, pain, or weakness in hands or feet (signs of peripheral neuropathy)
- Seizures
- Severe or persistent diarrhea (may indicate C. difficile infection)
- Unusual bruising or bleeding
- Dark urine, yellowing of skin or eyes (signs of liver problems)
- Severe headache, stiff neck, fever, confusion (rare, but possible CNS effects)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have Cockayne syndrome, as some individuals with this condition have developed liver problems when taking similar medications. In some cases, these liver issues have been severe, persistent, or even fatal.
If you have taken disulfiram in the past 2 weeks, as this may interact with the medication.
If you are breastfeeding, as you should not breastfeed for at least 72 hours after receiving this medication.
Additionally, it is crucial to discuss all of your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. This includes any health problems you have, as they may interact with the medication. Do not start, stop, or change the dose of any medication without first consulting your doctor to ensure it is safe to do so.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the allergic reaction you experienced, including any symptoms that occurred.
If you have Cockayne syndrome, as some individuals with this condition have developed liver problems when taking similar medications. In some cases, these liver issues have been severe, persistent, or even fatal.
If you have taken disulfiram in the past 2 weeks, as this may interact with the medication.
If you are breastfeeding, as you should not breastfeed for at least 72 hours after receiving this medication.
Additionally, it is crucial to discuss all of your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. This includes any health problems you have, as they may interact with the medication. Do not start, stop, or change the dose of any medication without first consulting your doctor to ensure it is safe to do so.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This is crucial because it may interfere with certain laboratory tests. Be sure to notify all your healthcare providers and laboratory personnel that you are taking this drug.
To minimize potential interactions, you may need to avoid consuming alcohol and products containing alcohol or propylene glycol during treatment with this medication and for at least 72 hours after your last dose. Examples of products that may contain alcohol or propylene glycol include some cough syrups. Using these products while taking this drug can cause adverse effects such as stomach cramps, nausea, vomiting, headaches, and flushing. Consult your doctor to determine if you need to avoid alcohol and products containing alcohol or propylene glycol.
Do not take this medication for a longer duration than prescribed, as this may increase the risk of developing a second infection. If you are taking cholestyramine, you may need to take it at a different time than this medication; consult your pharmacist for guidance.
If you are being treated for a sexually transmitted disease, your partner may also require treatment. Discuss this with your doctor to ensure appropriate management.
This medication may affect fertility in males, so it is essential to discuss this potential risk with your doctor.
If you are pregnant or plan to become pregnant, inform your doctor, as they will need to weigh the benefits and risks of using this medication during pregnancy and discuss them with you.
To minimize potential interactions, you may need to avoid consuming alcohol and products containing alcohol or propylene glycol during treatment with this medication and for at least 72 hours after your last dose. Examples of products that may contain alcohol or propylene glycol include some cough syrups. Using these products while taking this drug can cause adverse effects such as stomach cramps, nausea, vomiting, headaches, and flushing. Consult your doctor to determine if you need to avoid alcohol and products containing alcohol or propylene glycol.
Do not take this medication for a longer duration than prescribed, as this may increase the risk of developing a second infection. If you are taking cholestyramine, you may need to take it at a different time than this medication; consult your pharmacist for guidance.
If you are being treated for a sexually transmitted disease, your partner may also require treatment. Discuss this with your doctor to ensure appropriate management.
This medication may affect fertility in males, so it is essential to discuss this potential risk with your doctor.
If you are pregnant or plan to become pregnant, inform your doctor, as they will need to weigh the benefits and risks of using this medication during pregnancy and discuss them with you.
Overdose Information
Overdose Symptoms:
- Nausea
- Vomiting
- Ataxia (loss of coordination)
- Peripheral neuropathy (numbness/tingling)
- Seizures
What to Do:
There is no specific antidote. Treatment is symptomatic and supportive. Contact a poison control center immediately (e.g., 1-800-222-1222 in the US) or seek emergency medical attention.
Drug Interactions
Contraindicated Interactions
- Alcohol (including alcohol-containing medications) due to disulfiram-like reaction
Major Interactions
- Warfarin (increased anticoagulant effect)
- Lithium (increased lithium levels and potential for toxicity)
- Phenytoin/Fosphenytoin (increased phenytoin levels)
- Cyclosporine (potential for increased cyclosporine levels)
Moderate Interactions
- Cimetidine (may prolong tinidazole half-life)
- Rifampin (may decrease tinidazole levels)
- Fluconazole (may increase tinidazole levels)
Monitoring
Baseline Monitoring
Liver Function Tests (LFTs)
Rationale: To establish baseline in patients with pre-existing hepatic impairment or for prolonged therapy.
Timing: Prior to initiation of therapy if indicated.
Complete Blood Count (CBC)
Rationale: To establish baseline, especially if prolonged therapy is anticipated, due to rare reports of transient leukopenia or neutropenia.
Timing: Prior to initiation of therapy if indicated.
Routine Monitoring
INR (International Normalized Ratio)
Frequency: Regularly, especially during and after tinidazole therapy
Target: Therapeutic range for patient's indication
Action Threshold: Significant increase above target range; adjust warfarin dose as needed.
Lithium levels
Frequency: Regularly, especially during and after tinidazole therapy
Target: Therapeutic range for patient's indication
Action Threshold: Increase above therapeutic range; adjust lithium dose as needed.
Symptom Monitoring
- Signs of disulfiram-like reaction (nausea, vomiting, abdominal cramps, flushing, headache) if alcohol is consumed.
- Signs of central nervous system (CNS) effects (seizures, peripheral neuropathy, dizziness, vertigo, ataxia).
- Signs of severe skin reactions (e.g., Stevens-Johnson syndrome, toxic epidermal necrolysis).
- Signs of superinfection (e.g., new or worsening diarrhea, oral thrush, vaginal yeast infection).
- Signs of hepatic dysfunction (e.g., jaundice, dark urine, persistent nausea/vomiting).
Special Patient Groups
Pregnancy
Category C. Avoid during the first trimester. Use during the second and third trimesters only if clearly needed and the potential benefits outweigh the potential risks to the fetus.
Trimester-Specific Risks:
First Trimester:
Avoid due to potential for teratogenicity observed in animal studies with related compounds.
Second Trimester:
Use with caution; limited human data.
Third Trimester:
Use with caution; limited human data.
Lactation
Tinidazole is excreted into breast milk. Discontinue breastfeeding during treatment and for at least 72 hours (3 days) after the last dose of tinidazole to minimize infant exposure.
Infant Risk:
L3 (Moderate risk). Potential for gastrointestinal upset (diarrhea, candidiasis), and theoretical risk of carcinogenicity based on animal data with related compounds.
Pediatric Use
Approved for use in children 3 years of age and older for giardiasis and amebiasis. Dosing is weight-based. Safety and efficacy in children younger than 3 years have not been established.
Geriatric Use
No specific dose adjustment is required based on age alone. However, elderly patients may have reduced renal or hepatic function, which should be considered. Monitor for adverse effects, especially CNS effects, as elderly patients may be more susceptible.
Clinical Information
Clinical Pearls
- Always emphasize the strict alcohol avoidance rule to patients, as the disulfiram-like reaction can be very unpleasant.
- Tinidazole has a longer half-life than metronidazole, allowing for single-dose or shorter-course regimens, which can improve patient adherence.
- Advise patients to take tinidazole with food to reduce gastrointestinal side effects like nausea and metallic taste.
- Consider tinidazole as an alternative for patients who do not tolerate metronidazole due to different adverse effect profiles, though some side effects are similar due to class.
- For amebic liver abscess, tinidazole should be used in conjunction with drainage of the abscess if indicated.
Alternative Therapies
- Metronidazole (for trichomoniasis, giardiasis, amebiasis, bacterial vaginosis, anaerobic infections)
- Secnidazole (for bacterial vaginosis, trichomoniasis, giardiasis)
- Nitazoxanide (for giardiasis, cryptosporidiosis)
- Paromomycin (for intestinal amebiasis, giardiasis in pregnancy)
- Iodoquinol (for intestinal amebiasis)
Cost & Coverage
Average Cost:
Varies widely, typically $50-$300 per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 for generic; Tier 3 or higher for brand
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.