Metronidazole 500 mg Tablet, 20-count
🆔 Identity & classification
Where does this data come from?
🏷️ RxNorm drug class
This medicine belongs to the Nitroimidazole Antimicrobial class.
Where does this data come from?
🏭 Manufacturer & labeler
Where does this data come from?
🩺 Clinical
Metronidazole is used to treat certain infections in the body caused by bacteria including sexually transmitted diseases (STDs) and bacterial vaginosis (an infection caused by too much of certain types of harmful bacteria in the vagina) in women. Metronidazole is in a class of medications called nitroimidazole antimicrobials. It works by stopping the growth of bacteria. Antibiotics will not work for colds, flu, or other viral infections. Using antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.
Read the full MedlinePlus article ↗- This is one of the most important things to know about metronidazole. If you drink alcohol — or consume products containing propylene glycol — while taking it, you can have a prett...
- Why do I have to avoid alcohol while taking this?
- Yes, completely normal and actually really important. Trichomoniasis is a sexually transmitted infection, so even if your partner has no symptoms, they can still carry the parasite...
- My partner and I both have to take this for trichomoniasis — is that normal?
Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Metronidazole — tap one for details:
Metronidazole may be associated with lower levels of 7 nutrients — worth a chat with your pharmacist, not a cause for alarm.
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
💊 What it looks like
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🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 2S7830E561
Crospovidone is a synthetic polymer derived from povidone. It acts as a disintegrant, helping the tablet or capsule break apart quickly in the stomach so the active ingredient can be absorbed.
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UNII Z82Y2C65EA
Hydrogenated cottonseed oil is a solid fat made by adding hydrogen to cottonseed oil. It's used in medicines as a binder and lubricant to help hold ingredients together and make tablets easier to compress and release.
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UNII 66O7AQV0RT
Hydroxypropyl cellulose is a plant-derived thickener and binder made from cellulose. In medicines, it helps hold tablet ingredients together, thickens liquids, and can form a coating on pills or capsules.
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UNII OP1R32D61U
Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
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UNII ETJ7Z6XBU4
Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.
5 inactive ingredients listed in the exact product block matched to this NDC.
Where does this data come from?
ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per each | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | Not in the retail survey — common for institutional, discontinued, or low-volume packs. | |
| Medicaid paysCMS SDUD · 12 mo | No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data. | |
| Medicare drug plans payPart D · Q2 2026 | $0.2060 | $4.12 / 20 tablets |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Metronidazole 500 mg 00904-7126-61 | Major | 100 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 16571-0664-01 | Rising | 100 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 23155-0652-01 | Heritage | 100 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 29300-0227-01 | Unichem | 100 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 50111-0334-01 | Teva | 100 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 50268-0535-15 | AvPAK | 50 tablets | $0.101 | AB | Availability likely | — |
| metronidazole 500 mg 58657-0934-01 | Method | 100 tablets | $0.101 | — | Availability likely | — |
| Metronidazole 500 mg 60687-0550-01 | American | 100 tablets | $0.101 | — | Availability likely | — |
| Metronidazole 500 mg 62135-0796-90 | Chartwell | 90 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 68001-0365-00 | BluePoint | 100 tablets | $0.101 | AB | Availability likely | — |
| metronidazole 500 mg 72578-0008-01 | Viona | 100 tablets | $0.101 | AB | Availability likely | — |
| Metronidazole 500 mg 65862-0695-01 | Aurobindo | 100 tablets | $0.123 | AB | FDA listed | — |
| Metronidazole 500 mg 15955-0389-01 | Alembic | 100 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 46708-0429-30 | Alembic | 30 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 50090-0211-00 | A-S | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 50090-0212-01 | A-S | 30 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 50090-0213-00 | A-S | 14 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 51407-0372-01 | Golden | 100 tablets | — | — | FDA listed | — |
| Metronidazole 500 mg 51655-0441-20 | Northwind | 20 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 54348-0740-00 | PharmPak, | 1 tablet | — | AB | FDA listed | — |
| Metronidazole 500 mg 55154-8190-00 | Cardinal | 10 tablets | — | — | FDA listed | — |
| Metronidazole 500 mg 55700-0298-04 | Quality | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 60760-0336-14 | St. | 14 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 60760-0539-14 | ST. | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 61919-0032-10 | Direct_Rx | 10 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 62332-0017-30 | Alembic | 30 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 63187-0035-04 | Proficient | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 63187-0827-04 | Proficient | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 63629-1386-00 | Bryant | 40 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 63629-7916-01 | Bryant | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 67046-1060-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 67046-1173-03 | Coupler | 30 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 67296-0078-01 | Redpharm | 30 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 67296-2152-01 | Redpharm | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 68071-1876-00 | NuCare | 42 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 68071-2280-04 | NuCare | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 68071-2288-04 | NuCare | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 68071-2399-04 | NuCare | 4 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 68071-2409-01 | NuCare | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 68071-5073-02 | NuCare | 21 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 68788-7815-01 | Preferred | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 68788-8674-01 | Preferred | 14 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 69292-0208-01 | AMICI | 100 tablets | — | — | FDA listed | — |
| Metronidazole 500 mg 70518-0058-00 | REMEDYREPACK | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 70518-0088-02 | REMEDYREPACK | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 70518-1240-00 | REMEDYREPACK | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 70518-1241-00 | REMEDYREPACK | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 70518-2305-01 | REMEDYREPACK | 4 tablets | — | AB | Discontinued | — |
| metronidazole 500 mg 70518-2663-00 | REMEDYREPACK | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 70518-3110-00 | REMEDYREPACK | 30 tablets | — | AB | Discontinued | — |
| Metronidazole 500 mg 70518-3265-01 | REMEDYREPACK | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 70771-1046-01 | Zydus | 100 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 71209-0063-02 | Cadila | 50 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 71335-0358-00 | Bryant | 40 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mgthis 71335-1681-01 | Bryant | 20 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 71335-1703-00 | Bryant | 40 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 71335-1922-00 | Bryant | 40 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 71335-2640-01 | Bryant | 14 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 71335-2681-01 | Bryant | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 72162-2403-02 | Bryant | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 72789-0005-14 | PD-Rx | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 72789-0007-04 | PD-Rx | 4 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 72789-0011-04 | PD-Rx | 4 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 76420-0801-01 | Asclemed | 100 tablets | — | AB | FDA listed | — |
| metronidazole 500 mg 82868-0014-14 | Northwind | 14 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 82982-0072-14 | Pharmasource | 14 tablets | — | AB | Discontinued | — |
| metronidazole 500 mg 85766-0024-01 | Sportpharm | 100 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 85742-0025-24 | Kanchan | 50 tablets | — | AB | FDA listed | — |
| Metronidazole 500 mg 72162-2678-01 | Bryant | 100 tablets | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
🔬 Reported adverse events (FAERS)
Top reported reactions
Age at onset
Reporter sex
Serious outcomes
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📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 71335-1681-00 | 40 TABLET in 1 BOTTLE (71335-1681-0) | 2021-12-29 | Active |
| 71335-1681-01 You're viewing this | 20 TABLET in 1 BOTTLE (71335-1681-1) | 2020-08-05 | Active |
| 71335-1681-02 | 30 TABLET in 1 BOTTLE (71335-1681-2) | 2020-08-04 | Active |
| 71335-1681-03 | 14 TABLET in 1 BOTTLE (71335-1681-3) | 2020-08-05 | Active |
| 71335-1681-04 | 56 TABLET in 1 BOTTLE (71335-1681-4) | 2021-12-29 | Active |
| 71335-1681-05 | 21 TABLET in 1 BOTTLE (71335-1681-5) | 2020-08-10 | Active |
| 71335-1681-06 | 4 TABLET in 1 BOTTLE (71335-1681-6) | 2021-07-12 | Active |
| 71335-1681-07 | 28 TABLET in 1 BOTTLE (71335-1681-7) | 2020-08-31 | Active |
| 71335-1681-08 | 100 TABLET in 1 BOTTLE (71335-1681-8) | 2021-12-29 | Active |
| 71335-1681-09 | 60 TABLET in 1 BOTTLE (71335-1681-9) | 2021-12-29 | Active |
You're viewing one of 10 pack sizes for this product.
Pack size FAQ
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🧭 About this NDC listing & data coverage
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| NDC identity (package / product / labeler codes) | ✓ Available |
| Labeler | ✓ Available |
| Product & package description | ✓ Available |
| Marketing category & status | ✓ Available |
| Active ingredient / dosage form / route | ✓ Available |
| FDA label (SPL via DailyMed) | ✓ Available |
| Package photos | ✓ Available |
| Inactive ingredients (structured) | ✓ Available |
| NADAC pharmacy acquisition price (CMS) | — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey. |
| Orange Book / therapeutic-equivalence data | ✓ Available |
| HCPCS J-code billing crosswalk | — Not published for this NDC Most self-administered / retail products have no J-code — that is normal. |
| Medicaid utilization (CMS SDUD) | — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold. |
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📄 Full prescribing information FDA SPL
🚨 Boxed Warning ▾
WARNING Metronidazole has been shown to be carcinogenic in mice and rats (see PRECAUTIONS ). Unnecessary use of the drug should be avoided. Its use should be reserved for the conditions described in the INDICATIONS AND USAGE section below.
🎯 Indications and Usage ▾
INDICATIONS AND USAGE Symptomatic Trichomoniasis. Metronidazole tablets USP are indicated for the treatment of T. vaginalis infection in females and males when the presence of the trichomonad has been confirmed by appropriate laboratory procedures (wet smears and/or cultures). Asymptomatic Trichomoniasis.
Metronidazole tablets USP are indicated in the treatment of asymptomatic T. vaginalis infection in females when the organism is associated with endocervicitis, cervicitis, or cervical erosion. Since there is evidence that presence of the trichomonad can interfere with accurate assessment of abnormal cytological smears, additional smears should be performed after eradication of the parasite. Treatment of Asymptomatic Sexual Partners.
T. vaginalis infection is a venereal disease. Therefore, asymptomatic sexual partners of treated patients should be treated simultaneously if the organism has been found to be present, in order to prevent reinfection of the partner. The decision as to whether to treat an asymptomatic male partner who has a negative culture or one for whom no culture has been attempted is an individual one.
In making this decision, it should be noted that there is evidence that a woman may become reinfected if her sexual partner is not treated. Also, since there can be considerable difficulty in isolating the organism from the asymptomatic male carrier, negative smears and cultures cannot be relied upon in this regard. In any event, the sexual partner should be treated with metronidazole tablets USP in cases of reinfection.
Amebiasis. Metronidazole tablets USP are indicated in the treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess. In amebic liver abscess, metronidazole tablet USP therapy does not obviate the need for aspiration or drainage of pus.
Anaerobic Bacterial Infections. Metronidazole tablets USP are indicated in the treatment of serious infections caused by susceptible anaerobic bacteria. Indicated surgical procedures should be performed in conjunction with metronidazole tablets USP therapy.
In a mixed aerobic and anaerobic infection, antimicrobials appropriate for the treatment of the aerobic infection should be used in addition to metronidazole tablets USP. INTRA-ABDOMINAL INFECTIONS, including peritonitis, intra-abdominal abscess, and liver abscess, caused by Bacteroides species including the B. fragilis group ( B. fragilis, B. distasonis, B. ovatus, B. thetaiotaomicron, B. vulgatus ), Clostridium species, Eubacterium species, Peptococcus species, and Peptostreptococcus species. SKIN AND SKIN STRUCTURE INFECTIONS caused by Bacteroides species including the B. fragilis group, Clostridium species, Peptococcus species, Peptostreptococcus species, and Fusobacterium species.
GYNECOLOGIC INFECTIONS, including endometritis, endomyometritis, tubo-ovarian abscess, and postsurgical vaginal cuff infection, caused by Bacteroides species including the B. fragilis group, Clostridium species, Peptococcus species, Peptostreptococcus species, and Fusobacterium species. BACTERIAL SEPTICEMIA caused by Bacteroides species including the B. fragilis group and Clostridium species. BONE AND JOINT INFECTIONS, (as adjunctive therapy), caused by Bacteroides species including the B. fragilis group.
CENTRAL NERVOUS SYSTEM (CNS) INFECTIONS, including meningitis and brain abscess, caused by Bacteroides species including the B. fragilis group. LOWER RESPIRATORY TRACT INFECTIONS, including pneumonia, empyema, and lung abscess, caused by Bacteroides species including the B. fragilis group. ENDOCARDITIS caused by Bacteroides species including the B. fragilis group.
To reduce the development of drug-resistant bacteria and maintain the effectiveness of metronidazole tablets USP and other antibacterial drugs, metronidazole tablets USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are…
⏱️ Dosage and Administration ▾
DOSAGE AND ADMINISTRATION Trichomoniasis: In the Female: One-day treatment − two grams of metronidazole tablets, given either as a single dose or in two divided doses of one gram each, given in the same day. Seven-day course of treatment − 250 mg three times daily for seven consecutive days. There is some indication from controlled comparative studies that cure rates as determined by vaginal smears and signs and symptoms, may be higher after a seven-day course of treatment than after a one-day treatment regimen.
The dosage regimen should be individualized. Single-dose treatment can assure compliance, especially if administered under supervision, in those patients who cannot be relied on to continue the seven-day regimen. A seven-day course of treatment may minimize reinfection by protecting the patient long enough for the sexual contacts to obtain appropriate treatment.
Further, some patients may tolerate one treatment regimen better than the other. Pregnant patients should not be treated during the first trimester (see CONTRAINDICATIONS ). In pregnant patients for whom alternative treatment has been inadequate, the one-day course of therapy should not be used, as it results in higher serum levels which can reach the fetal circulation (see PRECAUTIONS, Pregnancy ).
When repeat courses of the drug are required, it is recommended that an interval of four to six weeks elapse between courses and that the presence of the trichomonad be reconfirmed by appropriate laboratory measures. Total and differential leukocyte counts should be made before and after re-treatment. In the Male: Treatment should be individualized as it is for the female.
Amebiasis Adults: For acute intestinal amebiasis (acute amebic dysentery): 750 mg orally three times daily for 5 to 10 days. For amebic liver abscess: 500 mg or 750 mg orally three times daily for 5 to 10 days. Pediatric patients : 35 to 50 mg/kg/24 hours, divided into three doses, orally for 10 days.
Anaerobic Bacterial Infections In the treatment of most serious anaerobic infections, intravenous metronidazole is usually administered initially. The usual adult oral dosage is 7.5 mg/kg every six hours (approx. 500 mg for a 70-kg adult).
A maximum of 4 g should not be exceeded during a 24-hour period. The usual duration of therapy is 7 to 10 days; however, infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment. Dosage Adjustments Patients with Severe Hepatic Impairment For patients with severe hepatic impairment (Child-Pugh C), the dose of metronidazole tablets should be reduced by 50% (see CLINICAL PHARMACOLOGY and PRECAUTIONS ).
Patients Undergoing Hemodialysis: Hemodialysis removes significant amounts of metronidazole and its metabolites from systemic circulation. The clearance of metronidazole will depend on the type of dialysis membrane used, the duration of the dialysis session, and other factors. If the administration of metronidazole cannot be separated from the hemodialysis session, supplementation of metronidazole dosage following the hemodialysis session should be considered, depending on the patient’s clinical situation (see CLINICAL PHARMACOLOGY ).
⛔ Contraindications ▾
CONTRAINDICATIONS Hypersensitivity Metronidazole tablets are contraindicated in patients with a prior history of hypersensitivity to metronidazole or other nitroimidazole derivatives. In patients with trichomoniasis, metronidazole tablets are contraindicated during the first trimester of pregnancy (see PRECAUTIONS ). Psychotic Reaction with Disulfiram Use of oral metronidazole is associated with psychotic reactions in alcoholic patients who were using disulfiram concurrently.
Do not administer metronidazole to patients who have taken disulfiram within the last two weeks (see PRECAUTIONS, Drug Interactions ). Interaction with Alcohol Use of oral metronidazole is associated with a disulfiram-like reaction to alcohol, including abdominal cramps, nausea, vomiting, headaches, and flushing. Discontinue consumption of alcohol or products containing propylene glycol during and for at least three days after therapy with metronidazole (see PRECAUTIONS, Drug Interactions ).
Cockayne Syndrome Metronidazole tablets are contraindicated in patients with Cockayne syndrome. Severe irreversible hepatotoxicity/acute liver failure with fatal outcomes have been reported after initiation of metronidazole in patients with Cockayne syndrome (see ADVERSE REACTIONS) .
⚠️ Warnings ▾
WARNINGS Hypersensitivity Reactions Hypersensitivity reactions including severe cutaneous adverse reactions (SCARs) can be serious and potentially life threatening (see ADVERSE REACTIONS ). Severe Cutaneous Adverse Reactions Severe cutaneous adverse reactions (SCARs) including toxic epidermal necrolysis (TEN), Stevens-Johnson syndrome (SJS), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) have been reported with the use of metronidazole. Symptoms can be serious and potentially life threatening (If symptoms or signs of SCARs develop, discontinue metronidazole tablets immediately and institute appropriate therapy.
Central and Peripheral Nervous System Effects Encephalopathy and peripheral neuropathy: Cases of encephalopathy and peripheral neuropathy (including optic neuropathy) have been reported with metronidazole. Encephalopathy has been reported in association with cerebellar toxicity characterized by ataxia, dizziness, and dysarthria. CNS lesions seen on MRI have been described in reports of encephalopathy.
CNS symptoms are generally reversible within days to weeks upon discontinuation of metronidazole. CNS lesions seen on MRI have also been described as reversible. Peripheral neuropathy, mainly of sensory type has been reported and is characterized by numbness or paresthesia of an extremity.
Convulsive seizures have been reported in patients treated with metronidazole. Aseptic meningitis: Cases of aseptic meningitis have been reported with metronidazole. Symptoms can occur within hours of dose administration and generally resolve after metronidazole therapy is discontinued.
The appearance of abnormal neurologic signs and symptoms demands the prompt evaluation of the benefit/risk ratio of the continuation of therapy (see ADVERSE REACTIONS ).
🤒 Adverse Reactions ▾
ADVERSE REACTIONS The following reactions have been reported during treatment with metronidazole: Central Nervous System: The most serious adverse reactions reported in patients treated with metronidazole have been convulsive seizures, encephalopathy, aseptic meningitis, optic and peripheral neuropathy, the latter characterized mainly by numbness or paresthesia of an extremity. Since persistent peripheral neuropathy has been reported in some patients receiving prolonged administration of metronidazole, patients should be specifically warned about these reactions and should be told to stop the drug and report immediately to their physicians if any neurologic symptoms occur.
In addition, patients have reported headache, syncope, dizziness, vertigo, incoordination, ataxia, tinnitus, hearing impairment, hearing loss, confusion, dysarthria, irritability, depression, weakness, and insomnia (see WARNINGS ). Gastrointestinal: The most common adverse reactions reported have been referable to the gastrointestinal tract, particularly nausea, sometimes accompanied by headache, anorexia, and occasionally vomiting; diarrhea; epigastric distress; and abdominal cramping and constipation. Mouth : A sharp, unpleasant metallic taste is not unusual.
Furry tongue, glossitis, and stomatitis have occurred; these may be associated with a sudden overgrowth of Candida which may occur during therapy. Dermatologic : Dermatitis bullous, fixed drug eruption, erythematous rash and pruritus. Hematopoietic : Reversible neutropenia (leukopenia); rarely, reversible thrombocytopenia.
Cardiovascular : QT prolongation has been reported, particularly when metronidazole was administered with drugs with the potential for prolonging the QT interval. Flattening of the T-wave may be seen in electrocardiographic tracings. Hypersensitivity : Toxic epidermal necrolysis (TEN), Stevens-Johnson Syndrome (SJS), drug reaction with eosinophilia and systemic symptoms (DRESS), acute generalized exanthematous pustulosis (AGEP) (see WARNINGS ), urticaria, erythematous rash, flushing, nasal congestion, dryness of the mouth (or vagina or vulva), and fever.
Renal : Dysuria, cystitis, polyuria, incontinence, and a sense of pelvic pressure. Instances of darkened urine have been reported by approximately one patient in 100,000. Although the pigment which is probably responsible for this phenomenon has not been positively identified, it is almost certainly a metabolite of metronidazole and seems to have no clinical significance.
Hepatic: Cases of severe irreversible hepatotoxicity/acute liver failure, including cases with fatal outcomes with very rapid onset after initiation of systemic use of metronidazole, have been reported in patients with Cockayne syndrome (latency from drug start to signs of liver failure as short as 2 days) (see CONTRAINDICATIONS ). Other : Proliferation of Candida in the vagina, dyspareunia, decrease of libido, proctitis, and fleeting joint pains sometimes resembling “serum sickness.” Rare cases of pancreatitis, which generally abated on withdrawal of the drug, have been reported.
Patients with Crohn’s disease are known to have an increased incidence of gastrointestinal and certain extraintestinal cancers. There have been some reports in the medical literature of breast and colon cancer in Crohn’s disease patients who have been treated with metronidazole at high doses for extended periods of time. A cause and effect relationship has not been established.
Crohn’s disease is not an approved indication for metronidazole tablets.
🆘 Overdosage ▾
OVERDOSAGE Single oral doses of metronidazole, up to 15 g, have been reported in suicide attempts and accidental overdoses. Symptoms reported include nausea, vomiting, and ataxia. Oral metronidazole has been studied as a radiation sensitizer in the treatment of malignant tumors.
Neurotoxic effects, including seizures and peripheral neuropathy, have been reported after 5 to 7 days of doses of 6 to 10.4 g every other day. Treatment of Overdosage: There is no specific antidote for metronidazole overdose; therefore, management of the patient should consist of symptomatic and supportive therapy.
🧬 Clinical Pharmacology ▾
CLINICAL PHARMACOLOGY Absorption Disposition of metronidazole in the body is similar for both oral and intravenous dosage forms. Following oral administration, metronidazole is well absorbed, with peak plasma concentrations occurring between one and two hours after administration. Plasma concentrations of metronidazole are proportional to the administered dose.
Oral administration of 250 mg, 500 mg, or 2,000 mg produced peak plasma concentrations of 6 mcg/mL, 12 mcg/mL, and 40 mcg/mL, respectively. Studies reveal no significant bioavailability differences between males and females; however, because of weight differences, the resulting plasma levels in males are generally lower. Distribution Metronidazole is the major component appearing in the plasma, with lesser quantities of metabolites also being present.
Less than 20% of the circulating metronidazole is bound to plasma proteins. Metronidazole appears in cerebrospinal fluid, saliva, and breast milk in concentrations similar to those found in plasma. Bactericidal concentrations of metronidazole have also been detected in pus from hepatic abscesses.
Metabolism/Excretion The major route of elimination of metronidazole and its metabolites is via the urine (60% to 80% of the dose), with fecal excretion accounting for 6% to 15% of the dose. The metabolites that appear in the urine result primarily from side-chain oxidation [1-(ß-hydroxyethyl)-2-hydroxymethyl-5-nitroimidazole and 2-methyl-5-nitroimidazole-1-yl-acetic acid] and glucuronide conjugation, with unchanged metronidazole accounting for approximately 20% of the total. Both the parent compound and the hydroxyl metabolite possess in vitro antimicrobial activity.
Renal clearance of metronidazole is approximately 10 mL/min/1.73 m 2 . The average elimination half-life of metronidazole in healthy subjects is eight hours. Renal Impairment Decreased renal function does not alter the single-dose pharmacokinetics of metronidazole.
Subjects with end-stage renal disease (ESRD; CL CR = 8.1±9.1 mL/min) and who received a single intravenous infusion of metronidazole 500 mg had no significant change in metronidazole pharmacokinetics but had 2-fold higher Cmax of hydroxy-metronidazole and 5-fold higher Cmax of metronidazole acetate, compared to healthy subjects with normal renal function (CL CR = 126±16 mL/min). Thus, on account of the potential accumulation of metronidazole metabolites in ESRD patients, monitoring for metronidazole associated adverse events is recommended (see PRECAUTIONS ).
Effect of Dialysis Following a single intravenous infusion or oral dose of metronidazole 500 mg, the clearance of metronidazole was investigated in ESRD subjects undergoing hemodialysis or continuous ambulatory peritoneal dialysis (CAPD). A hemodialysis session lasting for 4 to 8 hours removed 40% to 65% of the administered metronidazole dose, depending on the type of dialyzer membrane used and the duration of the dialysis session. If the administration of metronidazole cannot be separated from the dialysis session, supplementation of metronidazole dose following hemodialysis should be considered (see DOSAGE AND ADMINISTRATION ).
A peritoneal dialysis session lasting for 7.5 hours removed approximately 10% of the administered metronidazole dose. No adjustment in metronidazole dose is needed in ESRD patients undergoing CAPD. Hepatic Impairment Following a single intravenous infusion of 500 mg metronidazole, the mean AUC 24 of metronidazole was higher by 114% in patients with severe (Child-Pugh C) hepatic impairment, and by 54% and 53% in patients with mild (Child-Pugh A) and moderate (Child-Pugh B) hepatic impairment, respectively, compared to healthy control subjects.
There were no significant changes in the AUC 24 of hydroxyl-metronidazole in these hepatically impaired patients. A reduction in metronidazole dosage by 50% is recommended in patients with severe (Child-Pugh C) hepatic impairment (see DOSAGE AND ADMINISTRATION ). No dosage adjustment is…
📦 How Supplied / Storage and Handling ▾
HOW SUPPLIED 500 mg - White to off white, oblong shaped, biconvex, uncoated tablet, debossed with “HP65” on one side and plain on other side. NDC: 71335-1681-1: 20 Tablets in a BOTTLE NDC: 71335-1681-2: 30 Tablets in a BOTTLE NDC: 71335-1681-3: 14 Tablets in a BOTTLE NDC: 71335-1681-4: 56 Tablets in a BOTTLE NDC: 71335-1681-5: 21 Tablets in a BOTTLE NDC: 71335-1681-6: 4 Tablets in a BOTTLE NDC: 71335-1681-7: 28 Tablets in a BOTTLE NDC: 71335-1681-8: 100 Tablets in a BOTTLE NDC: 71335-1681-9: 60 Tablets in a BOTTLE NDC: 71335-1681-0: 40 Tablets in a BOTTLE Storage and Stability: Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].
Protect from light. Preserve in well closed light resistant container. Call your doctor for medical advice about side effects.
You may report side effects to FDA at 1-800-FDA-1088 or www.fda.gov/medwatch Repackaged/Relabeled by: Bryant Ranch Prepack, Inc. Burbank, CA 91504
📋 Description ▾
DESCRIPTION Metronidazole tablets USP, 250 mg or 500 mg is an oral formulation of the synthetic nitroimidazole antimicrobial, 2-methyl-5-nitro-1H-imidazole-1-ethanol, which has the following structural formula: Metronidazole tablets USP contain 250 mg or 500 mg of metronidazole. Inactive ingredients include colloidal silicon dioxide, crospovidone, hydrogenated vegetable oil, hydroxypropyl cellulose, microcrystalline cellulose.