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metronidazole

Generic Name: metronidazole (me troe NI da zole)
Brand Name: Flagyl, Flagyl 375, Flagyl ER, ...show all 9 brand names

What is metronidazole?

Metronidazole is an antibiotic that fights bacteria.

Metronidazole is used to treat bacterial infections of the vagina, stomach, liver, skin, joints, brain, and respiratory tract. This medication will not treat a vaginal yeast infection.

Metronidazole may also be used for purposes not listed in this medication guide.

What is the most important information I should know about metronidazole?

You should not use metronidazole if you are allergic to it, or if you have taken disulfiram (Antabuse) within the past 2 weeks.

Do not drink alcohol or consume foods or medicines that contain propylene glycol while you are taking metronidazole and for at least 3 days after you stop taking it.

In animal studies, metronidazole caused certain types of cancers or tumors. It is not known whether these effects would occur in people using this medicine. Ask your doctor about your risk.

What should I discuss with my healthcare provider before taking metronidazole?

You should not take metronidazole if you are allergic to it, or if you have taken disulfiram (Antabuse) within the past 2 weeks.

To make sure metronidazole is safe for you, tell your doctor if you have ever had:

  • liver disease;

  • kidney disease;

  • a stomach or intestinal disease such as Crohn's disease;

  • a blood cell disorder such as anemia (lack of red blood cells) or low white blood cell (WBC) counts;

  • a fungal infection anywhere in your body; or

  • a nerve disorder.

In animal studies, metronidazole caused certain types of tumors, some of which were cancerous. However, very high doses are used in animal studies. It is not known whether these effects would occur in people using regular doses. Ask your doctor about your risk.

Using metronidazole during pregnancy could harm the unborn baby. Tell your doctor if you are pregnant or if you become pregnant while using this medicine.

Metronidazole can pass into breast milk and may harm a nursing baby. You should not breast-feed within 24 hours after using metronidazole. If you use a breast pump during this time, throw out any milk you collect. Do not feed it to your baby.

Do not give this medicine to a child without medical advice.

How should I take metronidazole?

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Shake the oral suspension (liquid) well just before you measure a dose. Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

If you are treating a vaginal infection, your sexual partner may also need to take metronidazole (even if no symptoms are present) or you could become reinfected.

Metronidazole is usually given for up to 10 days in a row. You may need to repeat this dosage several weeks later.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Metronidazole will not treat a viral infection such as the flu or a common cold.

Metronidazole can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using this medicine.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include nausea, vomiting, dizziness, loss of balance or coordination, numbness and tingling, or seizures (convulsions).

What should I avoid while taking metronidazole?

Do not drink alcohol or consume food or medicines that contain propylene glycol while you are taking metronidazole. You may have unpleasant side effects such as headaches, stomach cramps, nausea, vomiting, and flushing (warmth, redness, or tingly feeling). Also avoid alcohol or propylene glycol for at least 3 days after you stop taking metronidazole.

Check the labels of any medicines or food products you use to make sure they do not contain alcohol or propylene glycol

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Metronidazole side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • severe stomach pain, diarrhea that is watery or bloody;

  • trouble sleeping, depression, feeling irritable;

  • headache, dizziness, weakness;

  • a light-headed feeling (like you might pass out); or

  • blisters or ulcers in your mouth, red or swollen gums, trouble swallowing.

Stop taking the medicine and call your doctor right away if you have neurologic side effects (more likely to occur while taking metronidazole long term):

  • numbness, tingling, or burning pain in your hands or feet;

  • vision problems, pain behind your eyes, seeing flashes of light;

  • muscle weakness, problems with coordination;

  • trouble speaking or understanding what is said to you;

  • a seizure; or

  • fever, neck stiffness, and increased sensitivity to light.

Side effects may be more likely in older adults.

Common side effects may include:

  • nausea, vomiting, loss of appetite, stomach pain;

  • diarrhea, constipation;

  • unpleasant metallic taste;

  • rash, itching;

  • vaginal itching or discharge;

  • mouth sores; or

  • swollen, red, or "hairy" tongue.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Side Effects (complete list)

Metronidazole dosing information

Usual Adult Dose for Bacterial Infection:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release Capsules and Tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Uses: For the treatment of serious infections due to susceptible anaerobic bacteria including:
-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
-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

Infectious Diseases Society of America (IDSA) recommendations:
Surgical Site Infections: 500 mg IV every 8 hours in combination with ceftriaxone, ciprofloxacin, or levofloxacin

Uses: For the treatment of infections following operations on the axilla, gastrointestinal tract, perineum, or female genital tract

Usual Adult Dose for Amebiasis:

Acute Intestinal Amebiasis (Acute Amebic Dysentery):
-Immediate-release capsules and tablets: 750 mg orally 3 times a day for 5 to 10 days

Amebic Liver Abscess:
-Immediate-release capsules and tablets: 500 to 750 mg orally 3 times a day for 5 to 10 days

Comments: Aspiration or drainage of pus is still needed for amebic liver abscess.

Use: For the treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess

Usual Adult Dose for Pseudomembranous Colitis:

IDSA and Society for Healthcare Epidemiology of America (SHEA) recommendations:
Mild to moderate Clostridium difficile infection (CDI) initial episode:
-Immediate release tablets: 500 mg orally 3 times a day for 10 to 14 days

Severe, complicated CDI: 500 mg IV every 8 hours with oral vancomycin

Comments:
-Metronidazole is the drug of choice for initial episode of mild to moderate CDI.
-Vancomycin orally (or rectally if ileus is present) with or without IV metronidazole is the regimen of choice for initial episode of severe, complicated CDI.
-Metronidazole should not be used beyond the first recurrence of CDI or for long-term chronic therapy due to possible neurotoxicity.

Usual Adult Dose for Surgical Prophylaxis:

Initial preoperative dose: 15 mg/kg IV infused over 30 to 60 minutes and completed about 1 hour before surgery
Following initial dose: 7.5 mg/kg IV infused over 30 to 60 minutes at 6 and 12 hours after the initial dose

Comments:
-Should be administered, if needed, at 6-hour intervals to maintain effective drug levels
-Prophylactic use should be limited to the day of surgery, following the above guidelines.

Use: For surgical prophylaxis to prevent postoperative infection in contaminated or potentially contaminated colorectal surgery

IDSA, SHEA, American Society of Health-System Pharmacists (ASHP), and Surgical Infection Society (SIS) recommendations:
-IV: 500 mg IV 1 hour before surgery; duration of prophylaxis for all procedures should be less than 24 hours

Colorectal Surgery Prophylaxis:
-Oral: 1 g orally in 3 divided doses over about 10 hours beginning after the mechanical bowl preparation the afternoon or evening before the procedure

Comments:
-May be used in combination with other antibiotics.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Trichomoniasis:

Immediate-release Capsules: 375 mg orally twice a day for 7 consecutive days

Immediate-release Tablets:
-One-day regimen: 2 g orally as a single dose or 1 g twice given in the same day
-Seven-day regimen: 250 mg orally 3 times a day for 7 consecutive days

Comments:
-Single-dose regimens can assure compliance, however, a 7-day course may minimize reinfection by protecting the patient long enough for the sexual contact to be treated.
-The dose regimen should be individualized in females and males; some patients may tolerate 1 regimen more than the other.
-The patient's sexual partner(s) should also be evaluated/treated.
-If repeat courses are required, an interval of 4 to 6 weeks should elapse between courses and the presence of the trichomonad be reconfirmed by appropriate laboratory testing.
-Pregnant patients should not be treated during the first trimester; if alternative therapy was not adequate in a pregnant patient, the 1-day regimen is not recommended (results in higher serum levels which can reach fetal circulation).

Uses:
-Symptomatic trichomoniasis: For the treatment of Trichomonas vaginalis infection in females and males when confirmed by appropriate laboratory procedures (wet smears and/or cultures)
-Asymptomatic trichomoniasis: For the treatment of asymptomatic T vaginalis infection in females when associated with endocervicitis, cervicitis, or cervical erosion
-Treatment of asymptomatic sexual partners: For the simultaneous treatment of asymptomatic sexual partners of treated patients if T vaginalis is present to prevent reinfection of the partner

US CDC recommendations:
Immediate-release Tablets:
-Recommended regimen: 2 g orally as a single dose
-Alternative regimen: 500 mg orally twice a day for 7 days

Trichomoniasis in HIV-infected women:
-Immediate-release tablets: 500 mg orally twice a day for 7 days

Treatment failure with single-dose therapy and reinfection is excluded:
-Immediate-release tablets: 500 mg orally twice a day for 7 days; for patients failing this regimen, 2 g orally once a day for 7 days should be considered

Comments:
-Sexual partner(s) should be treated simultaneously with the same dose; appropriate treatment of sexual partner(s) may increase reported cure rates.
-Women can be treated with 2 g orally as a single dose at any stage of pregnancy.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Helicobacter pylori Infection:

Some experts recommend:
Bismuth quadruple therapy: 250 mg orally 4 times a day
Clarithromycin-based triple therapy: 500 mg orally twice a day
Duration of therapy: 10 to 14 days

Comments:
-Bismuth quadruple therapy is one recommended primary therapy; includes (a proton pump inhibitor [PPI] or histamine-2 receptor antagonist), bismuth, metronidazole, and tetracycline.
-Clarithromycin-based triple therapy is another recommended primary therapy; includes a PPI, clarithromycin, and (amoxicillin or metronidazole).

Usual Adult Dose for Pelvic Inflammatory Disease:

US CDC recommendations:
Mild to moderately severe acute pelvic inflammatory disease (PID):
-Immediate-release tablets: 500 mg orally twice a day for 14 days

Comments:
-Recommended regimens for outpatient, oral therapy include ceftriaxone plus doxycycline with or without metronidazole, cefoxitin/probenecid plus doxycycline with or without metronidazole, or other parenteral third-generation cephalosporin plus doxycycline with or without metronidazole.
-Since anaerobic organisms are suspected in the etiology of PID, the addition of metronidazole should be considered; also effectively treats bacterial vaginosis, which is often associated with PID.
-When tuboovarian abscess is present, metronidazole with doxycycline is recommended for continued therapy; provides more effective anaerobic coverage than doxycycline alone.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Bacterial Vaginosis:

Extended-release Tablets: 750 mg orally once a day for 7 consecutive days

Comments: Should be taken under fasting conditions at least 1 hour before or 2 hours after meals.

Use: For the treatment of bacterial vaginosis in non-pregnant women

US CDC recommendations:
-Immediate-release tablets: 500 mg orally twice a day for 7 days

Comments:
-Treatment is recommended for all women with symptoms.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Intraabdominal Infection:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release capsules and tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Uses: For the treatment of intraabdominal infections, including 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

IDSA and SIS recommendations:
-Immediate-release tablets: 500 mg IV every 8 to 12 hours or 1500 mg IV every 24 hours

Use: For empiric treatment of complicated intraabdominal infection

Usual Adult Dose for Peritonitis:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release capsules and tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Uses: For the treatment of intraabdominal infections, including 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

IDSA and SIS recommendations:
-Immediate-release tablets: 500 mg IV every 8 to 12 hours or 1500 mg IV every 24 hours

Use: For empiric treatment of complicated intraabdominal infection

Usual Adult Dose for Liver Abscess:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release capsules and tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Uses: For the treatment of intraabdominal infections, including 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

IDSA and SIS recommendations:
-Immediate-release tablets: 500 mg IV every 8 to 12 hours or 1500 mg IV every 24 hours

Use: For empiric treatment of complicated intraabdominal infection

Usual Adult Dose for Joint Infection:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release capsules and tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Uses: As adjunctive therapy for the treatment of bone and joint infections caused by Bacteroides species including B fragilis group

IDSA recommendations:
Native Vertebral Osteomyelitis (NVO): 500 mg orally 3 to 4 times a day

Comments:
-Can be used in the initial course of NVO due to Bacteroides species and other susceptible anaerobes.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Osteomyelitis:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release capsules and tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Uses: As adjunctive therapy for the treatment of bone and joint infections caused by Bacteroides species including B fragilis group

IDSA recommendations:
Native Vertebral Osteomyelitis (NVO): 500 mg orally 3 to 4 times a day

Comments:
-Can be used in the initial course of NVO due to Bacteroides species and other susceptible anaerobes.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Skin or Soft Tissue Infection:

IV:
-Loading dose: 15 mg/kg IV once infused over 1 hour
-Maintenance dose: 7.5 mg/kg IV infused over 1 hour every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

ORAL:
Immediate-release capsules and tablets: 7.5 mg/kg orally every 6 hours
-Maximum dose: 4 g per day
-Duration of therapy: 7 to 10 days

Comments:
-The first IV maintenance dose should be started 6 hours after the start of the loading dose.
-IV therapy may be changed to oral when conditions warrant, based upon severity of disease and response of the patient.
-Infections of the bone and joint, lower respiratory tract, and endocardium may require longer treatment.

Use: Skin and skin structure infections caused by Bacteroides species including the B fragilis group, Clostridium species, Peptococcus species, Peptostreptococcus species, and Fusobacterium species

IDSA recommendations:
Necrotizing infection: 500 mg IV every 6 hours in combination with cefotaxime

Comments:
-Antimicrobial therapy should be continued until further debridement is no longer needed, the patient has improved clinically, and fever has been absent for 48 to 72 hours.
-Current guidelines should be consulted for additional information.

Use: For the treatment of necrotizing infections of the skin, fascia, and muscle

Usual Adult Dose for Giardiasis:

Some experts recommend: 250 mg orally 3 times a day for 5 to 7 days

Usual Adult Dose for STD Prophylaxis:

US CDC recommendations:
-Immediate-release tablets: 2 g orally once as a single dose in combination with ceftriaxone and azithromycin

Use: For sexually transmitted disease (STD) prophylaxis following sexual assault or abuse

Usual Adult Dose for Nongonococcal Urethritis:

US CDC recommendations:
Recurrent or persistent urethritis:
-Immediate-release tablets: 2 g orally once as a single dose

Comments:
-Use should be reserved for recurrent or persistent urethritis in men who have sex with women in areas where T vaginalis is prevalent.
-Sexual partners should be referred for evaluation and appropriate treatment.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Balantidium coli:

US CDC recommendations:
-Immediate-release tablets: 500 to 750 mg orally 3 times a day for 5 days

Usual Adult Dose for Dientamoeba fragilis:

US CDC recommendations:
-Immediate-release tablets: 500 to 750 mg orally 3 times a day for 10 days

Usual Adult Dose for Wound Infection:

IDSA recommendations:
-Oral: 250 to 500 mg orally 3 times a day
-IV: 500 mg IV every 8 hours

Comments:
-May be used in combination with other antibiotics.
-Current guidelines should be consulted for additional information.

Uses: For the treatment of infections following animal or human bites

Usual Pediatric Dose for Bacterial Infection:

American Academy of Pediatrics (AAP) recommendations:
Neonates:
7 days or less:
-Up to 2 kg: 7.5 mg/kg IV every 12 hours
-Greater than 2 kg: 7.5 mg/kg IV every 8 hours
8 to 28 days:
-Up to 2 kg: 7.5 mg/kg IV every 12 hours
-Greater than 2 kg: 7.5 mg/kg IV every 6 hours

Postmenstrual age less than 34 weeks: 7.5 mg/kg IV every 12 hours
Postmenstrual age 34 to 40 weeks: 7.5 mg/kg IV every 8 hours
Postmenstrual age greater than 40 weeks: 7.5 mg/kg IV every 6 hours

Comments:
-All categories (for body weight 2 kg or less and greater than 2 kg; for 7 days or less and 8 to 28 days of age; and all categories of postmenstrual age) should receive a loading dose of 15 mg/kg IV once.
-The longer dosing interval may be used in extremely low birth weight (less than 1 kg) neonates until 2 weeks of life.
-Current guidelines should be consulted for additional information.

1 month or older:
IV: 22.5 to 40 mg/kg/day IV in 3 divided doses
Maximum dose: 1.5 g/day

Oral: 30 to 50 mg/kg/day orally in 3 divided doses
Maximum dose: 2.25 g/day

Usual Pediatric Dose for Amebiasis:

Immediate release capsules and tablets: 35 to 50 mg/kg/day orally in 3 divided doses for 10 days

Comments: Aspiration or drainage of pus is still needed for amebic liver abscess.

Use: For the treatment of acute intestinal amebiasis (amebic dysentery) and amebic liver abscess

Usual Pediatric Dose for Pseudomembranous Colitis:

AAP recommendations.
1 month or older: 30 mg/kg/day orally in 4 divided doses
Maximum dose: 2 g/day
Duration of therapy: At least 10 days

Comments:
-Antimicrobial therapy for C difficile infection is recommended for symptomatic patients.
-Metronidazole is the drug of choice for initial treatment of mild to moderate diarrhea and for first relapse.
-Vancomycin enema plus IV metronidazole is recommended as initial therapy for patients with severe disease and for patients who do not respond to oral metronidazole.
-Metronidazole should not be used beyond the first recurrence or for chronic therapy due to possible neurotoxicity.
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Trichomoniasis:

AAP recommendations:
Children less than 45 kg: 45 mg/kg/day orally in 3 divided doses for 7 days
-Maximum dose: 2 g per day

Adolescent vulvovaginitis: 2 g orally once as a single dose

Comments:
-The patient's sexual partner(s) should be treated simultaneously.
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Bacterial Vaginosis:

AAP recommendations:
Children less than 45 kg: 45 mg/kg/day orally in 3 divided doses for 7 days
-Maximum dose: 2 g per day

Adolescent vulvovaginitis: 500 mg orally twice a day for 7 days

Comments:
-All women with symptoms should be treated.
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Giardiasis:

Some experts recommend: 15 mg/kg/day orally in 3 divided doses for 5 to 7 days
-Maximum dose: 250 mg/dose

Usual Pediatric Dose for STD Prophylaxis:

US CDC recommendations:
-Adolescents: 2 g orally once as a single dose in combination with ceftriaxone and azithromycin

Use: For sexually transmitted disease (STD) prophylaxis following sexual assault or abuse

Usual Pediatric Dose for Balantidium coli:

AAP recommendations: 35 to 50 mg/kg/day orally in 3 divided doses for 5 days
-Maximum dose: 750 mg/dose

Usual Pediatric Dose for Dientamoeba fragilis:

AAP recommendations: 35 to 50 mg/kg/day orally in 3 divided doses for 10 days
-Maximum dose: 750 mg/dose

Usual Pediatric Dose for Pelvic Inflammatory Disease:

US CDC recommendations:
Adolescents:
Mild to moderately severe acute pelvic inflammatory disease (PID):
-Immediate-release tablets: 500 mg orally twice a day for 14 days

Comments:
-Recommended regimens for outpatient, oral therapy include ceftriaxone plus doxycycline with or without metronidazole, cefoxitin/probenecid plus doxycycline with or without metronidazole, or other parenteral third-generation cephalosporin plus doxycycline with or without metronidazole.
-Since anaerobic organisms are suspected in the etiology of PID, the addition of metronidazole should be considered; also effectively treats bacterial vaginosis, which is often associated with PID.
-When tuboovarian abscess is present, metronidazole with doxycycline is recommended for continued therapy; provides more effective anaerobic coverage than doxycycline alone.
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Surgical Prophylaxis:

IDSA, SHEA, ASHP, and SIS recommendations:
Less than 1 month:
-Less than 1.2 kg: 7.5 mg/kg IV once
-Greater than or equal to 1.2 kg: 15 mg/kg IV once

1 month or older: 15 mg/kg IV once

Comments:
-The maximum pediatric doses should not exceed the usual adult dose of 500 mg.
-Duration of prophylaxis for all procedures should be less than 24 hours.
-Current guidelines should be consulted for additional information.

Colorectal Surgery Prophylaxis:
1 year or older:
-Oral: 15 mg/kg orally in 3 divided doses over about 10 hours beginning after the mechanical bowl preparation the afternoon or evening before the procedure

What other drugs will affect metronidazole?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you take, which may increase side effects or make the medications less effective.

Tell your doctor about all your current medicines and any you start or stop using, especially:

  • busulfan;

  • lithium; or

  • a blood thinner--warfarin, Coumadin, Jantoven.

This list is not complete. Other drugs may interact with metronidazole, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about metronidazole.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 11.02.

Last reviewed: October 04, 2017
Date modified: December 03, 2017

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