Metrogel 0.75% Vaginal Gel 70gm
It is used to treat vaginal infections. If this drug has been given for some other reason, talk with the doctor for more information.
Drug Class
Anti-infective
Pharmacologic Class
Nitroimidazole antibiotic; Antiprotozoal
Pregnancy Category
Category B
FDA Approved
Jul 1992
DEA Schedule
Not Controlled
Overview
What is this medicine?
Metrogel is a gel that you put into your vagina to treat a common vaginal infection called bacterial vaginosis. It works by stopping the growth of the bacteria that cause the infection.
How to Use This Medicine
Proper Use of This Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Wash your hands before and after handling the medication. Continue using the medication as directed, even if your symptoms improve.
Important Administration Instructions
Do not take this medication by mouth. It is for vaginal use only. Avoid getting the medication in your mouth, nose, or eyes, as it may cause burning.
Some products are designed to be used at bedtime, while others can be used at any time. Consult with your pharmacist to determine the best time to use your specific product.
Duration of Use
Do not use this medication for longer than prescribed, as this may increase the risk of a second infection.
Storage and Disposal
Store the medication at room temperature, protecting it from heat and cold. Do not freeze the medication.
Missed Dose
If you miss a dose, use it as soon as you remember. However, if it is close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not use two doses at the same time or take extra doses.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Wash your hands before and after handling the medication. Continue using the medication as directed, even if your symptoms improve.
Important Administration Instructions
Do not take this medication by mouth. It is for vaginal use only. Avoid getting the medication in your mouth, nose, or eyes, as it may cause burning.
Some products are designed to be used at bedtime, while others can be used at any time. Consult with your pharmacist to determine the best time to use your specific product.
Duration of Use
Do not use this medication for longer than prescribed, as this may increase the risk of a second infection.
Storage and Disposal
Store the medication at room temperature, protecting it from heat and cold. Do not freeze the medication.
Missed Dose
If you miss a dose, use it as soon as you remember. However, if it is close to the time for your next dose, skip the missed dose and resume your regular schedule. Do not use two doses at the same time or take extra doses.
Lifestyle & Tips
- Avoid sexual intercourse during treatment to prevent reinfection and irritation.
- Avoid alcohol consumption during treatment and for at least 24-72 hours after the last dose to prevent a severe reaction (nausea, vomiting, flushing, headache).
- Complete the full course of treatment, even if symptoms improve, to ensure the infection is fully cleared.
- This medication may cause a metallic taste in your mouth.
- Do not use tampons during treatment; use sanitary pads if needed.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
One applicator full (approximately 5 grams containing 37.5 mg metronidazole) intravaginally once daily, preferably at bedtime, for 5 consecutive days.
Dose Range:
37.5 - 37.5 mg
Condition-Specific Dosing:
bacterialVaginosis:
One applicator full (approximately 5 grams containing 37.5 mg metronidazole) intravaginally once daily, preferably at bedtime, for 5 consecutive days.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Safety and efficacy not established in pediatric patients. Use in post-menarchal adolescents may be considered based on adult dosing if appropriate.
Dose Adjustments
Renal Impairment:
Mild:
No dosage adjustment necessary due to low systemic absorption.
Moderate:
No dosage adjustment necessary due to low systemic absorption.
Severe:
No dosage adjustment necessary due to low systemic absorption.
Dialysis:
No dosage adjustment necessary due to low systemic absorption. Systemic accumulation is unlikely.
Hepatic Impairment:
Mild:
No dosage adjustment necessary due to low systemic absorption.
Moderate:
No dosage adjustment necessary due to low systemic absorption.
Severe:
No dosage adjustment necessary due to low systemic absorption. Caution advised, but systemic exposure is minimal.
Pharmacology
Mechanism of Action
Metronidazole is a nitroimidazole antimicrobial. It enters the bacterial cell and is reduced by electron transport proteins to form reactive nitro radicals. These radicals damage bacterial DNA and other macromolecules, leading to cell death. It is active against a wide range of anaerobic bacteria and some protozoa.
Pharmacokinetics
Absorption:
Bioavailability:
Approximately 56% of the metronidazole absorbed systemically from a single 5-gram intravaginal dose (37.5 mg metronidazole) compared to a 500 mg oral dose. Peak plasma concentrations are significantly lower than with oral administration.
Tmax:
6-12 hours (for plasma concentrations after vaginal administration)
FoodEffect:
Not applicable for vaginal gel.
Distribution:
Vd:
Not directly applicable for vaginal gel due to low systemic absorption, but for systemic metronidazole, Vd is approximately 0.51-1.1 L/kg.
ProteinBinding:
Less than 20% (for systemic metronidazole)
CnssPenetration:
Limited (due to low systemic absorption from vaginal gel)
Elimination:
HalfLife:
6-11 hours (for systemic metronidazole, but plasma half-life after vaginal administration is similar to oral)
Clearance:
Not specifically quantified for vaginal gel due to low systemic absorption.
ExcretionRoute:
Mainly renal (60-80%), some fecal (6-15%)
Unchanged:
Approximately 20% (renal)
Pharmacodynamics
OnsetOfAction:
Clinical improvement typically seen within 2-3 days.
PeakEffect:
Not precisely defined for clinical effect, but peak plasma concentrations occur 6-12 hours post-dose.
DurationOfAction:
Effects persist throughout the 5-day treatment course and for a period after, leading to resolution of infection.
Confidence:
Medium
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
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
Irritation at the site where the medication was applied
Nervous system problems, including:
+ Burning, numbness, or tingling sensations that are not normal
+ Changes in balance or eyesight
+ Dizziness or fainting
+ Headache
+ Insomnia
+ Seizures
+ Speech difficulties
Emotional changes, such as:
+ Confusion
+ Depression
+ Irritability
+ Fatigue
+ Weakness
Vaginal discharge
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although 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 symptoms that bother you or do not go away, contact your doctor or seek medical help:
Headache
* Stomach pain
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. 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.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice any of the following symptoms, contact your doctor or seek immediate medical attention:
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
Irritation at the site where the medication was applied
Nervous system problems, including:
+ Burning, numbness, or tingling sensations that are not normal
+ Changes in balance or eyesight
+ Dizziness or fainting
+ Headache
+ Insomnia
+ Seizures
+ Speech difficulties
Emotional changes, such as:
+ Confusion
+ Depression
+ Irritability
+ Fatigue
+ Weakness
Vaginal discharge
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although 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 symptoms that bother you or do not go away, contact your doctor or seek medical help:
Headache
* Stomach pain
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. 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 abdominal pain
- Rash or hives
- Difficulty breathing or swelling of the face/throat (signs of allergic reaction)
- New or worsening vaginal itching or discharge (may indicate a yeast infection)
- Numbness or tingling in hands or feet (rare, but report if occurs)
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.
If you have taken disulfiram in the past 2 weeks, as this may interact with the medication.
If you are breastfeeding or plan to breastfeed, as this may require avoiding breastfeeding due to potential risks to the baby.
This medication may interact with other medications or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
Your health problems, including any medical conditions or diseases
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. They will help you determine if it is safe to take this medication with your other medications and health conditions.
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.
If you have taken disulfiram in the past 2 weeks, as this may interact with the medication.
If you are breastfeeding or plan to breastfeed, as this may require avoiding breastfeeding due to potential risks to the baby.
This medication may interact with other medications or health conditions. Therefore, it is crucial to provide your doctor and pharmacist with a comprehensive list of:
All prescription and over-the-counter (OTC) medications you are taking
Any natural products or vitamins you are using
Your health problems, including any medical conditions or diseases
Before starting, stopping, or changing the dose of any medication, including this one, you must consult with your doctor to ensure your safety. They will help you determine if it is safe to take this medication with your other medications and health conditions.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. Before consuming alcohol or using products containing alcohol, consult with your doctor, as you may need to avoid them during treatment and for a period after your last dose.
If you are using a product that contains propylene glycol, discuss this with your doctor. Long-term use of metronidazole has been associated with an increased risk of cancer in mice and rats; therefore, it is crucial to talk to your doctor about this potential risk.
This medication has been prescribed to treat a specific health condition. Do not use it for any other health problems without consulting your doctor. If you are pregnant or plan to become pregnant, inform your doctor to discuss the benefits and risks of using this medication during pregnancy.
While using this medication, refrain from having vaginal sex. Additionally, avoid douching or using other vaginal products, such as tampons, during treatment and for a period after your last dose. If you have any questions or concerns, consult with your doctor.
It is also important to note that this medication may interfere with certain laboratory tests. Ensure that your doctor and laboratory personnel are aware that you are taking this medication to avoid any potential interactions or inaccurate test results.
If you are using a product that contains propylene glycol, discuss this with your doctor. Long-term use of metronidazole has been associated with an increased risk of cancer in mice and rats; therefore, it is crucial to talk to your doctor about this potential risk.
This medication has been prescribed to treat a specific health condition. Do not use it for any other health problems without consulting your doctor. If you are pregnant or plan to become pregnant, inform your doctor to discuss the benefits and risks of using this medication during pregnancy.
While using this medication, refrain from having vaginal sex. Additionally, avoid douching or using other vaginal products, such as tampons, during treatment and for a period after your last dose. If you have any questions or concerns, consult with your doctor.
It is also important to note that this medication may interfere with certain laboratory tests. Ensure that your doctor and laboratory personnel are aware that you are taking this medication to avoid any potential interactions or inaccurate test results.
Overdose Information
Overdose Symptoms:
- Nausea
- Vomiting
- Ataxia (loss of coordination)
- Disorientation
- Seizures (rare)
What to Do:
Contact a poison control center immediately or seek emergency medical attention. Call 1-800-222-1222. Treatment is supportive and symptomatic.
Drug Interactions
Major Interactions
Moderate Interactions
- Lithium - Increased lithium levels (monitor lithium levels)
- Cimetidine - Decreased metronidazole clearance, increased metronidazole levels
- Phenobarbital, Phenytoin - Decreased metronidazole levels (due to enzyme induction)
- Busulfan - Increased busulfan toxicity (monitor busulfan levels)
- Fluorouracil - Increased fluorouracil toxicity
Confidence Interactions
Monitoring
Baseline Monitoring
Diagnosis of Bacterial Vaginosis
Rationale: Confirm appropriate indication for treatment.
Timing: Prior to initiation of therapy
Routine Monitoring
Clinical response (resolution of symptoms)
Frequency: Daily during treatment, and at follow-up visit
Target: Absence of vaginal discharge, odor, itching, and irritation
Action Threshold: Persistent or worsening symptoms may indicate treatment failure or alternative diagnosis.
Adverse effects (e.g., vulvovaginal candidiasis, GI upset)
Frequency: Daily during treatment
Target: Absence or mild, tolerable side effects
Action Threshold: Severe or persistent side effects may require discontinuation.
Symptom Monitoring
- Vaginal discharge (amount, color, odor)
- Vaginal itching or irritation
- Abdominal pain or cramping
- Nausea
- Headache
- Metallic taste in mouth
- Signs of candidiasis (e.g., thick, white, cottage-cheese like discharge, severe itching)
Special Patient Groups
Pregnancy
Metronidazole vaginal gel is considered Category B. Studies in animals have not shown harm to the fetus, and there are no adequate and well-controlled studies in pregnant women. Use during pregnancy should only be if clearly needed.
Trimester-Specific Risks:
First Trimester:
Generally avoided if possible, though data for vaginal gel suggest low systemic exposure and minimal risk. Oral metronidazole is often avoided in the first trimester unless benefits outweigh risks.
Second Trimester:
Considered safer than in the first trimester if treatment is necessary.
Third Trimester:
Considered safer than in the first trimester if treatment is necessary.
Lactation
Metronidazole is excreted into breast milk. While systemic absorption from vaginal gel is low, caution is advised. The American Academy of Pediatrics considers metronidazole compatible with breastfeeding. Consider temporary interruption of breastfeeding or use of an alternative drug if concerns exist.
Infant Risk:
Low risk of adverse effects in breastfed infants due to low systemic absorption from vaginal gel. Potential for metallic taste in milk, loose stools, or candidiasis in infant, but generally considered safe.
Pediatric Use
Safety and efficacy not established in pediatric patients. Use in post-menarchal adolescents may be considered based on adult dosing if appropriate and diagnosis is confirmed.
Geriatric Use
No specific dosage adjustments are necessary for elderly patients. Systemic exposure is low, and age-related changes in renal or hepatic function are unlikely to significantly impact drug levels from vaginal administration.
Clinical Information
Clinical Pearls
- Instruct patients on proper administration technique using the applicator.
- Emphasize the importance of completing the full 5-day course of therapy, even if symptoms improve earlier.
- Strongly advise patients to avoid alcohol during treatment and for at least 24-72 hours after the last dose due to the disulfiram-like reaction, despite low systemic absorption.
- Counsel patients that a metallic taste in the mouth is a common side effect.
- Warn patients about the potential for vulvovaginal candidiasis (yeast infection) as a superinfection, and to report new or worsening itching/discharge.
- Metronidazole vaginal gel is for vaginal use only and should not be taken orally.
Alternative Therapies
- Clindamycin vaginal cream (2% or ovules)
- Oral metronidazole
- Oral tinidazole
- Oral clindamycin
Cost & Coverage
Average Cost:
$50 - $150 per 70gm tube with applicators
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (for generic)
General Drug Facts
If your symptoms or health issues persist or worsen, it is essential to contact your doctor promptly. To ensure safe and effective treatment, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so it's a good idea to check with your pharmacist for more information. If you have any questions or concerns about this medication, don't hesitate to discuss them with 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 overdose, including the medication taken, the amount, and the time it occurred.