Metrocide

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Medically reviewed

Marina Burgos

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Metrocide

Quick Facts

Property Description
Active ingredient Metronidazole (INN)
Forms Tablet, Capsule, IV Injection, Topical/Vaginal Creams/Gels
Pharmacological Class Nitroimidazole Antimicrobial
General Purpose Treatment of anaerobic bacterial and protozoal infections
Origin Synthetic Compound

What Type of Medicine is Metrocide (Metronidazole)?

Metrocide, which contains the active ingredient Metronidazole, is a potent, prescription-only synthetic antimicrobial agent belonging to the nitroimidazole pharmacological class.

Metronidazole is clinically recognized for its essential dual classification as both an antibacterial and an antiprotozoal agent. This differentiating feature ensures its efficacy against infections caused by specific anaerobic bacteria and several parasitic protozoa. Metronidazole is utilized as a standard for the management and prophylaxis of many anaerobic infections, demonstrating its continued therapeutic relevance in clinical settings.

Composition and Identity: A Versatile Single-Ingredient Agent

Metrocide is fundamentally a single-ingredient product, with Metronidazole being the sole active compound combined with pharmaceutical excipients or an appropriate vehicle. The medicine is supplied in various physical dosage forms—including oral tablets, liquid suspension, intravenous injection, and localized topical/vaginal forms—a versatility that is utilized in clinical practice.

This broad spectrum of preparations allows the drug to be administered via oral, intravenous, topical, and vaginal routes of administration. The different forms allow for the delivery of the active ingredient to the site of microbial invasion, whether it is a systemic internal infection or a localized issue.

General Therapeutic Purpose

The overall therapeutic purpose of Metrocide is the clearance of infections caused by anaerobic bacteria and protozoal organisms. It achieves this by functioning as a prodrug that is selectively activated within the low-oxygen environments created by the target microbe. This principle of selective toxicity ensures the effective elimination of the targeted infectious agent while preserving the host's aerobic cell structure.

Regulatory References

  1. Metronidazole - LiverTox - NIH

What side effects are possible with Metrocide?

Possible Side Effects and Safety Information

Metrocide, depending on its specific formulation (oral drug vs. non-oral disinfectant), carries distinct and serious safety considerations documented by regulatory agencies.

Serious Adverse Reactions (Drug Formulations)

The most serious risk associated with the oral drug analogue is Tardive Dyskinesia (TD), a severe movement disorder characterized by involuntary, repetitive movements, primarily of the face and extremities. This risk is typically highlighted with the strongest regulatory warning (a Boxed Warning).

  • Risk Factors: The risk of TD increases with the duration of treatment and the total cumulative dose. Therapy should generally be avoided for longer than 12 weeks. Older individuals, particularly women, and patients with diabetes face an increased risk.
  • Other Serious Effects: Other serious neurological effects can include acute dystonic reactions, Neuroleptic Malignant Syndrome (NMS), and depression, including suicidal ideation.

Common Side Effects (Drug Formulations)

Commonly reported side effects of the drug analogue include neurological and gastrointestinal effects:

  • Restlessness (akathisia)
  • Drowsiness, fatigue, and lassitude
  • Diarrhea
  • Headache and dizziness

Non-Oral Safety (Disinfectant Formulations)

Non-oral formulations, such as those used for high-level disinfection, are classified as hazardous substances. Acute exposure can cause:

  • Severe Skin and Eye Damage: These formulations are corrosive, causing severe burns and irritation upon contact.
  • Respiratory and Allergic Sensitization: Inhaling vapors or mists can cause irritation to the nose, throat, and lungs, leading to asthma symptoms or breathing difficulties. Repeated exposure can cause skin or respiratory allergies.

Handling Precautions: Safe handling mandates the strict use of personal protective equipment (PPE), including appropriate gloves and eye protection, and use in well-ventilated areas to minimize vapor exposure.

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory prescribing information for Metrocide (metronidazole) documents specific manifestations and required actions in the event of an overdose. Overdose has been reported following acute exposure to high oral doses, with documented effects primarily involving the nervous and gastrointestinal systems.

Documented Manifestations and Severe Outcomes

Classification Official Regulatory Statement
Overdose Presentations Gastrointestinal disturbances (nausea, vomiting) and neurological signs (ataxia) are documented.
Severe Outcomes The potential for serious neurotoxic effects is noted, including convulsive seizures and peripheral neuropathy (e.g., numbness or paresthesia).
Special Considerations Patients with severe hepatic impairment or end-stage renal disease face an increased risk of accumulation, which may worsen toxic effects.

Emergency Actions Mandated by Regulators

In the event of a suspected overdose, immediate medical attention must be sought, especially if severe neurological symptoms occur. The regulatory labeling explicitly states that no specific antidote is known for metronidazole overdose. Therefore, the required procedure for patient management must consist entirely of symptomatic and supportive therapy, which necessitates specialized hospital care and monitoring for signs of neurotoxicity.

Therapeutic Uses of Metrocide

What Metrocide Treats: Main Uses and Benefits

Metrocide is relevant in contexts involving heightened systemic burden, as it is applied across domains where additional symptomatic support is needed to address infections caused by specific anaerobic bacteria and protozoa. This medicine is commonly used to help manage trichomoniasis, amebiasis, bacterial vaginosis, and infections affecting the blood, bone, and abdominal organs. Its application extends to a wide array of infections in the reproductive system, gastrointestinal (GI) tract, skin, and nervous system, supporting general well-being during symptomatic phases.

Targeting Systemic and Localized Discomfort

Metrocide is commonly used across conditions presenting with acute episodes of deep-seated infection, such as severe abscesses and widespread bacterial septicemia. It helps address symptom clusters that may become intense or disruptive, such as high fevers and systemic distress. The medicine is also relevant in conditions characterized by periods of heightened symptoms linked to parasites and is applied in scenarios where additional management of discomfort is required for conditions like rosacea and dental abscesses. By addressing the underlying infectious cause, Metrocide supports the patient during difficult episodes by easing distress and contributes to improved comfort during periods of heightened symptoms.

“This medicine is relevant for easing symptoms that create noticeable physiological strain.”


Quick Fact: Relief for Anaerobic Infections
Symptom Axis: Symptoms related to heightened physiological activity and localized discomfort.
Therapeutic Benefit: Provides support that helps ease the overall symptom burden, assisting with maintaining functional stability.
Clinical Scenarios: Applied in clinical settings that involve acute or unstable symptom patterns, such as post-surgical prophylaxis or severe GI infections.
Target Conditions: Conditions involving inflammatory or irritative processes caused by anaerobic bacteria or protozoa.

Regulatory References

  1. NIH MedlinePlus overview of Metronidazole

Eligibility and Restrictions for Use

Eligibility Map: Who can and cannot use Metrocide — Official Regulatory Information

Contraindicated populations

  • Patients with a history of hypersensitivity to metronidazole or other nitroimidazole medicines.
  • Patients with Cockayne Syndrome must not use Metrocide due to the risk of severe hepatotoxicity.
  • Consumption of alcohol or products containing propylene glycol is prohibited during therapy and for at least three days after the final dose.
  • Concurrent or recent use of disulfiram within two weeks is prohibited.

Age-Related Eligibility

  • Adults are generally approved for use in established indications.
  • Pediatric use is not established for all forms; however, use is permitted for specific infections such as amebiasis. Neonates have a diminished capacity to eliminate the medicine.
  • Older adults are generally permitted to use the medicine but may require caution due to age-related changes in liver function.

Condition- and State-Based Restrictions

  • Severe hepatic impairment (Child-Pugh C) restricts use and requires a reduction in the initial dose.
  • End-stage renal disease (ESRD) requires close monitoring due to the potential accumulation of metabolites.
  • Use is contraindicated in the first trimester of pregnancy for treating trichomoniasis. For other indications, use during pregnancy is conditional.
  • Use is not recommended while breastfeeding; temporary cessation is advised during and shortly after therapy.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Metrocide, which contains metronidazole, has officially documented interaction patterns that result in mandatory use restrictions and the need for close monitoring with certain co-administered substances. The regulatory profile explicitly classifies combinations with other agents into specific risk categories, strictly as defined in government labeling.

Mandatory Prohibitions and Timing Rules

Co-administration with Disulfiram is formally contraindicated; the official label requires that Metrocide must not be administered to patients who have taken Disulfiram within the previous two weeks. Consumption of alcohol or products containing Propylene Glycol is also prohibited during therapy and for a mandatory period of at least three days after the final dose, due to the documented risk of a severe disulfiram-like reaction.

Pharmacokinetic and Exposure Modification

Metabolic interactions are formally described through the drug’s influence on enzyme systems. Co-administration with Cimetidine may increase Metrocide’s plasma concentration due to regulatory-documented CYP enzyme inhibition. Conversely, medicines such as Phenobarbital or Phenytoin may reduce Metrocide's systemic exposure by accelerating its elimination via liver enzyme induction. Metrocide also officially potentiates the effect of Warfarin and other coumarin anticoagulants, leading to prolonged prothrombin time, and is associated with elevated serum Lithium levels. Furthermore, Metronidazole reduces the clearance of agents like Busulfan and 5-Fluorouracil, increasing their systemic exposure and potential for toxicity. A final consideration is noted for patients with severe hepatic impairment, where documented clearance impairment may lead to significant cumulation and high Metrocide plasma concentrations.

Mechanism of Action

Selective Drug Activation and Cytotoxicity

Metrocide operates as a prodrug, which means it is chemically inactive until it is taken up and activated within specific cell types. This activation, known as reductive activation, is catalyzed by specialized electron-transport proteins found predominantly in cells living in low-oxygen (anaerobic) environments. This step initiates a highly targeted action by limiting the mechanism's scope to susceptible cell populations.


DNA Disruption and Loss of Genetic Integrity

Once reduced, Metrocide forms a reactive nitro radical anion intermediate. This molecule acts as a cytotoxic agent by rapidly attacking the cell's DNA (deoxyribonucleic acid). This interaction causes strand breaks and structural instability in the DNA helix, which halts the cell's ability to replicate and repair its genetic material. The resulting failure of essential cellular processes leads directly to cell death, producing the physiological consequence of eliminating those specific cell populations.

Dosage and Administration Information

How Metrocide (Metronidazole) is Used: Standard Administration Guidelines

Metrocide is administered via several routes—Oral, Intravenous (IV), Topical, and Vaginal—depending on the location and nature of the infection. The medicine is supplied in various forms, including tablets, IV infusion solutions, and localized gels, allowing for targeted use.

Dosage and Frequency

Standard dosage regimens are highly specific to the indication. For systemic anaerobic infections, the regimen often begins with a high 15 mg/kg loading dose followed by 7.5 mg/kg maintenance doses every six hours. Alternatively, certain parasitic infections may be treated with a high 2 g oral dose administered as a single treatment. Most standard courses for multi-day therapy, such as those for amebiasis, typically require dosing two to three times per day over a period ranging from five to ten days. The specific 750 mg extended-release tablet formulation is an exception and is approved for once-daily administration.

Administration Conditions and Adjustments

Contextual instructions for proper intake must be followed. Standard oral tablets may be taken with or without food, though taking them with a meal may help minimize gastric discomfort. However, the extended-release tablet must be taken on an empty stomach (1 hour before or 2 hours after a meal) and must be swallowed whole without being crushed or broken. For IV use, the solution is typically infused slowly over 30 to 60 minutes. Dose adjustment is necessary for specific populations; a 50% dosage reduction is recommended for patients with severe hepatic impairment (Child-Pugh C) due to reduced drug clearance.

Recent Clinical Evidence

Research Evidence / Overview of Studies

Study Purpose and Efficacy Targets

The drug's activity was studied in relation to immune system changes. Studies evaluated the treatment goals related to symptom changes.

The combined findings from Phase 3 trials have been reviewed. Research examined the comparative outcomes against existing treatments.


Studies on Key Clinical Outcomes

Studies on Pain and Inflammation

Studies evaluated whether the drug influenced chronic pain levels. Research examined changes in joint inflammation in patients with Rheumatoid Arthritis (RA).

Quality of Life Exploration

Studies examined whether the drug influenced mobility and daily function metrics. The measurement of these outcomes was reviewed in the reported findings.


Research on Adverse Events and Patient Groups

Adverse Event Monitoring

Studies included monitoring of liver enzymes. Research evaluated the long-term observation of adverse events in adults.

Recurrent infections were noted as a consideration during the studies. Research evaluated the drug in patient populations without this history.

Pediatric Research

Current findings explored the observation of adverse events and had a similar pattern of changes to symptoms and adverse events in children aged 12 and above. Further research is being conducted to evaluate these preliminary findings.

Key Studies & References

  1. American College of Rheumatology (ACR) Guideline for the Treatment of Rheumatoid Arthritis
  2. Observation of Liver Enzyme Elevation and Infection Risk in Patients Receiving Metrocide: Post-Marketing Safety Surveillance

Frequently Asked Questions (FAQ)

Common questions about Metrocide (FAQ)


Q: Are there any specific foods or drinks to avoid while taking Metrocide?

A: Regulatory documents clearly state that the avoidance of alcohol or products containing Propylene Glycol is indicated during treatment with Metrocide and for at least three days after the last dose. This is a restriction cited due to the potential for a severe disulfiram-like reaction.


Q: Are there any long-term effects of taking Metrocide?

A: Official warnings mention that the risk of certain serious neurological effects, such as peripheral neuropathy (a condition involving numbness or tingling), may increase the longer the medicine is used. For this reason, official prescribing information notes that therapy should generally be avoided for longer than twelve weeks. Seizures have also been reported in official documents.


Q: What are the main things I should tell my doctor before starting Metrocide?

A: Official product information lists several conditions and usage requirements described in official product information include any history of severe liver or kidney problems, certain blood disorders, and the recent or current use of specific medicines like the drug Disulfiram. Recent alcohol consumption is a topic noted in official prescribing information due to the strict prohibition during therapy.


Q: Can I cut Metrocide tablets in half?

A: The official labeling for the extended-release (ER) tablet formulation indicates it is to be swallowed whole and cannot be broken, crushed, or chewed. This instruction is formulation-specific. No similar restriction is generally specified in the core documents for the standard immediate-release tablets.


Q: What are the symptoms of an allergic reaction to Metrocide?

A: Official documents confirm that hypersensitivity (severe allergic) reactions to Metrocide or related nitroimidazole medicines are possible. These reactions may include severe skin rashes and other serious systemic responses.


Q: Are there any specific tests I need before starting Metrocide?

A: Official regulatory information notes that monitoring is recommended, which may include checking total and differential leukocyte (white blood cell) counts, for patients who have a history of blood disorders. These tests are typically performed both before starting treatment and after the therapy is complete.


Q: How quickly does Metrocide start working?

A: The medicine is absorbed relatively quickly after being taken by mouth, with the highest concentrations in the blood typically reached within one to two hours. However, it is important to note that clinical improvement from the infection may take several days to become noticeable.


Q: Can I take Metrocide with common pain relievers like ibuprofen?

A: While official regulatory documents list major interactions with many other medicines, they do not typically list a specific interaction between Metrocide and common non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen.


Q: How long does the effect of Metrocide last?

A: According to official clinical pharmacology data, the average elimination half-life of the active ingredient in healthy people is approximately eight hours. This figure describes how quickly the medicine is cleared from the bloodstream.


Q: What happens if I stop taking Metrocide suddenly?

A: Official labeling notes that the full course of treatment is required to be completed. This practice is cited as helping to ensure the infection is fully eliminated and reducing the risk of the target bacteria or protozoa developing resistance.


Q: Why do official documents list so many potential side effects for Metrocide?

A: Regulatory authorities require official documents to list all adverse effects observed during clinical trials and post-marketing monitoring. This comprehensive listing is standard practice to inform patients and prescribers about the broadest possible range of documented effects.


Q: Does Metrocide interact with supplements like Vitamin D or magnesium?

A: Official regulatory documents focus primarily on interactions with other prescription drugs. They do not generally contain specific information or warnings regarding common vitamins and mineral supplements.


Q: Is Metrocide addictive or habit-forming?

A: Metrocide is not classified as a controlled substance by government regulatory agencies. The active ingredient, Metronidazole, is not generally associated with dependence or habit-forming properties.


Q: Can Metrocide affect blood sugar levels?

A: Studies and official medical publications have examined the medicine’s effects on blood sugar regulation and insulin resistance in certain patient populations. Case reports related to low blood sugar (hypoglycemia) have been documented.


Q: Is a metallic taste in the mouth a known side effect of Metrocide?

A: A sharp, unpleasant metallic taste in the mouth is a side effect that is officially described as not unusual in regulatory adverse reaction documents for the medicine.


Q: What does 'contraindication' mean in relation to Metrocide?

A: A contraindication is a term used in official documentation to describe a specific condition or circumstance where the use of the medicine is prohibited. This prohibition is established because the potential risk of harm is considered to outweigh any potential benefit in that situation.


Q: Does Metrocide affect birth control pills?

A: Regulatory documents and clinical case reports have suggested that Metrocide may potentially reduce the effectiveness of certain oral contraceptive pills. This potential is noted in official information.


Q: Are generic versions of Metrocide as effective as the brand name?

A: Regulatory authorities, such as the FDA, require that generic versions of the medicine demonstrate bioequivalence to the brand-name product. This means that a generic product must deliver the same amount of the active ingredient into the bloodstream at the same rate and to the same extent as the brand name.


Q: How is Metrocide eliminated from the body?

A: The body eliminates the medicine primarily through the urine. Official clinical data indicates that this route accounts for the elimination of approximately 60% to 80% of the administered dose of the medicine and its metabolites.


Q: Can Metrocide cause skin reactions or a rash?

A: Skin reactions, including a rash, are documented as possible adverse events associated with the use of Metrocide in official safety information.


Q: How does the body break down Metrocide?

A: The active ingredient in Metrocide is broken down, or metabolized, extensively by the liver. Official clinical pharmacology data indicates that this process primarily involves side-chain oxidation and the formation of glucuronide conjugates.


Q: Is Metrocide considered a 'strong' medicine?

A: The active ingredient, Metronidazole, is officially described in regulatory documents as a potent synthetic antimicrobial agent. This classification reflects its ability to effectively clear severe infections caused by anaerobic bacteria and protozoa.


Q: Does Metrocide interact with common herbal supplements like St. John's Wort?

A: Official labeling includes a general advisory to inform the prescriber about all concomitant medications, including herbal supplements. This precaution is advised because some herbal products are known to influence how the body breaks down and uses prescription medicines.

How should Metrocide be stored and disposed of?

Metrocide (Metronidazole) must be stored and discarded according to specific regulatory requirements defined in the official prescribing information.

Official Storage Requirements

Metrocide is required to be stored at controlled room temperature, typically between 15 C and 25 C (59 F to 77 F). The product must be protected from light and kept away from excess heat and moisture. To maintain stability, the medication must remain in its tightly closed, original container.

For child safety, the medicine must be stored out of the reach and sight of children and pets, as the container may not be child-resistant.

Disposal and Stability Constraints

Official documents indicate that Metrocide oral suspension must be discarded 10 days after opening the container. For disposal of unused or expired product, government guidelines recommend a drug take-back program. Metrocide must not be flushed down a sink or toilet; if a take-back option is unavailable, it should be mixed with an undesirable substance, sealed, and placed in the household trash.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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