Flazole

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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 Flazole

Flazole is identified as a combination medicine administered as a prescription-only product, distinguishing it from single-agent formulations. This product contains two distinct active ingredients: Ofloxacin, an antibacterial from the quinolone class, and Ornidazole, a nitroimidazole derivative. This strategic dual composition is clinically recognized for targeting infections caused by both specific susceptible bacteria and certain parasites, thereby supporting comprehensive treatment for mixed microbial conditions.

Property Description
Active Ingredients Ofloxacin (Quinolone) + Ornidazole (Nitroimidazole Derivative)
Form Tablet (Coated)
Pharmacological Class Broad-Spectrum Antibiotic / Antiprotozoal Combination
General Purpose To eliminate susceptible mixed bacterial and parasitic infection sources
Origin Synthetic Combination

What Type of Antimicrobial is Flazole?

Flazole is categorized as a specialized Systemic antimicrobial agent combining two distinct mechanisms of action to broaden its therapeutic coverage. The presence of the nitroimidazole derivative, Ornidazole, provides established Antiprotozoal action, while Ofloxacin contributes powerful Antibacterial capabilities. This formulation is explicitly positioned to address conditions where the source of infection is suspected to involve multiple pathogen types, such as diarrhea caused by mixed infections.

Understanding the General Purpose of Metronidazole

Although Flazole is a combination product, one of its components, the nitroimidazole derivative, is designed to act as a Pro-drug, meaning it is biologically inactive until it enters the target microbial cell. The general therapeutic purpose of the Flazole combination is the synchronized eradication of infectious microorganisms that are vulnerable to either Ofloxacin or Ornidazole. This dual-action approach is clinically supported for its effectiveness in clearing the infection source quickly and broadly.

Is Flazole a Single Ingredient Medicine?

No, Flazole is specifically a combination product, setting it apart from classic single-agent antibiotics. The inclusion of two distinct active ingredients allows for a synergistic effect that ensures a wide spectrum of microbial disruption and elimination. The typical Dosage form(s) is an oral tablet, designed for oral administration, confirming its identity as a ready-to-use systemic therapy for adults.

What side effects are possible with Flazole?

Possible Side Effects and Safety Information

Flazole's safety profile is defined by the official adverse reactions associated with its two components, Ofloxacin (a fluoroquinolone) and Ornidazole (a nitroimidazole derivative), as classified by regulatory authorities.

Adverse Reaction Scope Official Regulatory Classification
Common Reactions Nausea, vomiting, headache, dizziness, diarrhea, insomnia, and taste disturbances (metallic taste).
System-Organ Classes Effects are officially documented across the Gastrointestinal, Nervous System, Musculoskeletal, Psychiatric, and Skin systems.

Serious Adverse Reactions

Regulatory agencies emphasize the risk of serious, potentially disabling, and permanent reactions associated with the fluoroquinolone component. These serious adverse reactions include tendinitis and tendon rupture (most often the Achilles tendon), peripheral neuropathy (nerve damage in the extremities), seizures, and severe liver problems. The drug may also exacerbate muscle weakness in individuals with Myasthenia Gravis. These serious effects can occur soon after treatment initiation.

Safety Considerations and Limitations

  • Population Risk: Official labeling cites an increased risk of tendon rupture in older adults (over 60 years) and patients concurrently receiving corticosteroids.
  • Exposure Pattern: Tendon rupture may occur during treatment or up to several months after the medicine is discontinued.
  • Restrictions: Caution or restricted use is noted for patients with a history of epilepsy or other central nervous system disorders, as well as those with known QT prolongation (a heart rhythm abnormality).

Overdose and Emergency Response

Overdose and When to Seek Help

The official regulatory documentation for Flazole (Ofloxacin and Ornidazole) overdose focuses on severe, acute manifestations that necessitate immediate medical care.

Documented Overdose Manifestations

Overdose presentations documented in official sources primarily involve the Central Nervous System (CNS), presenting as convulsive seizures, toxic psychoses, confusion, dizziness, and impairment of consciousness. Gastrointestinal symptoms such as nausea, vomiting, and mucosal erosions are also noted. The risk of increased intracranial pressure has been cited in regulatory warnings for one of the components.

Severe Outcomes and Risks

The label documents the potential for life-threatening systemic events, including severe anaphylactic reactions progressing to shock, hepatic necrosis, and the development of potentially irreversible peripheral neuropathy. Musculoskeletal risks such as tendonitis and tendon rupture are also critical concerns noted in the official prescribing information.

Mandated Emergency Action

Regulatory guidance mandates immediate discontinuation of the medicine and consultation with a doctor at the first signs of serious adverse reactions, such as CNS effects, tendon pain, or signs of hepatic failure. Due to the severity of documented outcomes, and the fact that no specific antidote is known, management is strictly limited to symptomatic and supportive treatment. For severe or life-threatening symptoms, immediate consultation with a physician in an emergency department is required.

Population Considerations

Regulatory information highlights that elderly subjects and patients taking corticosteroid drugs have a documented elevated risk of severe musculoskeletal effects following exposure that exceeds the prescribed dose.

Therapeutic Uses of Flazole

Quick Facts

  • Assists in addressing infections caused by susceptible bacteria and parasites.
  • Contributes to the management of certain gastrointestinal and reproductive tract infections.
  • Used in a therapeutic capacity for conditions like bacterial vaginosis, amebiasis, and trichomoniasis.

What Flazole Treats: Main Uses and Benefits

Flazole is a prescription medication utilized in a therapeutic capacity to manage a variety of infections caused by certain susceptible bacteria and parasites. It is appropriate for use in the resolution of infections across several organ systems, when medically determined to be necessary.

Infections of the lower reproductive and urinary tracts, such as trichomoniasis (when confirmed by laboratory testing) and bacterial vaginosis, are among the conditions for which this medication is typically administered. It also serves as a component in the authorized regimen for certain gastrointestinal issues, including amebiasis (amebic dysentery) and giardiasis.

Additionally, Flazole may be used to provide resolution for serious infections caused by specific anaerobic bacteria, such as those affecting the skin, joints, or central nervous system. Its applications also extend to preventing certain post-surgical infections, particularly those related to the gastrointestinal tract, under the direction of a healthcare professional.

Eligibility and Restrictions for Use

The eligibility for Flazole is defined by specific exclusions and restrictions documented in official regulatory labeling. Use is generally restricted to adult patients who do not present with any contraindications.

Contraindicated Populations
Individuals with hypersensitivity to Ofloxacin, Ornidazole, or any member of the quinolone or nitroimidazole antimicrobial classes.
Patients with a past history of tendinitis or tendon rupture linked to fluoroquinolone use.
Patients with a history of epilepsy or an existing Central Nervous System (CNS) disorder with a lowered seizure threshold.
Children and growing adolescents, pregnant women, and breastfeeding women.

Eligibility is conditional for certain pre-existing conditions, requiring caution or dose alteration. Patients with impaired renal function or severe hepatic dysfunction often necessitate adjustment of the dosage regimen. Caution is also required for older adults (over 60), individuals with myasthenia gravis, diabetes (due to dysglycemia risk), or known risk factors for QT interval prolongation.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Official regulatory documentation structures the interaction profile of Flazole (Ofloxacin + Ornidazole) around specific prohibitions, dose adjustments, and timing rules.

Interaction Classifications

Classification Interacting Agents Official Regulatory Constraint
Contraindicated Disulfiram Formal prohibition due to documented risk of psychotic reactions.
Strict Prohibition Alcohol-Containing Preparations Use is strictly prohibited during and for a specified time after therapy due to the risk of a Disulfiram-like reaction.

Pharmacokinetic and Pharmacodynamic Interactions

The Ofloxacin component's absorption is significantly reduced when co-administered with Cation-Containing Oral Products, such as Antacids, Sucralfate, and Iron/Zinc supplements, resulting in lower systemic exposure. Administration of Flazole must be separated by at least two hours before or after these products.

Metabolic interference by the Ornidazole component may increase the effect of oral Coumarin Anticoagulants (e.g., Warfarin), necessitating potential dosage adjustment. Furthermore, co-use with Nonsteroidal Anti-inflammatory Drugs (NSAIDs) may lower the seizure threshold, while combinations with certain products that prolong the QTc interval carry an additive cardiac risk.

Mechanism of Action

Flazole is a nitroimidazole prodrug that targets susceptible anaerobic organisms and certain protozoa. Following passive diffusion across the cell membrane, the drug is activated within the cytoplasm via enzymatic reduction. The intracellular electron transport proteins, such as ferredoxin, transfer an electron to the nitro group of Flazole, generating a highly reactive nitro radical anion. This activation step is thermodynamically favored under the low oxygen tension characteristic of anaerobic environments, limiting the effect on human cells and aerobic organisms. The reduced, activated intermediate is cytotoxic and interacts with intracellular macromolecules. Specifically, the free radicals disrupt the helical structure of the target organism's deoxyribonucleic acid (DNA), leading to strand breakage and inhibition of nucleic acid synthesis. This molecular damage results in the intracellular cascade that ultimately leads to cell non-viability. The maintenance of the concentration gradient promotes continuous drug uptake. At the system level, this pharmacodynamic process modulates the microbial population structure at sites of selective accumulation.

Dosage and Administration Information

How to Use Flazole: Official Administration Guidelines

Flazole, a combination medication containing Ofloxacin and Ornidazole, is a systemic antimicrobial agent administered via the oral route. The official usage patterns are standardized across both the film-coated tablet and the oral suspension for pediatric populations, with instructions explicitly governing dose, frequency, and specific intake conditions.


Administration Protocol

Rule Description
Route of administration: Oral via film-coated tablet or suspension form.
Dosing schedule (Adults): One tablet (200 mg Ofloxacin / 500 mg Ornidazole) per administration.
Frequency: Typically administered twice daily (every 12 hours).
Duration: The total course of treatment commonly ranges from 5 to 10 days.
Tablets: Must be swallowed whole; they are not to be broken, crushed, or chewed.

Contextual Use Requirements

The proper administration of Flazole involves adherence to specific timing and dietary constraints. Milk and dairy products must be avoided during the course of treatment. Additionally, the administration of Flazole must be separated by at least two hours from any products containing polyvalent cations, such as iron, magnesium, aluminum, calcium, or zinc, to prevent interference with the absorption of the Ofloxacin component.

Population-Specific Use

Official labeling mandates that the dose or dosing interval requires adjustment for patients with renal or hepatic impairment. For pediatric patients under eight years of age, the oral suspension formulation is used, with doses ranging from 2.5 mL to 5 mL twice daily. This protocol ensures the systematic application of the medicine over the prescribed period while accounting for varied patient physiological function.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Flazole

The body of research for Flazole, which combines Ofloxacin and Ornidazole, has primarily examined its role against infections where both susceptible bacteria and certain parasites are suspected. This overview summarizes the type of research that has been conducted and what remains uncertain.


Evidence for Use in Mixed Gastrointestinal Infections

Research has explored the Ofloxacin-Ornidazole combination in short-term Randomized Controlled Trials (RCTs) and comparative clinical efficacy studies for conditions involving acute, disruptive episodes of diarrhea. The studies monitored outcomes related to physical discomfort, such as the number and consistency of stools, the change in abdominal pain, and overall clinical status in the observed populations.

Findings describe patterns observed in these studies, where researchers tracked the time over which gastrointestinal symptoms were observed. What remains uncertain is the long-term characterization of outcomes following treatment; follow-up durations were typically limited to the short term. The overall evidence base is limited by smaller study sample sizes and limited availability of comparative evidence.

Evidence for Use in Genitourinary Tract Infections (Bacterial Vaginosis and Trichomoniasis)

Conditions involving the lower reproductive and urinary tracts, such as bacterial vaginosis (BV) and trichomoniasis, were evaluated in Systematic Reviews and Comparative Clinical Trials. For BV, studies explored outcomes related to clinical status, which often involves the measurement of diagnostic criteria and the monitoring of recurrence rates.

Research describes that the evidence frequently focuses on the Ornidazole component as a single agent. Long-term follow-up durations for both conditions were limited, meaning there is insufficient data to characterize the durability of the reported outcomes over extended periods.


Studies in Specific Populations and Research Gaps

Clinical research primarily focuses on short-term changes in the general adult population. Data for certain groups, such as older adults or children, remain insufficient. The research question regarding the specific therapeutic justification of combining Ofloxacin and Ornidazole in a fixed-dose form has been an area of research, which indicates a gap in comparative evidence that fully validates the combination against its single-agent components.

Frequently Asked Questions (FAQ)

Common questions about Flazole (FAQ)


Q: How quickly should someone expect Flazole to start working?

Studies and official information indicate that the active Ofloxacin component often reports an improvement in symptoms, which is generally observed to begin within the first few days of starting treatment.


Q: How long does Flazole typically stay in your system?

Based on pharmacokinetic studies, which examine how a drug moves through the body, the Ornidazole component has an elimination half-life of approximately 12 to 13 hours. This is the time it takes for half of the substance to leave the system.


Q: Can Flazole cause problems with sleep?

Official labeling indicates that insomnia (difficulty in sleeping) is listed as a commonly reported adverse reaction. If difficulty sleeping occurs, it is noted in the drug's safety profile.


Q: Are headaches a common side effect of Flazole?

Regulatory documents describe that headache is listed as one of the commonly reported adverse reactions associated with the use of Flazole.


Q: Are there any common foods that should be avoided while taking Flazole?

Official guidance specifies that milk and dairy products should be avoided during the course of treatment. Additionally, the medicine must be taken at least two hours apart from any products containing polyvalent cations, such as supplements with iron, magnesium, aluminum, calcium, or zinc.


Q: What if I accidentally take two doses of Flazole?

Official documentation describes symptoms that may occur in a situation of overdose, which can include drowsiness, nausea, dizziness, slurred speech, confusion, and facial swelling. Official guidance requires contacting a healthcare professional or emergency services immediately.


Q: What is the difference between Flazole and a generic version of Flazole?

Regulatory standards require that generic versions must contain the identical active ingredients, strength, and dosage form as the branded product. Generics are required to demonstrate bioequivalence, meaning they are expected to work in the body in the same way as the brand name medicine.


Q: Has Flazole been studied in children?

While an oral suspension formulation exists for children under eight years, regulatory documents also state that the clinical research data for this group remains insufficient. Furthermore, growing adolescents are listed among the populations where use is contraindicated.


Q: Is Flazole safe to use if I am elderly?

Official labeling states that caution is recommended for use in older adults (over 60), as there is an increased risk of certain serious adverse reactions, such as tendon rupture.


Q: Why do official documents mention that Flazole is for 'short-term use'?

Official regulatory approval defines the common duration of treatment as short, typically ranging from 5 to 10 days. The body of research primarily focuses on and characterizes short-term outcomes, meaning long-term outcomes are less understood or characterized.


Q: What happens if Flazole is taken for longer than prescribed?

Official guidelines direct that the medicine should be taken only for the prescribed duration. Taking it for longer than prescribed may be associated with an increased risk of certain serious side effects.


Q: Does Flazole have a risk of dependence or withdrawal symptoms?

Official drug safety documentation does not list Flazole as a habit-forming substance. Therefore, it does not typically list the physical dependence or withdrawal symptoms associated with habit-forming medications.


Q: Is Flazole associated with liver problems?

Official labeling indicates that severe liver problems are listed as a serious adverse reaction that may occur with this medicine. Due to this risk, caution and monitoring are often noted as requirements during treatment.


Q: Can Flazole affect blood sugar levels?

Regulatory documentation indicates that the Ofloxacin component can cause changes in blood glucose levels. These changes can include both abnormally low (hypoglycemia) and abnormally high (hyperglycemia) blood sugar.


Q: Are there different forms of Flazole, like tablets, capsules, or liquid?

Flazole is officially supplied as a film-coated tablet and as an oral suspension, which is a liquid form. The oral suspension is primarily used for administration to children and certain other patients.


Q: Can Flazole cause changes in mood or anxiety?

Official documentation reports that adverse reactions can affect the Psychiatric system. These effects may include symptoms such as anxiety, confusion, or changes in mood or behavior.


Q: Is there a warning about Flazole and driving?

Yes. Because the medicine may cause adverse effects like dizziness, visual disturbances, or sleepiness, official information indicates caution regarding driving or operating machinery until an individual is certain how they respond to the drug.


Q: Can Flazole be used by people with kidney disease?

Use in people with renal impairment (kidney disease) requires caution. Official protocols indicate that the dose or dosing interval often needs to be adjusted to account for the patient's reduced kidney function.


Q: What kind of monitoring is needed while taking Flazole?

Due to the potential for effects on the liver and kidneys, monitoring of Liver Function Tests (LFT) and Kidney Function Tests (KFT) may be required. Furthermore, patients with diabetes may require careful monitoring of their blood glucose levels.


Q: How is the effectiveness of Flazole measured in clinical trials?

Studies examined the drug's effectiveness by measuring outcomes such as the change in abdominal pain, the number and consistency of stools, overall clinical status, and recurrence rates of infection in the observed populations.


Q: Is it normal to feel tired after taking Flazole?

Official documents associated with the Ofloxacin component note excessive tiredness as a possible adverse reaction. This effect is sometimes reported, but it is not always classified as a 'common' side effect.


Q: When should a person stop taking Flazole?

Official warnings emphasize that in the event of signs of a serious adverse reaction, such as pain or swelling in a tendon (which can lead to tendon rupture), the treatment should be stopped immediately. A healthcare professional should be contacted immediately after stopping the treatment.


Q: Can Flazole be crushed or split if it's a tablet?

No. The official administration protocol states that Flazole tablets must be swallowed whole. They are not to be broken, crushed, or chewed.


Q: Does Flazole lose effectiveness over time?

The medicine's efficacy (potency) is maintained until the expiry date printed on the packaging, provided it is stored under the specified conditions. Beyond this date, its action may be reduced. Research evidence has not fully characterized the long-term durability of outcomes beyond the short treatment course.


Q: Are there special warnings for people with heart conditions using Flazole?

Caution is required for individuals with heart rhythm abnormalities, specifically QT prolongation. Official guidance also suggests caution for patients with existing heart rhythm issues, heart failure, or a slow heartbeat.


Q: Does Flazole affect the ability to concentrate?

Official safety information reports adverse reactions that affect the Nervous System, including Disturbance in attention. This means that a person's ability to concentrate may be affected.


Q: Can Flazole be used long-term under any circumstances?

Official regulatory approval and prescribing guidelines define Flazole for short-term use only. It is typically prescribed for a limited duration, often ranging from 5 to 10 days, to treat acute infections.


Q: Are there known cases of people having problems stopping Flazole?

Official safety documentation does not list the medicine as having a risk of physical dependence or withdrawal symptoms. However, it is noted that some serious adverse reactions, like nerve damage (peripheral neuropathy), may persist for months after the medicine is discontinued.


Q: Are there any specific lifestyle changes recommended while on Flazole?

Official warnings indicate a need to minimize exposure to sunlight and artificial ultraviolet light, such as sunlamps or tanning beds. This is due to a risk of photosensitivity, which can cause a severe sunburn or rash.

How should Flazole be stored and disposed of?

How to Store and Dispose of Flazole

Flazole (Ofloxacin and Ornidazole tablets) must be stored strictly according to the conditions defined in the official product labeling to maintain stability.

Storage Requirements

Condition Requirement
Temperature Store at a temperature not exceeding 30 C
Protection The medicine must be protected from light and moisture
Container Keep in the container it came in and maintain it tightly closed
Child Safety Keep out of the sight and reach of children

Do not use the tablets after the expiry date printed on the packaging.

Disposal Instructions

Unused or expired Flazole must be handled in accordance with local requirements. Official guidelines advise against disposing of the medicine via wastewater or household waste. The preferred method for disposal is returning the product to an authorized drug take-back location.

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

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