Bitazol

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Bitazol

Method of action: Antiprotozoal

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

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 Bitazol

Property Description
Active ingredient Ornidazole
Form Film coated tablet, Oral suspension, IV solution
Pharmacological class Antiprotozoal and Antibacterial Agent
General purpose Resolving infections from susceptible protozoa and anaerobes
Origin Synthetic (5-nitroimidazole derivative)

Bitazol: An Identity Defined by Ornidazole and Chemical Class

Bitazol is the trade name for a synthetic, single-ingredient pharmaceutical preparation containing the active substance Ornidazole (INN). Chemically, Ornidazole is classified as a 5-nitroimidazole derivative, a synthetic structure designed for targeted antimicrobial activity. Bitazol functions as a systemic agent, meaning the drug is intended for absorption and distribution throughout the body via the bloodstream to reach the site of infection. This medicine is supplied in multiple forms, including the common film coated tablet, oral suspension, and a solution intended for intravenous infusion.

Pharmacological Type and Dual Action Spectrum

The medicine is broadly classified as an anti-infective agent. Its therapeutic identity is based on a specific dual action spectrum, making it an effective antiprotozoal and antibacterial agent. This dual classification enables it to combat infections caused by susceptible protozoa (single-celled parasites) as well as specific types of anaerobic bacteria. This drug differentiates itself from related nitroimidazoles like metronidazole by its significantly longer half-life in human plasma, a property that is supported by pharmacological studies.

General Purpose as a Targeted Microbial Agent

The core therapeutic purpose of Bitazol is to eliminate these susceptible infections by achieving a definitive protozoacidal and bactericidal effect. The drug works through a precise chemical activation process that occurs only inside the target pathogens, leading to the rapid destruction of the microbe's DNA. This highly focused action is what allows the medicine to resolve the underlying infectious condition. Ornidazole has also been utilized as a preventive measure (prophylaxis) against potential infections during certain surgical procedures.

What side effects are possible with Bitazol?

Possible Side Effects and Safety Information

Official regulatory documents classify the safety profile of Ornidazole, the active ingredient in Bitazol, based on System-Organ Classes and documented frequency bands. Adverse reactions most commonly involve the Gastrointestinal System, where effects such as nausea, vomiting, diarrhoea, dry mouth, and loss of appetite are listed as Uncommon (occurring in 1/1,000 to < 1/100 patients).

The Nervous System is a key focus area in the official safety profile. Neurological effects such as headache, dizziness, somnolence, and tremor are documented, and severe reactions, including seizures, temporary loss of consciousness, and sensory or mixed peripheral neuropathy, are classified as Very Rare [1.3]. Treatment discontinuation is officially specified if neurological symptoms like ataxia, vertigo, or confusion manifest.

Safety Constraints and Considerations

The medicine is subject to several formal safety constraints outlined in regulatory labeling. It is contraindicated in individuals with a known hypersensitivity to Ornidazole or other nitroimidazole derivatives [1.8]. Furthermore, its use is formally restricted in patients with pre-existing conditions, including organic central nervous system diseases, epilepsy, and disseminated sclerosis (multiple sclerosis) [1.8]. The official label advises caution in patients with severe hepatic impairment due to the drug's prolonged elimination, which may require a doubled dosing interval [1.3]. Use is generally restricted during the first trimester of pregnancy and during lactation [1.3].

Overdose and Emergency Response

Overdose and When to Seek Help

Official regulatory documents define a Bitazol (Ornidazole) overdose by the potential for an exaggeration of central nervous system and gastrointestinal symptoms. Documented clinical manifestations may include severe somnolence, headache, nausea, and vomiting.

More severe outcomes requiring attention include convulsions and loss of consciousness. Due to the documented potential for QT interval prolongation, officials mandate specific ECG monitoring in the management of an overdose situation.

Immediate Actions and Required Monitoring

Government guidance requires that immediate medical attention be sought for any suspected overdose. This action must be taken without delay by contacting the National Poisons Information Centre or going to the nearest Accident and Emergency Centre, even if there are no immediate signs of discomfort.

  • Supportive Management: There is no specific antidote known for Ornidazole. Therefore, official management is defined as symptomatic and supportive treatment. The administration of diazepam is explicitly described as the intervention required if cramps occur.
  • Required Evaluation: Hospital evaluation is necessary to assess and manage potential severe effects, including required ECG monitoring for cardiac risk.

Therapeutic Uses of Bitazol

What Bitazol Treats: Main Uses and Benefits

Bitazol is commonly used across domains where additional symptomatic support is needed, specifically targeting certain protozoal and anaerobic infections.

Treating Severe Symptoms of Intestinal Parasitic Infections

This medication is generally applied in conditions characterized by periods of heightened symptoms, such as amoebiasis and giardiasis. It is relevant for managing symptoms that create noticeable functional strain, including severe diarrhea and abdominal cramping associated with these parasites. This use may assist with easing the overall symptom load and helps maintain a sense of stability when symptoms are more noticeable.

“This use can assist with maintaining functional stability during difficult episodes.”

Managing Urogenital, Anaerobic Infections, and Post-Surgical Risk

Bitazol may assist with infections caused by susceptible anaerobic bacteria, often used in cases of deep-seated purulent processes or urogenital conditions like trichomoniasis. It is applied in clinical settings that involve acute or unstable symptom patterns, where symptoms may include fever or localized discomfort. The medicine is commonly used to help with supporting patients during difficult episodes by easing distress and contributing to improved comfort. Its use is relevant in clinical contexts that involve acute or disruptive symptom patterns, including amoebiasis, giardiasis, trichomoniasis, and preoperative prophylaxis in specific surgical contexts.

Quick Fact: Support for Symptoms that Create Noticeable Functional Strain

This medicine is commonly used to help with symptoms related to systemic imbalance and irritative states arising from susceptible infections.

Regulatory References

  1. New Zealand Medsafe Datasheet

Eligibility and Restrictions for Use

Official Eligibility for Bitazol

The eligibility to use Bitazol (Ornidazole) is strictly defined by regulatory documents, distinguishing between absolute prohibitions and conditional use.

Absolute Contraindications

  • Hypersensitivity: Individuals with known allergy to Ornidazole or any other nitroimidazole derivative must not use this medicine.
  • Pregnancy: Use is contraindicated during the First Trimester of Pregnancy.

Restricted and Conditional Use

Eligibility may be conditional based on certain medical states:

  • Severe Hepatic Impairment: The drug’s clearance is affected; eligibility is conditional on a mandated doubling of the dosing interval.
  • CNS Disorders: Caution is required in patients with pre-existing diseases of the Central Nervous System (CNS), such as epilepsy or multiple sclerosis.
  • Blood Disorders: Use requires monitoring, specifically pre- and post-therapy leukocyte counts, for patients with a history of blood dyscrasias.
  • Reproductive Status: Use is not recommended in pregnant women beyond the first trimester or while breastfeeding, unless the clinical need is determined to be absolute.
  • Age Groups: The drug is established for adults. While permitted for children, the tablet strength may be unsuitable for the smallest paediatric doses.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Official Interaction Profile

The interaction profile for Bitazol (Ornidazole) is officially defined by an absolute substance prohibition and several pharmacokinetic interactions that alter plasma drug concentrations.

Category Official Regulatory Information for Bitazol
Medicinal product categories with documented interactions Coumarin anticoagulants, Barbiturates, Histamine H2 antagonists, Lithium salts.
Specific interacting medicines (if explicitly listed) Warfarin, Phenobarbital, Cimetidine, Lithium.
Mechanistic basis of interactions (only if stated in label) Inhibition of hepatic metabolism; Altered drug clearance.
Interaction-related restrictions Contraindicated co-administration with alcohol (ethanol).
Population-specific interaction notes Hepatic impairment may heighten the severity of interactions due to reduced drug clearance.

Regulatory-Documented Interaction Patterns

The official regulatory documents establish that co-administration with alcohol (ethanol) is a contraindicated combination due to the potential for a documented disulfiram-like pharmacodynamic reaction. Separately, Bitazol is officially documented to inhibit the hepatic metabolism of certain co-administered drugs, such as coumarin anticoagulants like Warfarin. This inhibition results in an official increase in the anticoagulant’s plasma concentration and effect.

Furthermore, drugs like Cimetidine are noted to cause an increase in Bitazol's own concentration by officially reducing its clearance, while Phenobarbital is documented to reduce Bitazol's concentration by increasing its clearance. Co-administration with Lithium is also documented to increase Lithium plasma concentrations. Regulatory caution notes that in patients with hepatic impairment, this reduced drug clearance can officially amplify the severity of these established drug interactions.

Mechanism of Action

The pharmacological action of Bitazol (Ornidazole) is initiated by a unique two-step selective mechanism that targets the fundamental biochemistry of susceptible pathogens. ### Selective Bioactivation and Microbial TargetingThe drug is a prodrug that only becomes active inside susceptible anaerobic bacteria and protozoa. These organisms contain low-redox potential enzymes (like ferredoxin) that reduce the drug's NO2 group, transforming it into highly reactive and toxic nitro-radical intermediates. The selective enzymatic reduction confines the activation process to the target microbes, as host cells lack these specific activating enzymes.### Radical-Mediated DNA Disruption and Pathogen EliminationThe primary physiological consequence stems from the radical's interaction with the pathogen's genetic material. The cytotoxic intermediates rapidly attack the Microbial DNA, causing strand breaks and compromising the integrity of the genome. This damage immediately prevents the pathogen from conducting vital functions, such as DNA replication and transcription, which are essential for cellular viability and replication. This mechanism results in the cessation of function, producing a bactericidal and protozoacidal effect.### Functional Constraint in Anaerobic EnvironmentsThe entire mechanism is functionally constrained by oxygen tension. The presence of oxygen competes with the reductive process and can re-oxidize the active radical intermediate back to the inactive parent drug (futile cycling). This condition limits the drug's maximum efficacy to low-oxygen environments, confining the maximal activity to anaerobic or microaerophilic environments.

Dosage and Administration Information

How to Use Bitazol

Bitazol (Ornidazole) administration follows established protocols, emphasizing appropriate route selection, precise dosing schedules, and population-specific modifications. The medicine is available for systemic use via oral forms, such as the 500 mg film-coated tablet, or as a solution for intravenous (IV) infusion used for severe systemic or acute infections. The choice of administration route often dictates the setting of use, with IV forms typically transitioning to oral forms as clinical status allows.

Oral administration involves taking the medicine after meals to aid proper use. Dosing frequency and duration vary significantly by indication; some conditions, like giardiasis, may utilize a single 1 g or 1.5 g dose, while others, such as intestinal amoebiasis, require a 5 to 10 day course of 500 mg twice daily. When used for surgical prophylaxis, a specific schedule is followed, beginning with an IV dose administered 30 minutes prior to the procedure, followed by post-operative dosing for 3 to 5 days. IV solutions must be diluted to a concentration of 5 mg/mL or less and infused slowly over 15 to 30 minutes.

Specific administration logic applies to certain patient groups. For pediatric use, dosing is determined by body weight (25 mg/kg to 40 mg/kg), and in cases of severe hepatic impairment, the clinical protocol involves the dosing interval being doubled. No dose adjustment is necessary for renal impairment. A key procedural requirement for treating trichomoniasis is the concomitant treatment of the sexual partner with the same oral regimen.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Bitazol

Evidence for Use in Amoebiasis

Research examining Bitazol for amoebiasis—a condition characterized by conditions involving periods of heightened symptoms such as severe diarrhea and abdominal discomfort—has primarily involved Randomized Controlled Trials (RCTs) and comparative studies. These studies were conducted to explore how symptoms change over time and included both adults and children diagnosed with the infection. Researchers monitored two main outcomes: the parasitological clearance rate (whether the E. histolytica parasite was cleared from stool) and clinical clearance (the measured evolution of outcomes related to physical discomfort).

Studies reported specific measurements of parasitological clearance observed at the conclusion of treatment and during follow-up. Research exploring the timeframe for the measured evolution of acute outcomes related to physical discomfort was conducted. Some comparative reports documented patterns observed in relation to other established treatments in the same drug class.

However, certainty remains low in some areas. Long-term outcomes are not fully established, meaning there is limited information for how patients fared months or years after treatment, especially regarding the recurrence of the parasite. Additionally, evidence quality varies across studies due to differences in how the infection was diagnosed and how the trials were designed internationally.

Evidence for Use in Giardiasis

The evidence base for Bitazol in treating giardiasis is derived from numerous Randomized Controlled Trials (RCTs), often summarized in systematic reviews and meta-analyses. Research explored different treatment approaches, including single-dose versus multi-day regimens. These studies were relevant in trials assessing short-term or episodic symptom patterns and included both children and adults with the infection. The main outcomes studied were the parasitological cure (absence of the G. lamblia parasite) and clinical cure (research explored the timeframe for the measured evolution of acute symptoms).

Studies reported measured parasite clearance rates in acute cases. Findings describe patterns observed in the studies related to the measured evolution of outcomes linked to inflammatory or irritative states in the gut. The research provides context on how this medicine was evaluated in settings involving short-term symptom changes, often comparing it directly to other anti-protozoal agents.

Despite the volume of research, heterogeneity (variability in study design) is noted across some comparative trials, particularly regarding dosing schedules. Follow-up durations were limited in many studies. Therefore, long-term effects are not fully established regarding the sustained absence of the parasite and the rate of late reappearance. Data for certain groups remain insufficient regarding the optimal use in individuals who have recurrent or hard-to-clear infections.

Evidence for Use in Trichomoniasis

For trichomoniasis, the evidence was studied for primarily through Randomized Controlled Trials (RCTs), many of which focused on the comparative evaluation of single-dose schedules. These studies examined populations of women and men presenting with the infection. The researchers monitored two main outcomes: the microbiological cure (confirmed absence of the T. vaginalis organism) and the clinical cure (resolution of urogenital symptoms).

Research describes the measured rates of microbiological clearance across the various regimens evaluated. Studies report how symptoms evolved in the observed populations, and findings indicate that the medicine was observed in settings where symptoms became more noticeable. The data also documented the patterns observed when using single-dose treatment options for this condition.

Research is ongoing to fully understand potential resistance patterns over time. Subgroup findings are uncertain for specific populations, such as those who are immunocompromised. The results apply only to the populations studied, meaning findings may not fully generalize to all individuals with the infection.

Evidence for Use in Anaerobic Infections and Surgical Prophylaxis

Research has examined Bitazol in the context of various anaerobic bacterial infections and its use in reducing infection risk during specific surgeries. This evidence includes Randomized Controlled Trials (RCTs) and comparative studies that included surgical patients and those with deep-seated infections. The studies monitored endpoints related to the resolution of identified infections and the reduction of post-surgical infection rates.

Studies report how symptoms evolved in the observed populations of patients with existing anaerobic infections. Prophylaxis research highlighted patterns observed related to the frequency of infections after surgery. Because of the wide variety of infections studied, the data show patterns related to different outcomes depending on the anatomical site involved.

Evidence quality varies across studies because research often compares Bitazol to other active anti-anaerobic medicines rather than a non-active control, limiting direct insight into absolute effects. Comparative evidence is lacking for some head-to-head trials against certain other antimicrobials. The follow-up durations were limited in many of the treatment studies, and the optimal duration for use in surgical prophylaxis is still being explored across different procedures.

Long-Term Studies and Follow-up

The majority of key clinical trials for Bitazol explored short-term symptom changes, meaning they focused on outcomes measured immediately after or within a few weeks of treatment completion. Therefore, the follow-up durations were limited for most indications.

There is limited information for long-term outcomes regarding the sustained absence of protozoal parasites or the durability of the reported clearance rates over many months or years. Studies monitored outcomes over defined time intervals, but research specifically focusing on the long-term impact on outcomes reflecting daily functioning or activity level beyond the acute phase remains insufficient. Therefore, long-term effects are not fully established.

Evidence in Special Populations

Research has explored Bitazol in certain special populations, particularly children with protozoal infections like giardiasis and amoebiasis. Studies observed patient responses in these younger populations, often examining various dosing schedules tailored for their use.

Limited information is available concerning the use of Bitazol in patients with certain comorbidities (other existing health issues) or specific populations defined by disease severity strata. Subgroup findings are uncertain or limited for groups such as older adults who may have multiple concurrent health conditions. The results apply only to the populations studied and do not provide comprehensive findings for every patient group.

What is Still Uncertain About Bitazol Research

While research contributes to the broader evidence landscape, there are several areas where certainty remains low or where further studies would be beneficial. The main evidence gaps include a lack of consistent, long-term follow-up data across all indications to fully characterize sustained clearance and low relapse rates over time.

Furthermore, comparative evidence is lacking for some head-to-head trials against newer or alternative anti-infective agents. The evidence quality varies across studies due to methodological differences (such as small sample sizes or limited blinding) in older international trials. Ultimately, research provides context but not individual predictions. Evidence highlights what is known — and what is still uncertain regarding the long-term outcomes in diverse patient groups.

Key Studies & References

  1. Efficacy of 5-Nitroimidazoles for the Treatment of Giardiasis: A Systematic Review of Randomized Controlled Trials
  2. Ornidazole Tablets 500 mg - SUMMARY OF PRODUCT CHARACTERISTICS (Regulatory Dossier/Monograph)

Frequently Asked Questions (FAQ)

Common questions about Bitazol (FAQ)


Q: What are the most commonly reported side effects of Bitazol?

A: Official regulatory documents list several common side effects, primarily affecting the gastrointestinal system and nervous system. These include symptoms such as headache, nausea, vomiting, dizziness, and loss of appetite. These effects are generally categorized as uncommon, meaning they affect less than 1 in 100 patients.


Q: Does Bitazol affect my liver function?

A: Official information indicates that caution is necessary if a patient has severe hepatic impairment (serious liver issues) because the drug’s processing and clearance can be slowed down. Some official reports have also noted uncommon side effects such as temporary increases in liver enzyme values and jaundice. Concerns about liver health are best addressed by consulting a healthcare professional.


Q: What does current medical research say about the long-term safety of Bitazol?

A: The official documentation for Bitazol is primarily based on short-term clinical trials that were required for the drug’s approval. Because of this focus, safety data and outcomes that extend many months or years beyond the standard course of treatment are not fully established or detailed in regulatory files.


Q: Is it safe to take Bitazol if I have a history of stomach issues?

A: Regulatory information lists common gastrointestinal side effects such as nausea, vomiting, and diarrhea that can occur while taking Bitazol. If a patient has a pre-existing condition like inflammatory bowel disease (IBD) or ulcers, specific advice on the risk and management of these side effects is a topic that can be discussed with their prescribing clinician.


Q: Is it normal to have a mild headache when starting Bitazol?

A: Headache is a documented side effect of Bitazol, though it is usually classified in the uncommon frequency band. Experiencing this at the start of therapy is possible. If a headache is severe or persistent, guidance can be sought from a healthcare provider.


Q: Can Bitazol cause fatigue or drowsiness?

A: Official safety profiles indicate that Bitazol can cause somnolence, which means drowsiness, as well as dizziness. The term 'fatigue' (extreme tiredness) is not consistently listed across all official safety profiles, but if drowsiness is experienced, it can affect daily activities.


Q: How common is it to experience dizziness with Bitazol?

A: Dizziness is a documented adverse reaction to Bitazol. According to regulatory documents, it is typically categorized as uncommon, meaning it occurs in less than 1 in 100 people who take the medicine.


Q: Can Bitazol cause an allergic reaction?

A: Yes, Bitazol is contraindicated (should not be used) if there is a known allergy to the active ingredient, Ornidazole, or any other drug in the nitroimidazole class. Like all medicines, there is a risk of severe allergic reactions, and severe allergic reactions require immediate medical attention.


Q: Can I take Bitazol if I'm already taking a supplement like magnesium or vitamin D?

A: The official regulatory documents list specific drug and alcohol interactions but do not typically provide information on non-regulated dietary supplements like magnesium or vitamin D. All supplements and vitamins are best discussed with a healthcare professional.


Q: Can Bitazol interfere with the effectiveness of birth control pills?

A: Official documents do not explicitly list hormonal contraceptives (birth control pills) among the confirmed drug interactions. However, caution is noted regarding the drug’s use in women of childbearing potential, and it is important to confirm all medication use with a doctor or pharmacist.


Q: Are there any known interactions between Bitazol and common cold medications?

A: Regulatory documents list specific drug categories and prescription medicines that interact with Bitazol, but they do not list general over-the-counter cold and flu remedies. Checking the active ingredients of cold medicine for potential interactions and consulting a pharmacist is important.


Q: Can Bitazol affect my mood or cause anxiety?

A: Official safety information focuses on nervous system effects like confusion and somnolence (drowsiness). While mood changes or anxiety are not explicitly listed in all official side effect profiles, any new or concerning mental or emotional changes can be reported to a healthcare provider.


Q: Does Bitazol have a risk of dependence?

A: Bitazol is classified as an antimicrobial agent used to treat specific infections. Regulatory documents and official product information do not mention or suggest a risk of dependence or addiction associated with the use of this medication.


Q: What happens if I take too much Bitazol accidentally?

A: In the event of an overdose, regulatory documents state that the symptoms experienced are generally the same as the listed side effects, but they would be more severe. If an overdose is suspected, contacting emergency medical services or a poison control center immediately is the recommended action.


Q: Can I drink coffee while I'm on Bitazol?

A: The official product information does not list an interaction between Bitazol and caffeine or coffee. The only beverage explicitly contraindicated (must be avoided) is alcohol (ethanol), due to a specific interaction risk.


Q: Is it okay to drive or operate machinery while taking Bitazol?

A: Official documents advise caution. Since Bitazol can cause central nervous system effects such as dizziness, somnolence (drowsiness), or confusion, the ability to perform tasks that require alertness, like driving or operating machinery, may be impaired. These activities are best avoided if symptoms of impairment occur.


Q: Does Bitazol affect fertility?

A: Studies conducted in male rats showed that high doses of ornidazole may cause infertility by affecting sperm. Regulatory documents state there is currently no specific reproductive or fertility data available from studies conducted in humans.


Q: Are there any known long-term complications associated with Bitazol use?

A: The official documentation focuses on short-term safety, and long-term outcomes are not fully established for all uses. However, specific rare and severe complications, such as peripheral neuropathy (nerve damage), are noted in the safety profile as a key area for monitoring if treatment is prolonged.


Q: Is Bitazol recommended for post-operative recovery?

A: Regulatory documents approve Bitazol for the prophylaxis (prevention) of certain infections that can occur during surgical procedures. It is not approved or recommended as a general treatment for pain or other aspects of recovery management after surgery.


Q: How does Bitazol affect the body's natural processes?

A: Bitazol is designed as a highly targeted antimicrobial agent. Its mechanism of action focuses on susceptible anaerobic microbes and protozoa, where it chemically damages their DNA. The drug is not intended to alter the body's healthy cellular or physiological functions.


Q: What are the side effects that require immediate medical attention when taking Bitazol?

A: Official warnings emphasize that severe neurological symptoms should be reported immediately. These include symptoms like seizures, temporary loss of consciousness, vertigo, confusion, or the onset of new peripheral neuropathy (tingling/numbness). These symptoms are noted as reasons to seek medical guidance regarding treatment continuation.


Q: Can I take Bitazol with multivitamins?

A: The official documents list specific drug interactions but do not generally mention multivitamins. As a precaution, it is advisable to consult a healthcare professional regarding any combination of prescribed medicines and over-the-counter supplements.

How should Bitazol be stored and disposed of?

Official Storage Conditions

Bitazol (Ornidazole) must be stored at a temperature not exceeding 30°C and kept in a cool dry place. The medicine requires protection from excess moisture and heat; therefore, storage in high-humidity areas, such as a bathroom or near a sink, is prohibited. The tablets must remain in their original blister pack until the time of use, and the medicine must not be taken after the labeled expiry date.

Child Safety and Disposal

The product must be KEPT OUT OF REACH OF CHILDREN. Regulatory guidance suggests storing the medicine in a secure, locked cupboard above a specified height. For disposal, any unused or expired Bitazol must be discarded in accordance with local requirements. Patients should consult their pharmacist for specific instructions on the safe disposal of leftover tablets.

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

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