Biclar

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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 Biclar

Quick Facts

Property Description
Active Ingredient Clarithromycin (Prescription-Only)
Form Tablet (Film-coated), Oral Suspension, Injection
Pharmacological Class Macrolide Antibiotic
General Use Treating Bacterial Infections
Origin Semisynthetic

What Type of Antibiotic is Biclar?

Biclar is the trade name for the drug Clarithromycin, which is classified as a semisynthetic macrolide antibiotic used to combat a wide range of bacterial infections. The substance Clarithromycin belongs to the macrolide pharmacological class, a group distinguished by a large molecular ring structure. Clarithromycin is chemically derived from the naturally occurring antibiotic Erythromycin, with a structural modification that enhances its stability and improves absorption when taken orally. This makes it a highly effective systemic anti-infective agent and it is routinely classified as a single-component product.


Composition and Available Forms of Clarithromycin

The active ingredient in Biclar is Clarithromycin, delivered in various forms, primarily for systemic administration. The medicine is commonly available as a film-coated tablet for oral consumption and as granules for oral suspension, which is reconstituted into a liquid, primarily targeting the pediatric patient group or adults who have difficulty swallowing. For acute clinical needs, an intravenous preparation is also available. These different dosage forms ensure Clarithromycin can be reliably administered through the oral route or intravenously, allowing for the delivery of the active substance to the bloodstream.


What is the General Purpose of This Medicine?

The general purpose of Biclar is to assist the body in overcoming bacterial infections by stopping the growth and spread of susceptible microorganisms. Clarithromycin achieves its essential anti-infective function by selectively interfering with the bacteria's ability to create the proteins necessary for their survival and replication. This action effectively reduces the infectious bacterial population, allowing the body's immune defenses to clear the illness and promote recovery from the general symptoms of a bacterial infection, such as those associated with common upper respiratory tract infections.

What side effects are possible with Biclar?

Possible Side Effects and Safety Information

The official safety profile for Biclar (Clarithromycin) organizes adverse reactions by their frequency and the physiological system affected, consistent with regulatory documents like the FDA Prescribing Information and the European Summary of Product Characteristics (SmPC).

Frequency and Organ System Classification

Adverse reactions are classified into categories such as Common, Uncommon, and Not Known (reported post-marketing). The most frequently documented effects are categorized as Common and primarily involve the Gastrointestinal system, presenting as nausea, vomiting, abdominal pain, and diarrhea. Another common reaction affecting the Nervous System is dysgeusia (taste perversion).


Serious Adverse Reactions and Safety Constraints

Regulatory documents highlight the risk of serious adverse reactions, including potentially fatal cardiac arrhythmias. These events involve QT prolongation which can lead to ventricular tachycardia and Torsades de Pointes. The label also documents the potential for hepatotoxicity, ranging from elevated liver enzymes to severe hepatitis and, rarely, fatal hepatic failure. Additionally, the risk of severe hypersensitivity reactions, such as Stevens-Johnson syndrome (SJS), is noted.


Population-Specific Safety Notes

The medicine is officially contraindicated in patients with a history of cardiac arrhythmia, prolonged QT interval, or uncorrected electrolyte imbalances, due to the increased risk of severe cardiac events. A specific safety signal has been documented concerning patients with pre-existing Coronary Heart Disease (CHD), noting a potential increase in long-term mortality risk years after treatment. Furthermore, the drug is restricted in individuals with severe hepatic failure combined with renal impairment, consistent with the officially defined safety limitations.

Overdose and Emergency Response

Overdose Map: Overdose and when to seek help — Official Regulatory Information for Biclar (Clarithromycin)

Overdose Scope

Element Official Regulatory Statement
Documented overdose presentations Primarily presents with symptoms of severe gastrointestinal disturbance, including abdominal pain, vomiting, nausea, and diarrhea.
Physiological systems affected (as stated in label) Gastrointestinal system.
Emergency-response statements (as written in official documents) Treatment for adverse reactions accompanying overdosage should be through supportive measures and the prompt elimination of unabsorbed drug.
When immediate medical help is required (label-derived phrasing only) Seek immediate medical attention for potential overdose, especially if severe symptoms like collapse or seizure occur.

Overdose Classifications (High-Level)

Classification Element Official Regulatory Statement
Overdose-context constraints (as defined in official documents) No specific antidote is known. Clarithromycin serum concentrations are not expected to be appreciably affected by hemodialysis or peritoneal dialysis.

Resulting Overdose Structure

Official overdose statements:

  • Overdose is officially documented to present with signs of severe gastrointestinal disturbance, including symptoms such as abdominal pain, vomiting, nausea, and diarrhea.
  • In the event of overdosage, immediate medical attention is required, and the official procedure includes the prompt elimination of unabsorbed drug and the initiation of supportive measures.
  • Regulatory information states that hemodialysis or peritoneal dialysis procedures are not expected to appreciably affect the drug's serum concentrations.

Connection to the overall overdose profile

Government regulatory documents define the overdose profile primarily by its gastrointestinal manifestations and a mandatory course of action emphasizing supportive treatment and the prompt elimination of unabsorbed drug. Urgent medical help is explicitly required by regulators for severe scenarios, such as collapse, seizure, or trouble breathing. The official profile also includes the critical constraint that no specific antidote is known, and clearance methods like dialysis are documented to be ineffective.

Therapeutic Uses of Biclar

What Biclar Treats: Main Uses and Benefits

Biclar (Clarithromycin) is commonly used to address a range of acute symptomatic conditions driven by susceptible bacterial infections. Its therapeutic benefit focuses on addressing the symptoms related to susceptible bacterial infections to help ease the associated distress and contribute to improved comfort. This macrolide antibiotic is applicable across several key therapeutic domains.

This medication is commonly applied to manage symptoms associated with bacterial infections of the upper and lower respiratory tracts (including pneumonia, bronchitis exacerbations, and sinusitis), otitis media, and uncomplicated skin and soft tissue infections like cellulitis. It is also a core component of regimens used to manage H. pylori manifestations, a condition associated with duodenal ulcers.

In these contexts, the medication helps manage symptom clusters such as fever, localized pain, swelling, and purulent discharge, contributing to a reduction in the overall symptom burden. For patients with a penicillin allergy, it is commonly used as a relevant alternative, providing supportive symptomatic assistance.

Quick Fact: Symptomatic Support
Symptoms to be Managed Fever, localized pain, inflammatory swelling, purulent discharge, abdominal discomfort (H. pylori-related).
Key Clinical Scenarios Acute respiratory episodes, penicillin allergy alternatives, H. pylori management regimens.
Patient Benefit Focus Supports general well-being during symptomatic phases and assists with maintaining functional stability.

Regulatory References

  1. MedlinePlus Drug Information

Eligibility and Restrictions for Use

Eligibility Map: Who can and cannot use Biclar (Clarithromycin)

The official eligibility profile for Biclar is defined by regulatory agencies to ensure safe use, primarily addressing patients with pre-existing conditions and specific life stages.

Category Regulatory Status Affected Population
Populations for whom use is allowed Established use Adults and Adolescents (ge 12 years). Children (ge 6 months), typically via oral suspension.
Populations for whom use is contraindicated Absolute prohibition Patients with known macrolide hypersensitivity or a history of clarithromycin-induced liver dysfunction. Patients with a known history of QT prolongation or ventricular cardiac arrhythmia. Patients with uncorrected hypokalemia or hypomagnesemia. Patients with severe hepatic failure combined with renal impairment.
Populations for whom use is restricted Conditional or Not Recommended Severe renal impairment ( CrCl < 30 mL/min) requires dose adjustment. Infants under 6 months (safety and efficacy not established). Pregnancy (not advised unless no alternative is appropriate).

Connection to the overall eligibility profile

Official regulatory documents categorize who can and cannot use the medicine by establishing clear contraindications for populations at high cardiac risk or with certain liver conditions. For other groups, such as those with severe kidney impairment or those who are pregnant, use is categorized as restricted or not recommended, requiring conditional use as documented in the official labeling.

What should I know about interactions with other medicines?

Interactions with other medicines and products

This section describes documented interaction patterns for Biclar (Clarithromycin) based on official regulatory labeling.

Clarithromycin's primary interaction mechanism is the strong inhibition of Cytochrome P450 3A4 (CYP3A4), which significantly increases the systemic exposure of many co-administered substances. A secondary mechanism is the inhibition of the P-glycoprotein (P-gp) transporter.


Formally Contraindicated Combinations

Co-administration with the following substances is formally prohibited in regulatory documents due to the high risk of serious toxicity or adverse events:

  • Cardiac Agents: Astemizole, Cisapride, Domperidone, Pimozide, and Terfenadine, due to the documented risk of QT prolongation and cardiac arrhythmias.
  • Statins: Lovastatin and Simvastatin, due to the potential for severe increase in exposure, raising the risk of rhabdomyolysis.
  • Other Drugs: Ergot Alkaloids (Ergotamine, Dihydroergotamine), Lurasidone, Lomitapide, and Oral Midazolam.

Pharmacodynamic and Exposure Interactions

Clarithromycin may cause additive pharmacodynamic effects with Quinidine or Disopyramide, increasing the risk of torsades de pointes. Use with Oral Anticoagulants (e.g., Warfarin) requires regulatory monitoring due to the potential for potentiated effects.

Substances that are strong CYP3A inducers, such as Rifampicin or the herbal product St John's Wort, are documented to accelerate Clarithromycin's metabolism, resulting in lower plasma levels.

Administration Constraints

The extended-release formulation of Clarithromycin should be taken with food. A population-specific restriction notes that the co-administration of Colchicine is contraindicated in patients with renal or hepatic impairment.

Mechanism of Action

Clarithromycin functions by targeting the internal machinery of susceptible bacteria, specifically binding to the 23S ribosomal RNA (rRNA) located on the 50S ribosomal subunit. This binding physically obstructs the ribosomal exit tunnel, which immediately halts the process of peptide chain elongation—the creation of new proteins. This targeted interference with the bacterial translation pathway results in essential enzymes and structural components required for cell life and division being insufficiently produced.


The suppression of protein synthesis results in a physiological effect known as bacteriostasis, meaning the drug prevents the bacterial population from multiplying and expanding. By blocking replication, Clarithromycin reduces the overall infectious load, which then allows the host's immune system to engage with a lower concentration of replicating pathogens, contributing to the ultimate clearance of microorganisms. This mechanism is highly selective, as the drug targets only the prokaryotic (bacterial) ribosomal structure, which differs significantly from human cellular machinery.


The drug's mechanism is physiologically limited when bacteria develop specific forms of resistance. The most common constraint involves bacterial enzymes, such as Erm methylase, which modify the ribosomal binding site, thereby preventing the drug from attaching effectively. Additionally, some bacteria can actively pump the drug out of the cell using specialized efflux pumps, which prevents Clarithromycin from reaching the inhibitory concentration required at the 50S subunit target.

Dosage and Administration Information

Biclar is the brand name for the antibiotic clarithromycin, and it must be taken exactly as prescribed by a healthcare professional. Dosing, frequency, and duration of therapy depend on the specific infection being treated, the formulation (immediate-release tablet, extended-release tablet, or oral suspension), and patient-specific factors such as kidney function.

General Administration Guidelines

  • Duration of Treatment: The full course of medication must be completed, even if symptoms improve early. Stopping the antibiotic prematurely can lead to a return of the infection and the development of antibiotic-resistant bacteria.
  • Missed Dose: If a dose is missed, take it as soon as you remember, unless it is almost time for the next scheduled dose. In that case, skip the missed dose and resume the regular schedule. Do not take two doses at the same time to compensate for a missed one.
Formulation Key Administration Instruction
Immediate-Release Tablets Can be taken with or without food. Swallow the tablet whole; do not break, crush, or chew.
Extended-Release Tablets Must be taken with food and swallowed whole. Do not chew or crush, as this alters the slow-release properties of the medicine.
Oral Suspension Shake the liquid well before measuring the dose. Use an oral syringe or medicine spoon provided by your pharmacist to ensure accurate measurement.

If you have moderate or severe kidney impairment, your doctor may need to adjust your dosage schedule.

Recent Clinical Evidence

Research Evidence / Overview of studies for Biclar (Clarithromycin)

This overview describes the types of research and general patterns observed in studies involving Clarithromycin (Biclar), focusing only on the official scientific evidence and what remains uncertain. It does not offer clinical advice or include information on how to use the medication.


Evidence for use in Respiratory Tract and Ear Infections

Research was conducted on Clarithromycin for conditions like pneumonia, sinusitis, and acute bronchitis exacerbations. These studies were mainly short-term Randomized Controlled Trials (RCTs). The research monitored outcomes related to physical discomfort and systemic or functional imbalance, such as how symptoms evolved in the observed populations and rates of measured changes in clinical status.

Findings from these comparative trials described patterns observed in the trials when measured against standard antibiotic regimens. Results regarding its application to target certain, specific types of bacteria have varied across different published studies. Follow-up durations were limited in many of the core trials, meaning the long-term outcomes following treatment are not well characterized.


Evidence for use in H. pylori Management Regimens

Clarithromycin was evaluated in a significant number of RCTs as a core component of multi-drug regimens used to address Helicobacter pylori infection, a condition associated with duodenal ulcer manifestations. These studies focused on the rate of H. pylori eradication, which was monitored typically four to eight weeks after the completion of the short-term drug course.

The data show patterns related to outcomes that may be heavily influenced by the local prevalence of antibiotic resistance. As such, reported eradication success rates were observed in some studies to be lower in geographic regions known to have high levels of resistance to this medicine.


Areas of Research Uncertainty and Study Limitations

The research landscape highlights several areas where evidence remains limited. Across multiple indications, follow-up durations were limited, focusing mainly on the immediate post-treatment period, meaning that the long-term effects are not fully established.

Furthermore, while the evidence contributes to the broader evidence landscape, comparative evidence is lacking for every possible bacterial strain and every comparator drug, and subgroup findings are uncertain for specific complex or vulnerable patient groups.

Frequently Asked Questions (FAQ)

Common questions about Biclar (FAQ)

Q: What types of bacterial infections is Biclar commonly prescribed for?

The official product information indicates that Biclar (clarithromycin) is used to treat mild to moderate bacterial infections. This includes conditions such as pharyngitis, acute sinusitis, certain pneumonias, and uncomplicated infections of the skin. It is also indicated for disseminated mycobacterial infections caused by Mycobacterium avium complex (MAC).


Q: What are the warning signs of a more serious side effect associated with Biclar use?

Official safety information advises being aware of signs of serious liver issues, which can include symptoms like dark urine, jaundice (yellowing of the skin), or tenderness in the abdomen. For severe allergic reactions, signs to watch for are widespread rash, hoarseness, or difficulty breathing. Observing these signs should prompt contact with a healthcare professional.


Q: Is it typical to experience dizziness or confusion while on Biclar treatment?

The official side effect profile lists dizziness as an uncommon adverse reaction associated with clarithromycin. Confusional states (mental changes) have also been reported in post-marketing experience, though their exact frequency is not known. Patients experiencing these effects should report them to their prescriber.


Q: Is it safe to use Biclar while breastfeeding or chestfeeding?

Regulatory documents state that clarithromycin is present in human milk. Official information does not prohibit use, but clarifies that the prescribing physician must weigh the potential benefits to the mother against potential risks to the breastfed infant. Risks reported in exposed infants include diarrhea, rash, and somnolence (drowsiness).


Q: Can people with a known penicillin allergy still use Biclar?

Official prescribing information highlights the need to review a patient's history of hypersensitivity reactions to penicillins or cephalosporins before starting clarithromycin therapy. Biclar belongs to the macrolide class, which is chemically distinct from penicillin.


Q: What does the label say about using Biclar in patients with myasthenia gravis?

Post-marketing reports included in the drug's official label mention the exacerbation of symptoms of myasthenia gravis. This information serves as a safety note for patients with this pre-existing disorder of muscle weakness.


Q: Is Biclar the same type of medicine as Amoxicillin or other common antibiotics?

Biclar (clarithromycin) is classified as a macrolide antibiotic, which is a different pharmacological class than penicillins (like amoxicillin). Official labeling often notes that for certain common infections, penicillin is the drug of choice, positioning clarithromycin as an alternative macrolide.


Q: Why do some people report temporary changes to their hearing when using this medication?

Uncommon adverse reactions reported in official documents include impaired hearing and tinnitus (ringing in the ears). Cases of deafness have also been reported in post-marketing experience. These effects relate to the ear and labyrinth system, and have been observed to be temporary in some cases.


Q: Is there a risk that Biclar could cause a yeast infection?

The official summary of product characteristics lists candidiasis (a type of yeast or fungal infection) and vaginal infection as uncommon adverse reactions. These conditions can occur when antibiotics alter the body's normal balance of microorganisms.


Q: Does Biclar have different approved uses for children compared to adults?

Yes, official prescribing information indicates that Biclar has some different approved uses for children (6 months and older) compared to adults. For example, acute otitis media (middle ear infection) is listed as an indication specifically for pediatric patients, in addition to uses shared with adults.


Q: Why is Biclar sometimes used for an infection called Mycobacterium avium complex (MAC)?

The official labeling indicates that Biclar (clarithromycin) is specifically used for the treatment of disseminated mycobacterial infections caused by the Mycobacterium avium complex (MAC). This reflects its targeted activity against these particular types of bacteria.


Q: What should a patient look out for if they suspect they are having an allergic reaction to Biclar?

Official information advises patients to be aware of signs of a severe acute hypersensitivity reaction. These signs may include a widespread rash, breathing difficulty, or swelling. The labeling advises that the medication should be discontinued immediately if severe allergic signs are observed.


Q: Are there any known effects of Biclar on blood sugar levels (hypoglycemia)?

Official documents indicate that hypoglycemia (low blood sugar) has been reported with the use of clarithromycin. This adverse reaction is considered to be of unknown frequency based on post-marketing data.


Q: Can Biclar cause difficulty falling asleep or staying asleep (insomnia)?

Insomnia (difficulty sleeping) is listed in the official safety profile as a common adverse reaction associated with clarithromycin. This effect relates to the drug's influence on the nervous system.


Q: Are there any restrictions on driving or operating machinery while using Biclar?

Regulatory documents list side effects such as dizziness, confusion, and somnolence (drowsiness). Patients should be aware that if these effects occur, the ability to drive or operate machinery may be affected.


Q: Why is a specific metabolite (14-OH clarithromycin) mentioned in the drug information?

The drug information mentions the 14-OH clarithromycin metabolite because it is microbiologically active. This means that this substance, which the body creates when processing Biclar, still contributes to the overall effectiveness of the drug, particularly against certain bacteria like Haemophilus influenzae.


Q: What are the general effects of a Biclar overdose, according to medical sources?

Reports of overdose symptoms generally include gastrointestinal issues such as abdominal pain, nausea, and vomiting. Official sources have noted that severe overdose may also involve psychological effects, such as temporary confusion or paranoia.


Q: Is there special caution needed when Biclar is used by older adults?

Yes, the official label notes that older adults may need special caution. This is because they are potentially more susceptible to drug-associated effects on the heart’s electrical rhythm, such as the QT interval effect, and are more likely to have pre-existing kidney or heart problems.


Q: Can Biclar cause headaches or changes in vision?

Headache is listed in the official safety profile as a common adverse reaction associated with Biclar. Blurred vision has also been reported in post-marketing data, but its frequency is not known.

How should Biclar be stored and disposed of?

Storage and Disposal Instructions for Biclar (Clarithromycin)

Biclar must be stored under specific conditions to maintain stability and prevent accidental exposure, as mandated by regulatory labeling.


Official Storage Requirements

Requirement Condition
Temperature Store at Controlled Room Temperature (20 C to 25 C) or below 30 C.
Protection Keep in the original container to protect from moisture and light.
Safety Must be kept out of the sight and reach of children.
Handling Do not refrigerate or freeze the tablets.

Disposal Requirements

Unused or expired Biclar should not be disposed of via wastewater or household waste. All waste material must be discarded in accordance with local pharmaceutical waste regulations (e.g., drug take-back programs).

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

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