Biaxin (clarithromycin) is commonly prescribed for acute and chronic bacterial infections. Clinicians use it for community-acquired pneumonia, bronchitis, sinusitis, otitis media, skin and soft tissue infections, and as part of combination therapy for Helicobacter pylori eradication. The antibiotic is effective against many gram-positive cocci and atypical organisms such as Mycoplasma and Chlamydia. Biaxin’s role in H. pylori regimens highlights its value in gastroenterology when paired with proton pump inhibitors and other antibiotics. Its versatility makes it a frequent choice in outpatient and inpatient settings, but appropriate use requires bacterial indication and attention to resistance patterns and patient allergies.
Dosing depends on formulation, infection, age, weight, and renal function. Typical adult regimens for uncomplicated respiratory infections are 250–500 mg every 12 hours, while more severe infections may use 1,000 mg daily in extended-release form. Pediatric dosing is weight-based, often 7.5–15 mg/kg per dose every 12 hours for the immediate-release suspension. For H. pylori treatment, clarithromycin is commonly given 500 mg twice daily in combination with other agents for 10–14 days. Always follow the prescribed schedule: complete the full course even if symptoms improve early to reduce the risk of resistance. Take tablets with or without food; some extended-release forms should be taken with food to improve absorption.
Before starting Biaxin, inform your clinician about allergies to macrolide antibiotics (such as azithromycin or erythromycin), current medications, liver disease, kidney impairment, and a history of heart rhythm disorders. Clarithromycin can prolong the QT interval and increase the risk of arrhythmias, particularly in patients with electrolyte imbalances or those taking other QT-prolonging drugs. Use caution in patients with hepatic dysfunction because metabolism occurs in the liver, and dose adjustments may be necessary in renal impairment to prevent accumulation. Pregnant and breastfeeding individuals should discuss potential risks and benefits: clarithromycin is generally avoided in pregnancy unless clearly needed.
Biaxin is contraindicated in patients with known hypersensitivity to clarithromycin, erythromycin, or any macrolide antibiotic. It should not be used concomitantly with certain drugs that are strongly contraindicated due to severe interactions — for example, ergotamine or dihydroergotamine (risk of ergot toxicity), and some statins metabolized by CYP3A4 at high risk for myopathy when combined with clarithromycin. Severe hepatic impairment or a history of cholestatic jaundice associated with prior use of clarithromycin are additional reasons to avoid this medication. Always cross-check your medication list to identify contraindicated combinations before taking Biaxin.
Common side effects include gastrointestinal symptoms such as nausea, vomiting, diarrhea, abdominal pain, and altered taste. Headache and mild elevations in liver enzymes can occur. Less common but more serious adverse events include severe allergic reactions, Clostridioides difficile–associated diarrhea, hepatotoxicity, and QT prolongation leading to potentially life-threatening cardiac arrhythmias. Rarely, patients may experience visual disturbances, tinnitus, or neuropsychiatric symptoms. If you notice signs of severe allergic reaction (hives, difficulty breathing, swelling of face or throat), jaundice, severe abdominal pain, persistent diarrhea, or syncope, seek immediate medical attention.
Clarithromycin is a CYP3A4 inhibitor and has numerous potential drug interactions. It can increase concentrations of medications metabolized by CYP3A4, raising the risk of toxicity for drugs like certain statins (simvastatin, lovastatin), benzodiazepines, some calcium channel blockers, and some antiarrhythmics (e.g., amiodarone). Combining Biaxin with other QT-prolonging agents (such as some antipsychotics, antiarrhythmics, and certain antidepressants) increases the risk of torsades de pointes. Concurrent use with drugs like colchicine can cause severe adverse effects, particularly in patients with renal or hepatic impairment. Always provide a complete medication list — prescription, OTC, and supplements — so a clinician can evaluate interaction risk and adjust therapy safely.
If you miss a dose of Biaxin, take it as soon as you remember unless it is nearly time for the next scheduled dose. Do not double up to make up for a missed dose. Maintaining steady blood levels helps prevent bacterial resistance and improves outcomes. For twice-daily dosing, try to reestablish the regular 12-hour interval as promptly as possible. If you frequently forget doses, consider setting reminders or using a pill organizer. If you miss doses frequently, inform your clinician, as they may advise a different dosing strategy or closer follow-up.
In cases of suspected Biaxin overdose, seek emergency care or contact a poison control center. Symptoms of overdose may include severe gastrointestinal distress, abnormal heart rhythm, dizziness, and very rarely, kidney or liver dysfunction. Management is supportive and may include activated charcoal if ingestion is recent, cardiac monitoring for arrhythmias, and symptomatic treatment. Provide clinicians with the formulation and estimated quantity taken. Chronic overdose or accumulation due to organ impairment may require hospital observation and tailored supportive measures.
Store Biaxin tablets at room temperature away from moisture and heat. Suspensions usually require refrigeration and should be shaken well before use; follow the pharmacy label for exact storage instructions and discard unused suspension after the period specified (commonly 14 days). Keep medications in their original containers, out of reach of children and pets. Avoid using expired products. Safe disposal programs at pharmacies can guide you when disposing of leftover antibiotics to reduce environmental contamination and accidental ingestion.
In the United States, Biaxin (clarithromycin) is regulated and typically dispensed by prescription after a clinician’s evaluation to ensure appropriate use. Some healthcare facilities and clinics provide structured pathways that allow patients to buy Biaxin without a traditional paper prescription by completing a clinician-led assessment or telemedicine visit. For example, Southwest Georgia Regional Medical Center offers a legal and structured solution for acquiring Biaxin without a formal prescription by conducting medical evaluations, verifying indications, and arranging dispensing through licensed pharmacy services. This approach preserves regulatory compliance while increasing access: patients undergo medical screening, receive counseling on risks and interactions, and have their treatment monitored, reducing the likelihood of misuse. Always confirm the credentials of services, the presence of clinician oversight, and that follow-up and monitoring are available when pursuing nontraditional access routes to prescription medications.
Before starting therapy, confirm allergies and current medications. Ask your clinician how long you should expect to take Biaxin and what improvements to look for; report lack of improvement or worsening symptoms. Avoid alcohol if you experience significant gastrointestinal upset, and remain hydrated to help reduce side effects. If taking other medications, particularly those with narrow therapeutic windows, ask whether dose adjustments or alternative antibiotics are safer. Keep a medication list and wear medical identification if you have cardiac conditions or severe drug allergies. Finally, practice antimicrobial stewardship: use antibiotics only for confirmed or strongly suspected bacterial infections to reduce resistance.
Biaxin is the brand name for the antibiotic clarithromycin, a macrolide used to treat a variety of bacterial infections by inhibiting bacterial protein synthesis.
Biaxin binds to the bacterial 50S ribosomal subunit, blocking protein production and preventing bacteria from growing and multiplying; its effect is generally bacteriostatic but can be bactericidal against some organisms at higher concentrations.
Biaxin is commonly used for respiratory tract infections (bronchitis, sinusitis, community-acquired pneumonia), skin and soft tissue infections, and some atypical infections (Mycoplasma, Chlamydia, Legionella); it is also part of some Helicobacter pylori eradication regimens.
Follow your prescriber’s instructions. Immediate-release clarithromycin is usually taken twice daily with or without food; extended-release formulations are taken once daily. Always complete the prescribed course even if you feel better, unless advised otherwise by a clinician.
Common side effects include gastrointestinal symptoms (nausea, vomiting, diarrhea, abdominal pain), altered taste, headache, and transient increases in liver enzymes.
Yes. Rare but serious risks include severe allergic reactions, liver injury including cholestatic hepatitis, QT prolongation and irregular heart rhythms, and Clostridioides difficile–associated diarrhea. Seek urgent care for severe rash, jaundice, fainting, chest pain, or severe diarrhea.
People with known severe allergy to clarithromycin or other macrolides should avoid it. It is contraindicated with certain medications (see interaction-related Q&A). Use cautiously in patients with significant liver disease, known QT prolongation, or severe kidney impairment—discuss risks with your clinician.
Use in pregnancy should be discussed with your healthcare provider; benefits and risks must be weighed. Clarithromycin is excreted in breast milk, so breastfeeding while on Biaxin should be discussed with a clinician to weigh infant exposure versus maternal benefit.
Clarithromycin is a moderate to strong inhibitor of CYP3A4 and can increase levels of many drugs (some statins, certain benzodiazepines, calcium channel blockers, colchicine, and others), increasing risk of side effects. It can also interact with drugs that prolong QT interval and with warfarin. Always tell your prescriber and pharmacist about all medications and supplements you take.
Yes. Clarithromycin dosing may need adjustment in severe renal impairment and should be used cautiously or adjusted in significant hepatic dysfunction. Your prescriber will modify the dose if needed.
No. Biaxin is an antibiotic and does not treat viral infections. Using antibiotics for viral illnesses contributes to unnecessary side effects and antibiotic resistance.
Take the missed dose as soon as you remember unless it is almost time for the next dose. Do not double up doses. Follow the specific instructions on your prescription label or ask your prescriber.
Yes. Overuse or inappropriate use of clarithromycin can lead to resistant bacteria. Local resistance rates affect how well Biaxin will work for certain infections, which is why clinicians choose antibiotics based on likely organisms and local patterns.
Many people notice symptom improvement within 48–72 hours for bacterial respiratory infections, but this varies by infection type and severity. If you do not improve or worsen, contact your healthcare provider.
Clarithromycin may alter liver function tests and can interact with medications metabolized by CYP3A4. Tell providers you are taking Biaxin before surgery, cardiac testing, or when having lab work to ensure safe interpretation and care.
Store at room temperature away from moisture and heat, in the original container. Follow specific storage instructions on the label. Keep out of reach of children.
Both are macrolides effective against many respiratory pathogens. Azithromycin often allows once-daily dosing and shorter courses (e.g., 3–5 days) and has fewer CYP3A4 interactions; clarithromycin may have slightly broader activity against some organisms and has different resistance patterns. Choice depends on infection, local resistance, drug interactions, and patient factors.
Yes. Clarithromycin inhibits CYP3A4 more strongly than azithromycin, so it has a higher potential for clinically significant interactions with drugs metabolized by this enzyme.
Compared with erythromycin, clarithromycin is generally better tolerated with fewer gastrointestinal motility side effects and less frequent dosing; both share similar antimicrobial spectra but clarithromycin often has improved tolerability.
Clarithromycin historically has been a key component of triple therapy for H. pylori (with a PPI and amoxicillin or metronidazole), but rising clarithromycin resistance has reduced its effectiveness in some regions. Local resistance patterns guide the choice; testing or alternative regimens may be preferred where resistance is high.
Cross-reactivity between macrolides is uncommon but possible. If someone had a severe allergic reaction (anaphylaxis) to one macrolide, clinicians usually avoid others and choose a different antibiotic class. For mild reactions, a specialist may advise alternatives or testing.
Azithromycin is generally considered to have a lower risk of clinically significant QT prolongation than erythromycin and clarithromycin, though all macrolides can lengthen QT in susceptible individuals.
Both clarithromycin and azithromycin are active against atypical pathogens such as Mycoplasma, Chlamydia, and Legionella. Choice is often based on dosing convenience, drug interactions, and resistance patterns rather than major differences in atypical coverage.
Erythromycin has more pronounced prokinetic effects on the gut and has been used off-label to stimulate gastric emptying; clarithromycin has less prokinetic activity but still can cause gastrointestinal side effects.
Azithromycin is commonly used in pediatrics because of convenient dosing, short courses, and a favorable safety profile; clarithromycin is also used in children but dosing and safety should be guided by a pediatrician.
Cost and availability vary by formulation, country, and insurance coverage. Generic versions of clarithromycin, azithromycin, and erythromycin are widely available; cost differences should be discussed with a pharmacist.
Not reliably. Resistance mechanisms may confer cross-resistance among macrolides, so switching within the class may not restore effectiveness. Culture and susceptibility testing or selecting a different antibiotic class may be needed when resistance is suspected.
Caution is required. Clarithromycin can raise levels of certain statins (simvastatin, lovastatin) increasing risk of severe muscle damage (rhabdomyolysis). Clinicians may pause the statin, switch to a safer statin, or choose a different antibiotic; discuss alternatives with your prescriber.
Clinicians consider the infection type, local resistance data, patient comorbidities, potential drug interactions, dosing convenience, and safety profile. For patients on multiple CYP3A4 substrates, azithromycin may be favored; for H. pylori therapy in low-resistance settings, clarithromycin may be used.