Biaxin pediatric dose calculator
Use this Biaxin pediatric dose calculator to match the prescribed child dose to the exact liquid, tablet, or capsule strength before you give it.
Usual oral clarithromycin dose for children 6 months and older: 15 mg/kg per day, as 7.5 mg/kg every 12 hours (max 500 mg per dose), usually for 10 days. Enter weight for the mL on your bottle; give the dose your child's prescriber ordered.
dose calculator basics
Biaxin pediatric dose calculator details
Use this Biaxin calculator as the fast parent page for weight-based dose checks, mL conversion, common strengths, and the practical safety steps that generic calculator sites often skip.
Formula
mL per dose = (child weight in kg x prescribed mg/kg/day / doses per day) / medication concentration in mg per mL.
Worked example
For a 20 kg child using 15 mg/kg/day divided 2 times daily with 250 mg/5 mL, calculate the daily mg target, divide by the schedule, then convert that mg amount into mL for the selected product.
Safety checks before using the result
- Use the exact product strength in hand before measuring the dose.
- Confirm maximum dose, age limits, and indication-specific cautions when they apply.
- Escalate urgent symptoms or medication reactions instead of repeating doses from calculator output alone.
Practical dosing guide
Before you measure the dose
Use this page to match the prescribed Biaxin plan to the exact product strength and schedule before the first dose. Biaxin is the brand name for clarithromycin.
- Common outpatient uses
- Biaxin, or Clarithromycin, is an antibiotic useful for treating a variety of bacterial infections, including bronchitis and pneumonia.
- Common forms
- Common forms include 125 mg/5 mL oral liquid, 250 mg/5 mL oral liquid, and 250 mg tablet.
- How the schedule is usually written
- Many outpatient plans are given twice daily for 10 days.
Biaxin pediatric medication summary
Biaxin, or Clarithromycin, is an antibiotic useful for treating a variety of bacterial infections, including bronchitis and pneumonia. Especially useful in treating infections in the middle ear, sinus, skin, and throat, its specific dosing options in the calculator make pediatric care streamlined and effective.
Biaxin has a distinct role in pediatric infections involving the respiratory tract, including community-acquired pneumonia, sinusitis, and pharyngitis, especially when *Mycoplasma* or *Legionella* is suspected. It is also used for atypical mycobacterial infections, especially in immunocompromised pediatric patients (like those with HIV). The drug's twice-daily dosing and pleasant taste make it suitable for outpatient use, and its availability in suspension form supports pediatric administration. Compared to erythromycin, clarithromycin causes fewer gastrointestinal side effects and is generally better tolerated. It is metabolized in the liver and has a moderate risk for drug interactions, so it should be used with care in children on multiple medications.
Biaxin indications and common pediatric uses
Biaxin (Clarithromycin) is a trusted antibiotic that helps children fight bacterial infections. Understanding when and how it's used ensures your child receives the right treatment at the right time for their infection.
Community-Acquired Pneumonia (Atypical Pathogens)
Community-Acquired Pneumonia (Atypical Pathogens): Clarithromycin is used to treat pneumonia caused by atypical organisms like *Mycoplasma pneumoniae* and *Chlamydophila pneumoniae*. Often used when beta-lactams are ineffective or atypical pathogens are suspected based on symptoms and age.
Streptococcal Pharyngitis (Strep Throat)
Streptococcal Pharyngitis (Strep Throat): Alternative to penicillin or amoxicillin for children with true IgE-mediated penicillin allergies. Effective against group A Streptococcus when appropriate culture or antigen testing confirms the diagnosis.
Acute Bacterial Sinusitis
Acute Bacterial Sinusitis: Clarithromycin may be used in children with sinus infections who are allergic to first-line beta-lactam antibiotics, particularly when pathogens like *H. influenzae* or *M. catarrhalis* are suspected.
Skin and Soft Tissue Infections
Skin and Soft Tissue Infections: Useful in treating skin infections caused by susceptible organisms such as *Staphylococcus aureus* or *Streptococcus pyogenes*, especially in cases requiring oral outpatient therapy and where beta-lactams are not appropriate.
Disseminated Atypical Mycobacterial Infection (MAC prophylaxis/treatment)
Disseminated Atypical Mycobacterial Infection (MAC prophylaxis/treatment): Clarithromycin is part of standard combination therapy for treating or preventing *Mycobacterium avium complex* (MAC) infections in immunocompromised children, especially those with AIDS.
How to give Biaxin
- Give Biaxin with breakfast and dinner, finish the entire 7-14 day course, and review every new medicine or supplement before continuing clarithromycin so you avoid interactions.
- Shake the suspension 10-15 seconds, measure with the pharmacy syringe, and give every 12 hours—pair with a meal to reduce stomach upset. Cross-check the child’s medicine list before each dose; if a new seizure medicine, heart medication, or grapefruit product was added, pause and call the prescriber before resuming clarithromycin.
- Write the morning/evening dose times on the bottle, set paired alarms, keep flavored chasers ready, and train children old enough to swallow tablets (≈8+ years) so taste battles don’t derail the course.
Biaxin side effects, contraindications, and interactions
Biaxin (clarithromycin) is usually tolerated in children older than 6 months, but side effects still need a clear monitoring plan from day 1. The common problems are stomach upset and metallic taste. The uncommon but higher-risk events are QT-related arrhythmias, clinically significant drug interactions (CYP3A4 inhibition), and liver injury. Most urgent callbacks happen when a new symptom appears after another medication is added, so interaction review should be repeated during treatment.
Common side effects
- Gastrointestinal effects are the most common early complaints (diarrhea, nausea, vomiting, abdominal pain). Most cases improve when doses are given with food and fluids are maintained. Avoid routine anti-diarrheal products in children unless specifically directed. Escalate for bloody stool, fever with abdominal pain, persistent vomiting, or diarrhea that does not improve within 48-72 hours.
- Metallic taste (dysgeusia) is common and can reduce appetite enough to threaten adherence. Families often mistake this for allergy; in most cases it is a known medication effect and reverses after treatment. Practical tactics include cold foods, strong familiar flavors, and rinsing the mouth after each dose. Escalate if oral intake falls, weight drops, or taste changes persist more than 2 weeks after completion.
- QT prolongation and torsade risk are uncommon but serious. Risk rises with congenital long-QT, electrolyte depletion from vomiting/diarrhea, and co-prescribed QT-prolonging agents. High-risk patients should have ECG/electrolyte review before or during therapy. Send for urgent evaluation with syncope, sustained palpitations, chest pain, or unexplained lethargy.
Safety checks
- Immediate hypersensitivity to clarithromycin or other macrolides
- History of macrolide-associated QT prolongation or torsades
- Cholestatic jaundice/hepatic failure linked to prior clarithromycin use
- Concurrent use with cisapride, pimozide, ergot alkaloids, or colchicine
- Congenital long QT syndrome or family history of sudden cardiac death
- Severe hepatic impairment or active hepatitis
Drug interactions
- Review the full medication list with a clinician or pharmacist before combining therapies.
Biaxin mechanism and clinical pearls
Biaxin blocks bacterial protein factories while soaking into the tissues where tough bugs hide. It grabs the 50S ribosome, piles up in lung and ear tissues, and keeps working days after the last dose, so short courses still beat atypicals.
Check CYP3A4 substrates (theophylline, carbamazepine, digoxin, warfarin) before starting Biaxin to prevent toxicity.
Save Biaxin for atypical or beta-lactam–refractory infections so its advantages outweigh its interaction profile.
Move capable kids to tablets after a few suspension doses to eliminate the bitter taste and improve adherence.
Comprehensive medication review prevents life-threatening drug interactions
Intracellular pathogen recognition and action requires different antibiotic approach
Frequently asked questions about Biaxin
Clarithromycin (Biaxin) treats bacterial infections like pneumonia (especially caused by atypical organisms), sinus infections, strep throat (in children allergic to penicillin), and certain skin infections. It is also used for treating or preventing mycobacterial infections in immunocompromised children, and as part of combination therapy for *H. pylori* in gastrointestinal infections. It is not effective for viral illnesses like colds or the flu.
Children typically begin improving within 2 to 3 days of starting clarithromycin. For conditions like strep throat or pneumonia, you may notice a drop in fever and improved energy. However, full symptom resolution may take longer, depending on the infection. If there’s no improvement in 72 hours or if symptoms worsen, follow up with your healthcare provider.
If a dose is missed, give it as soon as remembered unless it’s close to the next dose – in that case, skip the missed one and continue with the regular schedule. Do not double the dose. If your child spits out the medicine right away, and it’s within 15 minutes, you may repeat the dose. If unsure, check with your doctor or pharmacist. Try offering the medicine with food or after something sweet to help with taste issues.
The most common side effects include nausea, mild stomach discomfort, diarrhea, or changes in taste. These are typically mild and improve with food intake or once the course is completed. Rash can occur and should be reported to your doctor, especially if it’s itchy or associated with other symptoms. Serious side effects like yellowing of the eyes or trouble breathing are rare but require immediate medical attention.
Clarithromycin interacts with several medications due to its effect on liver enzymes (CYP3A4 pathway). Always tell your doctor about any medicines your child is taking, including supplements or over-the-counter drugs. In particular, avoid combining clarithromycin with drugs known to prolong the QT interval or those heavily metabolized by CYP3A4 unless under close supervision.
Yes. It’s essential to complete the full prescribed course to fully treat the infection and prevent bacterial resistance. Stopping early may cause the infection to return or allow bacteria to develop resistance. Only stop early if advised by your healthcare provider.
Sources reviewed for Biaxin
FDA Approved Labeling for Biaxin (Clarithromycin)
SourcePediatric Community-Acquired Pneumonia (Atypical Pathogens) Treatment Guidelines
SourcePediatric Streptococcal Pharyngitis (Strep Throat) Treatment Guidelines
SourcePediatric Acute Bacterial Sinusitis Treatment Guidelines
SourcePediatric Skin and Soft Tissue Infections Treatment Guidelines
SourcePediatric Disseminated Atypical Mycobacterial Infection (MAC prophylaxis/treatment) Treatment Guidelines
Source