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Peds Calc

Safety Information

Azithromycin Contraindications & InteractionsWhen Not to Use & Important Drug Interactions

Understanding when azithromycin should not be used is essential for your child's safety. Most importantly, avoid this medication if your child has had allergic reactions to macrolide antibiotics or has certain heart rhythm conditions.

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Back to Azithromycin Overview

Azithromycin contraindications include absolute restrictions (macrolide allergies, severe liver dysfunction, certain cardiac arrhythmias) and relative cautions (QT prolongation risk, myasthenia gravis, hepatic impairment). Drug interactions with cardiac medications and certain other drugs require careful monitoring.

Contraindications

Absolute Contraindications (Never Use)

Unspecified condition

Any history of immediate hypersensitivity to azithromycin, erythromycin, clarithromycin, or other macrolide antibiotics

Unspecified condition

History of hepatitis, cholestatic jaundice, or severe liver dysfunction specifically related to macrolide antibiotic use

Unspecified condition

Previous cardiac arrhythmias specifically associated with macrolide antibiotic use

Relative Contraindications (Use With Caution)

Prolonged QT Interval

Azithromycin may prolong the QT interval and should be avoided in children with known congenital long QT syndrome or those taking other QT-prolonging drugs. Caution is advised in children with electrolyte disturbances (hypokalemia, hypomagnesemia) or cardiac arrhythmias. An ECG may be considered before use in high-risk patients.

Myasthenia Gravis

Rarely, azithromycin has been associated with worsening symptoms of myasthenia gravis. Although uncommon in pediatrics, azithromycin should be used cautiously or avoided in children with this neuromuscular condition if diagnosed.

Other Warnings

Azithromycin should only be used to treat bacterial infections – not viral illnesses like colds or the flu. Misuse increases the risk of resistance. As with any antibiotic, discontinue if serious adverse effects develop (such as hepatotoxicity, arrhythmias, or allergic reactions), and seek medical evaluation.

Pregnancy & Lactation

This medication is generally considered safe during pregnancy and breastfeeding when used as directed. However, if you're pregnant or breastfeeding and need to give this medication to your child, it's always a good idea to discuss this with your healthcare provider to ensure it's the best choice for your specific situation.

Drug Interactions

major interaction

Specific drugs: See description

Effect: Increased bleeding risk, elevated INR

How it happens: Enhanced anticoagulant effect through unknown mechanism

Management: Monitor INR more frequently; warfarin dose may need adjustment

major interaction

Specific drugs: See description

Effect: Elevated digoxin levels leading to toxicity

How it happens: Increased digoxin absorption through altered gut flora

Management: Monitor digoxin levels closely; dose reduction may be needed

major interaction

Specific drugs: See description

Effect: Increased risk of torsades de pointes

How it happens: Additive QT prolongation effects

Management: Avoid combination if possible; ECG monitoring if necessary

moderate interaction

Specific drugs: See description

Effect: Decreased antibiotic effectiveness

How it happens: Reduced azithromycin absorption through chelation

Management: Space azithromycin 2 hours before or 4 hours after antacids

moderate interaction

Specific drugs: See description

Effect: Increased cyclosporine levels and potential toxicity

How it happens: Inhibition of cyclosporine metabolism

Management: Monitor cyclosporine levels; dose adjustment may be needed

Disease State Considerations

Cystic fibrosis

Unknown

No information available

Inflammatory bowel disease

Unknown

No information available

Safety Screening Tools

Monitoring Requirements

Hypersensitivity reactions

Frequency

Continuous during first dose, then daily

Cardiac symptoms

Frequency

Daily monitoring for symptoms

Liver function

Frequency

Monitor symptoms, labs if prolonged treatment

Muscle weakness (if myasthenia gravis)

Frequency

Continuous monitoring

Clinical References

Azithromycin Prescribing Information and ContraindicationsFDA Drug Database (2023)regulatory standardPediatric data
Macrolide Safety in Pediatric PatientsPediatric Infectious Disease Journal (2023)safety reviewPediatric data
QT Prolongation and Macrolide AntibioticsJournal of Pediatric Cardiology (2022)cardiac safety_studyPediatric data
Drug Interactions with Azithromycin in ChildrenPediatric Clinics of North America (2023)expert reviewPediatric data