Azithromycin is a broad-spectrum macrolide antibiotic effective against respiratory, skin, and sexually transmitted infections. Its unique pharmacokinetics allow short treatment courses, typically 3-5 days, with sustained tissue concentrations.
Azithromycin inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit. It demonstrates concentration-dependent bactericidal activity against susceptible organisms including H. influenzae and S. pneumoniae.
This antibiotic comes as tablets (250mg, 500mg), oral suspension, and IV form. The Z-Pak (500mg day 1, then 250mg x4 days) is a common dosing regimen for adults.
Gastrointestinal upset occurs in about 10% of patients. Rare but serious effects include QT prolongation and liver enzyme abnormalities. Allergic reactions are possible.
Increasing resistance in S. pneumoniae and N. gonorrhoeae limits effectiveness in some regions. Culture-guided therapy is recommended when possible.
Tablets require room temperature storage. The suspension remains stable for 10 days after reconstitution when refrigerated. Avoid freezing any formulations.
Compared to erythromycin, azithromycin has better GI tolerance and longer tissue half-life. Clarithromycin has broader coverage but requires twice-daily dosing.
Patients with known macrolide allergy or history of cholestatic jaundice should avoid azithromycin. Caution needed in those with QT prolongation risk.
Pregnancy category B - considered safe when benefits outweigh risks. Excreted in breast milk at low concentrations. Pediatric dosing based on weight.
Increases levels of digoxin, warfarin, and some statins. Antacids reduce absorption if taken within 2 hours. Avoid with pimozide or ergot alkaloids.
May be taken with or without food (though food reduces GI upset). Space other medications appropriately to avoid interactions.
Typical courses range from single-dose (for STIs) to 5 days (respiratory infections). Prolonged use increases resistance risk.
Azithromycin effectively treats community-acquired pneumonia, bronchitis, sinusitis, skin infections, and certain STIs like chlamydia. It's also used for mycobacterial infections in immunocompromised patients.
Its long tissue half-life (68 hours) allows sustained antibiotic activity after stopping medication. This enables shorter treatment courses compared to other antibiotics.
Yes, like all antibiotics it may disrupt normal flora. Women prone to yeast infections may benefit from prophylactic probiotics during treatment.
Yes, the oral suspension is approved for pediatric use from 6 months. Dose is carefully calculated by weight for younger children.
Take it as soon as remembered, then continue normal schedule. Never double doses. For once-daily regimens, take if remembered within 12 hours.
Unlike some antibiotics, dairy doesn't affect absorption. However, high-fat meals may increase GI side effects.
Report any irregular heartbeat or severe diarrhea to your doctor immediately.
Symptom improvement typically occurs within 2-3 days for respiratory infections. Full bacterial eradication continues after completing the course.
Severe dizziness, irregular heartbeat, yellowing skin/eyes, or blistering rash require immediate medical attention.
Moderate alcohol is generally safe but may worsen GI side effects. Heavy drinking should be avoided during treatment.
Azithromycin affects drug metabolism. Antacids require 2-hour spacing, while warfarin and digoxin need closer monitoring.
Add specified water amount to powder, shake well, then refrigerate. Use provided measuring device for accurate dosing.
Not typically first-line for UTIs as most causative organisms are gram-negative. May be used for certain atypical cases.
Complete the full prescribed course unless experiencing severe side effects.