First-lineZithromax
Azithromycin
Macrolide
Single-dose cure for chlamydia in pregnancy; PPROM latency arm of ORACLE.
OralIV
First-line for
- Chlamydia in pregnancy (1 g PO single dose)
- Adjunct in PID
- Pertussis
Mechanism
Binds 50S ribosomal subunit — bacteriostatic, long tissue half-life.
“Chlamydia in pregnancy = 1 g once”
- Test of cure at 3–4 weeks (NAAT)
- Treat partners
Dosing
- Chlamydia
- 1 g PO once
- Pertussis
- 500 mg day 1, 250 mg days 2–5
Contraindications
- AbsoluteMacrolide hypersensitivity
- CautionLong QT, severe hepatic impairment
Side effects
- GI upset
- QT prolongation
- Hepatitis (rare)
Fetal & maternal notes
- • First-line for chlamydia in pregnancy
- • Compatible with lactation
Key interactions
Statins
Caution↑ myopathy risk
Warfarin
Caution↑ INR
QT-prolonging drugs
AvoidTorsades
Clinical pearls
- 💡 Replaces doxycycline (teratogenic — teeth/bone) and erythromycin (GI intolerance)
Content last reviewed: REPLACE_ME (e.g. 2026-07)
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