Indications: Treatment of acute otitis media due to H. influenzae, M. catarrhalis, or S. pneumoniae; pharyngitis/tonsillitis due to \ S. pyogenes, community- acquired pneumonia due to Chlamydia pneumonia, H. influenzae, M. pneumoniae, or S. pneumoniae; pelvic inflammatory disease (PID) due to C. trachomatis, N. gonorrhoeae, or M. hominis; genital ulcer disease (in men) due to H. ducreyi (chancroid); acute bacterial exacerbations of chronic obstructive pulmonary disease (COPD) due to H. influenzae, M. catarrhalis, or S. pneumoniae; acute bacterial sinusitis due to H. influenzae, M. catarrhalis, or S. pneumoniae; prevention of Mycobacterium avium complex (MAC) (alone or in combination with rifabutin) in patients with advanced HIV infection; treatment of disseminated MAC (in combination with ethambutol) in patients with advanced HIV infection; skin and skin structure infections (uncomplicated) due to S. aureus, S. pyogenes, or S. agalactiae; urethritis and cervicitis due to C. trachomatis or N. gonorrhoeae

Cautions: in patients with a predisposition to QT interval prolongation (including electrolyte disturbances and concomitant use of drugs that prolong the QT interval).

Macrolides may aggravate myasthenia gravis.

Pregnancy: manufacturers advise use only if adequate alternatives not available.

Breast-feeding: present in milk (use only if no suitable alternatives).

Hepatic impairment: use with caution in severe liver disease (may cause hepatotoxicity).

Renal impairment: use with caution if eGFR less than 10 ml/minute/1.73 m2

Contra-indications: Hypersensitivity to azithromycin, other macrolide antibiotics, or any component of the formulation; history of cholestatic jaundice/hepatic dysfunction associated with prior azithromycin use.

Side Effects: Gastrointestinal: Diarrhea, nausea, pruritus, skin rash Gastrointestinal: Abdominal pain, anorexia, stomach cramps, vomiting. Genitourinary: Vaginitis. Acute renal failure, ageusia. Aggressive behavior, anaphylaxis, anemia, angioedema, anosmia, auditory disturbance, candidiasis, cardiac arrhythmia (including ventricular tachycardia), chest pain, cholestaticjaundice, conjunctivitis (pediatric patients), deafness, DRESS syndrome, eczema, edema, enteritis, erythema multiforme (rare), fungal dermatitis, fungal infection, gastritis, hearing loss, hepatic failure, hepatic necrosis, hepatitis, hyperactivity, hyperkinesia, hypotension, increased liver enzymes, insomnia, interstitial nephritis, jaundice, leukopenia, melena, mucositis, nephritis, neutropenia (mild), oral candidiasis, pancreatitis, pharyngitis, pleural effusion, prolonged Q-T interval on ECG (rare), pseudomembranous colitis, pyloric stenosis, seizure, skin photosensitivity, Stevens-Johnson syndrome (rare), syncope, taste perversion, thrombocytopenia, tongue discoloration (rare), torsades de pointes (rare), toxic epidermal necrolysis (rare), vesiculobullous rash.

Dose: Respiratory-tract infections (except community acquired pneumonia) otitis media, skin and soft-tissue infections, adult : oral capsule 500 mg once daily for 3 days or 500 mg on first day then 250 mg once daily for 4 days.

CHILD: over 6 months 10 mg/kg once daily (max. 500 mg once daily) for 3 days; or based on body-weight (15–25 kg) 200 mg once daily for 3 days (26–35 kg) 300 mg once daily for 3 days (36–45 kg) 400 mg once daily for 3 days Community-acquired pneumonia low to moderate severity.

ADULT over 18 years 500 mg once daily for 3 days or 500 mg on first day then 250 mg once daily for 4 days high severity

ADULT over 18 years by intravenous infusion, 500 mg once daily for at least 2 days, then by mouth, 500 mg once daily; total duration 7–10 days (unlicensed when used by mouth for over 3 days) Uncomplicated gonorrhoea, Uncomplicated genital chlamydial infections and non-gonococcal urethritis

ADULT over 18 years, 1 g as a single dose Lyme disease mild to moderate typhoid due to multiple-antibacterial- resistant organisms [unlicensed indications],

ADULT over 18 years 500 mg once daily for 7–10 days (7 days in typhoid).