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Macrolide Antibiotic — Bacterial Conjunctivitis / Trachoma / Blepharitis Pregnancy: 'No effect on pregnancy is anticipated, since systemic exposure to azithromycin is negligible. AZYTER can be used during pregnancy.' Breastfeeding: 'Limited data indicate that azithromycin is excreted in breast milk, but, considering the low dose and the low systemic availability, the doses taken by the new-born are negligible. Consequently, breast feeding is possible during the treatment.' Fertility: 'Animal data do not suggest an effect of the treatment of azithromycin on male and female fertility. Human data are lacking. However, no effect on fertility is anticipated, since systemic exposure to azithromycin is negligible.' (SPC section 4.6)

Azithromycin 1.5% Eye Drops

Brand names: AzaSite, Azithrocin Eye

Azithromycin eye drops are a topical macrolide antibiotic used for bacterial conjunctivitis and for trachomatous (Chlamydia trachomatis) conjunctivitis.

Adult dose

Dose: Local antibacterial treatment of purulent bacterial conjunctivitis, and of trachomatous conjunctivitis caused by Chlamydia trachomatis, due to susceptible strains (azithromycin 15 mg/g eye drops, solution in single-dose container): instil one drop in the conjunctival fornix
Route: Ocular - instilled into the conjunctival fornix (eye drops, single-dose container)
Frequency: Twice a day, morning and evening, for three days
UK SPC section 4.2, Adult population: 'Instil one drop in the conjunctival fornix twice a day, morning and evening, during three days. It is unnecessary to prolong treatment beyond three days. Adherence to the dosing regimen is important for the success of treatment.' Elderly: no dose adjustment is necessary. Strength (section 2): each gram of solution contains 15 mg of azithromycin dihydrate (equivalent to 14.3 mg azithromycin); one 250 mg single-dose container contains 3.75 milligrams of azithromycin dihydrate. The SPC prints no maximum dose. Method (section 4.2): wash hands before and after instillation; avoid touching the eye or eyelids with the dropper tip; discard the single-dose container after use and do not keep it for subsequent use. Section 4.4: it is not necessary to continue instilling after the end of treatment on the third day, even if residual signs remain; symptomatic relief generally occurs within 3 days and if there is no improvement after 3 days the diagnosis should be reconsidered; contact lenses should not be worn by patients with bacterial conjunctivitis; the solution must not be injected, swallowed or used for peri- or intra-ocular injection. Scope: this card covers only the licensed ocular indications of the pinned product (Azyter 15 mg/g). Blepharitis, named in this page's category, is not a licensed indication in this SPC and no blepharitis dose is given. Oral (systemic) azithromycin regimens, including for trachoma, are not covered by this SPC. Children: the licence includes children from birth to 17 years and section 4.2 states 'No dose adjustment is necessary' in the paediatric population; no separate paediatric regimen is transcribed here. Neonates (section 4.4): non-trachomatous conjunctivitis caused by Chlamydia trachomatis and conjunctivitis caused by Neisseria gonorrhoeae require systemic treatment, systemic Chlamydia infection (e.g. pneumonia, bacteraemia) may accompany conjunctivitis in neonates and infants below 3 months, and the product is not intended as prophylactic treatment of bacterial conjunctivitis in newborn infants. Use a children's formulary for any under-18 dosing.

Dose adjustments

Renal

Not addressed in the SPC; systemic exposure to azithromycin after ocular instillation is negligible (sections 4.4 and 4.6).

Hepatic

No dose adjustment is stated in the SPC. Section 4.4: fulminant hepatitis potentially leading to life-threatening liver failure has been reported with systemic azithromycin; 'In ophthalmic use, this risk is not relevant since systemic exposure to the active ingredient is negligible'.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via MHRA Products — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

  • Hypersensitivity to azithromycin, to any other macrolide or to the excipient listed in section 6.1 (section 4.3)

Side effects

  • Very common (1/10 or more): ocular discomfort (pruritus, burning, stinging) upon instillation (section 4.8)
  • Common (1/100 to under 1/10): blurred vision, sticky eye sensation, foreign body sensation upon instillation (section 4.8)
  • Uncommon (1/1,000 to under 1/100): angioedema, hypersensitivity; conjunctivitis, allergic conjunctivitis, keratitis, eczema of the eyelids, eyelid oedema, eye allergy, conjunctival hyperaemia, increased lacrimation upon instillation, erythema of the eyelid (section 4.8)
  • Not known: toxic epidermal necrolysis, drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome, exfoliative dermatitis, acute generalised exanthematous pustulosis (by extrapolation of systemic exposure) (section 4.8)
  • Rare serious allergic reactions have been reported with macrolides including azithromycin: angioneurotic oedema, anaphylaxis (rarely fatal), AGEP, SJS, TEN (rarely fatal) and DRESS; if an allergic reaction occurs, discontinue and institute appropriate therapy (section 4.4)
  • In paediatric clinical trials the safety profile was similar to that in adults (section 4.8)

Interactions

  • No specific interaction study has been performed; none of the interactions described for orally administered azithromycin is expected because no azithromycin is detectable in plasma after ocular instillation (section 4.5)
  • Concomitant treatment with another eye drops solution: leave an interval of 15 minutes between the two instillations, and instil this product last (section 4.5)

Monitoring

  • Reconsider the diagnosis if there are no signs of improvement after 3 days (section 4.4)
  • Discontinue treatment in the event of an allergic reaction; the possibility of reappearing allergic symptoms when symptomatic therapy is discontinued should be borne in mind (section 4.4)
  • Contact lenses should not be worn by patients with bacterial conjunctivitis (section 4.4)
  • Neonates: non-trachomatous chlamydial conjunctivitis and gonococcal conjunctivitis require systemic treatment, and systemic infection should be suspected in neonates and infants below 3 months (section 4.4)

Clinical monograph

How it works

It binds the bacterial 50S ribosomal subunit and inhibits protein synthesis, giving a bacteriostatic effect against susceptible organisms.

Prescribing in practice

  • It is not indicated for the deeper structures of the eye and should not be used to treat keratitis or intraocular infection.
  • Discontinue and reassess if hypersensitivity or worsening occurs, and reconsider the diagnosis if there is no improvement.
  • Avoid contact lens wear during active infection and treatment.

Monitoring

Monitor clinically for resolution of conjunctival signs and for any local hypersensitivity reaction.

Counselling the patient

  • Transient stinging, blurred vision or eye discomfort after instillation is common.
  • Do not wear contact lenses until the infection has cleared.
  • Complete the prescribed course even if the eye improves quickly.

Evidence & guidelines

Topical azithromycin is an established treatment for bacterial and trachomatous conjunctivitis as reflected in current prescribing references.

Reference: MHRA Drug Safety Update 2013 (Azithromycin QTc); WHO SAFE Strategy for Trachoma; SPC AzaSite; RCOphth Bacterial Conjunctivitis Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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