Conjunctivitis - Antibiotic Prescribing

Comments from Expert Advisory Group

  • Viral conjunctivitis accounts for the majority of conjunctivitis cases and usually presents in patients over 5 years old, in the summer months, with watery discharge, no glued eye in the morning and photophobia.
  • Most acute bacterial conjunctivitis infections are self-limiting and do not require topical antibiotics. They are usually unilateral with yellow-white mucopurulent discharge. Symptoms usually resolve within 5-7 days without treatment.
  • Self-care advice for the patient presenting with sticky eye/conjunctivitis.
  • Public Health advice states that children with conjunctivitis do not need to stay out of school/ childcare if child is well but school/ childcare provider should be informed.

If topical antibiotic considered necessary:

  • Consider a delayed prescription for 3 days to see if symptoms resolve with self-care and without antibiotic eye drops.
  • Prolonged or recurrent use of any topical antimicrobial agent should be avoided where possible as it leads to the emergence of antimicrobial resistance.
  • Fusidic acid has minimal Gram-negative activity. Note that in contact lens wearers, infection may be Gram-negative.
  • Chloramphenicol is not recommended in pregnancy or breastfeeding.
  • Patient should be informed to seek medical advice if no improvement after 2 days of treatment.
  • Note: In April 2021, the manufacturer’s product license for Chloromycetin®  0.5% Redidrops  restricted their use in children under 2 years due to risk of toxicity from an excipient boron. In August 2022, having considered the EMA guideline on excipients and other information such as the small conjunctival sac in children under 2 years, the HPRA has concluded that the benefits outweigh the potential risks for children (including those under 2 years), for Chloromycetin® 0.5% Redidrops, when topical antibiotic treatment is considered necessary.

When to swab, refer or seek specialist input:

  • Consider swabbing if chronic infection, recurrent infection or no improvement with treatment choice. Note: Adenovirus conjunctivitis can last for 2-3 weeks.
  • Refer patients with severe pain, suspected corneal infection, suspected gonorrhoea/ Chlamydia infection, or chronic infection of >1 month. Have a low threshold of referral for contact lens wearers.
  • Seek specialist advice for severe cases as systemic treatment may be required such as:
    • Risk of keratitis e.g. infiltrate over cornea, moderate to severe pain, decreased vision. This is especially common in contact lens wearers
    • If hyperacute conjunctivitis (rapid onset within 12-24 hours, severe purulent discharge). In such cases be aware of the risk of Neisseria gonorrhoeae; if suspected, refer for diagnosis and systemic treatment. Newborn infants in the first week or life, as well as teenagers and adults are at risk of Neisseria gonorrhoeae eye infection. Neisseria gonorrhoeae eye infections present a high risk of complications including uveitis, severe keratitis and corneal perforation.
    • If haemorrhagic conjunctivitis in the first month of life, this may be Chlamydia trachomatis. If suspected, refer for diagnosis and systemic treatment.
    • Teenagers and adults are also at risk of Chlamydia trachomatis conjunctivitis, especially if there is no response to standard topical therapy. Such cases often present with a chronic (longer than 2 weeks) low-grade irritation and mucous discharge in a sexually active person. Pre-auricular lymphadenopathy may be present.
    • Suspected Herpes simplex or zoster infection


If topical antibiotic is required:

  • Consider referral to ophthalmology if symptoms persist for more than 7 to 10 days.
Drug Dose Duration +/- Notes
1st choice options

Chloramphenicol 0.5% drops



Adults and Children
Apply two drops to the infected eye(s) every 3 hours during waking hours or more frequently if required. 

Treatment should be continued for 48 hours after resolution of symptoms, in general for a maximum of one week

  • Drops can be used in conjunction with the ointment (apply at night) if desired as the ointment at night allows prolonged contact time.
  • Presence of ointment on the eye may blur the vision with use during the day.
  • Chloramphenicol eye drops should be used with caution in children <2 years.
  • Chloramphenicol is not recommended in pregnancy or breastfeeding.




Chloramphenicol 1% Ointment

(Unlicensed medication)



Adults and Children:
Apply to the infected eye(s) every 6 hours

(or apply at night only if used in conjunction with chloramphenicol drops)

Treatment should be continued for 48 hours after resolution of symptoms, in general for a maximum of one week



2nd choice options

Fusidic Acid 1 % Viscous Eye Drops Suspension


Adults and Children:
Apply one drop to infected eye(s) every 12 hours


Treatment should be continued for 48 hours after resolution of symptoms, in general for a maximum of one week


Patient Information

  • HSE A-Z Conjunctivitis webpage
  • Care should be taken with application of eye drops not to touch the dropper off the eye to reduce risk of spreading/ prolonging infection.
  • Wash hands after application with liquid soap and water or decontaminate with alcohol rub.

Safe Prescribing (visit the safe prescribing page)

Reviewed October 2022

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