Aciclovir Eye Ointment 3%

How it works

It is phosphorylated by viral thymidine kinase to its active triphosphate, which inhibits viral DNA polymerase and halts herpesvirus DNA replication.

Prescribing in practice

• Confirm the diagnosis of herpes simplex keratitis before treatment, as topical corticosteroids given alone in active dendritic ulceration can cause sight-threatening worsening.
• Apply into the conjunctival sac and continue for a short period after healing to reduce recurrence, as directed by current prescribing references.
• Specialist ophthalmology input is advised, particularly for stromal involvement or treatment failure.

Monitoring

Monitor the corneal lesion with slit-lamp and fluorescein staining to confirm healing and detect resistance or recurrence.

Counselling the patient

• Transient mild stinging or blurred vision after application is common and usually settles.
• Do not wear contact lenses during an active infection or while on treatment.
• Complete the full course and attend follow-up even once symptoms improve.

Evidence & guidelines

Topical aciclovir is an established first-line agent for herpes simplex epithelial keratitis in UK practice and is supported by the Herpetic Eye Disease Study evidence base.