Medicines for Herpes simplex eye infections

What it is

A herpes simplex eye infection is an infection of the eye caused by the herpes simplex virus — the same virus that causes cold sores. The virus can affect the eye, most importantly the cornea (the clear window at the front of the eye), causing an infection called herpes simplex keratitis, and can also affect the surface of the eye and eyelids. It usually affects one eye. Because the herpes simplex virus stays in the body after a first infection, herpes simplex eye infections can recur. The symptoms of a herpes simplex eye infection can include: a red, painful eye; watering; sensitivity to light (photophobia); a feeling of something in the eye or discomfort; blurred vision; and, sometimes, blisters or a rash on the eyelid or around the eye. It is important because, although it can be mild, an infection affecting the cornea can, if not treated appropriately, damage the cornea and threaten vision — repeated or severe infections can cause corneal scarring and affect sight. Two very important points make prompt, correct treatment essential. First, a herpes simplex eye infection needs to be diagnosed and treated appropriately, usually with specific antiviral treatment, and prompt treatment helps protect the eye and vision. Second — and crucially — steroid eye drops (which are sometimes used for other causes of a red or inflamed eye) can make a herpes simplex eye infection much worse and cause serious harm to the eye if used without appropriate antiviral treatment and specialist guidance, so they must not be used for a red eye unless prescribed for the specific situation by an eye specialist. This is one reason a red, painful eye — particularly with sensitivity to light or reduced vision, or a known history of eye herpes — should be assessed rather than self-treated. Herpes simplex eye infections are managed by prompt assessment and antiviral treatment, usually with the involvement of eye care services (an optician can direct, and an eye specialist/ophthalmologist often manages the infection), and, for recurrent infections, sometimes preventive treatment. The key messages are that herpes simplex eye infections are caused by the cold sore virus and can affect the cornea and threaten sight if untreated, that prompt assessment and antiviral treatment matter, and that steroid eye drops must be avoided unless prescribed by a specialist.

How it is treated

Herpes simplex eye infections are managed by prompt assessment and antiviral treatment, usually with eye care services, and — importantly — avoiding steroid eye drops unless prescribed by a specialist; prompt, correct treatment protects the eye and vision. Because a herpes simplex eye infection can affect the cornea and threaten sight, and because a red, painful eye can have various causes (some needing different treatment), it is important that a red, painful eye — particularly with sensitivity to light, reduced or blurred vision, or a known history of eye herpes — is assessed promptly rather than self-treated. Assessment is usually by eye care services: an optician (optometrist) can assess and direct care, and a herpes simplex eye infection affecting the cornea is often assessed and managed by an eye specialist (ophthalmologist), who can examine the eye in detail (for example with special dye and a slit lamp, which can show the characteristic pattern of a corneal herpes infection). Treatment is usually with specific antiviral treatment — for example antiviral eye ointment or drops, and/or antiviral tablets, depending on the situation — to treat the infection and help it heal, guided by the assessment; prompt treatment helps protect the cornea and vision. A crucial point in management is that steroid eye drops must not be used for a herpes simplex eye infection unless specifically prescribed and monitored by an eye specialist as part of appropriate treatment — because steroids can make the viral infection much worse and cause serious harm to the eye if used inappropriately; this is why a red eye should not be treated with leftover or over-the-counter steroid drops, and why correct diagnosis matters. Follow-up with the eye specialist ensures the infection is healing and monitors for any complications or recurrence. Because herpes simplex eye infections can recur (as the virus stays in the body), some people who have recurrent infections may be given preventive (suppressive) antiviral treatment to reduce recurrences and protect the eye, guided by the specialist, and are advised to seek prompt assessment if symptoms recur. It is important to seek prompt attention for a red, painful eye, especially with reduced vision, sensitivity to light, or a history of eye herpes, and urgently if vision is affected, as protecting the eye and sight depends on prompt, correct treatment. The reassuring messages are that herpes simplex eye infections, although they can threaten sight if untreated, are usually treatable with prompt antiviral treatment and eye specialist care, that avoiding steroid eye drops (unless prescribed by a specialist) is essential to prevent harm, and that recurrent infections can be managed and, where needed, prevented; so prompt assessment of a red, painful eye (particularly with a history of eye herpes or reduced vision), correct antiviral treatment, and avoiding inappropriate steroid drops are the keys to managing it.