Chloramphenicol Eye Drops

• Bacterial conjunctivitis — the main use
• Bacterial blepharitis, sometimes, as ointment
• Minor corneal abrasions, to prevent infection while healing
• Before and after certain eye procedures

It does nothing for viral or allergic conjunctivitis, which together account for most red, sticky eyes.

Drops

• One drop every two hours for the first 48 hours, then four times daily
• Continue for 48 hours after the eye looks normal — usually about five days in total

Ointment

Applied at night, or three to four times daily if used alone. It blurs vision for a few minutes, which is why it suits bedtime.

Technique

1. Wash your hands
2. Pull the lower lid down to make a pocket and drop into that, not onto the eyeball itself
3. Do not let the nozzle touch your eye, lashes or fingers — that contaminates the bottle
4. Close the eye and press gently on the inner corner for a minute, which keeps the drop on the eye rather than draining down the tear duct
5. Wait five minutes between different drops

Storage

Drops are usually kept in the fridge; discard the bottle 28 days after opening, whatever is left in it.

No significant systemic drug interactions at the doses absorbed from eye drops.

No monitoring is required for a standard short course.

What matters is duration. Courses run about five days and should not be extended repeatedly — partly because prolonged use encourages resistance, and partly because an eye still red after a week is an eye that needs a different diagnosis rather than a longer course.

Avoid using with other eye preparations without spacing them by five minutes.

Chloramphenicol eye drops are sold over the counter at any pharmacy for a few pounds, without a prescription, for adults and children over two. Own-brand versions cost less than the branded ones for exactly the same drug.

There is no financial reason to obtain this on a private prescription, and we would not encourage it.

What costs nothing and often works

Bathing the eye with cooled boiled water and clean cotton wool, and a cold compress. For viral conjunctivitis this is the treatment, and for mild bacterial conjunctivitis it is frequently enough while it settles on its own.

Where money is worth spending

On being assessed, if the eye is painful, the vision has changed, or you wear contact lenses. Those are the situations where the diagnosis matters far more than the drop does.

Finish about five days — 48 hours beyond the eye looking normal — and then stop. Discard the bottle 28 days after opening regardless.

If it has not worked

An eye that is no better after five to seven days needs reassessing rather than a second course. The usual explanations:

• It was viral all along — which is the commonest answer by a distance, and viral conjunctivitis can take two to three weeks
• It is allergic — itch is the giveaway, and it needs an antihistamine drop
• Allergy to the drops themselves — the eye and lids got worse on treatment
• Blepharitis — a chronic lid margin problem needing lid hygiene rather than antibiotics
• Something that was never conjunctivitis — which is why pain and visual change change the plan

Alternatives

• Fusidic acid eye drops — twice daily, sometimes preferred in pregnancy
• Antihistamine or mast-cell-stabiliser drops — for allergic conjunctivitis
• Lubricating drops and lid hygiene — for blepharitis and dry eye
• Nothing at all — a legitimate and frequently correct choice for mild conjunctivitis

Do I actually need antibiotic drops for a red eye?

Usually not. Most conjunctivitis is viral, and most bacterial conjunctivitis clears by itself within one to two weeks. Antibiotic drops shorten bacterial cases modestly — they are a convenience more than a necessity for most adults.

How do I tell viral from bacterial?

Bacterial tends to be stickier — thick yellow-green discharge, lids gummed together in the morning. Viral tends to be waterier, often follows a cold, and typically starts in one eye then moves to the other.

Itching as the main symptom points to allergy rather than either.

Do I need to stay off work or school?

Conjunctivitis is contagious, but exclusion is not usually required in the UK. Wash your hands frequently, do not share towels or pillowcases, and do not rub your eyes.

Can I wear my contact lenses?

No — stop until 24 hours after treatment finishes and the eye is normal. A red eye in a contact lens wearer also deserves a lower threshold for being seen, because a corneal ulcer is a genuine risk and it threatens sight.

Can I use them in pregnancy?

Usually avoided unless clearly necessary, and fusidic acid drops are often preferred. Ask before using them.

Why must I throw the bottle away after 28 days?

Because the preservative stops being reliable and the bottle becomes a route for infection back into the eye. Keeping a half-used bottle for next time is a genuinely bad idea with eye drops.

My eye hurts rather than feels gritty. Does that matter?

Yes, considerably. Conjunctivitis is gritty and irritable rather than painful. True pain, light sensitivity, or any change in vision means the eye needs looking at today, not treating with drops.