Antibiotic eye drops and ointment
Chloramphenicol
A broad antibiotic used mainly as eye drops or ointment for bacterial conjunctivitis.
What is Chloramphenicol?
Chloramphenicol is a broad antibiotic, but in the UK it is used most often as eye drops or eye ointment to treat bacterial conjunctivitis (an infected, red, sticky eye). You can buy it from a pharmacy for this purpose without a prescription, and it usually clears the infection within a few days. The drops are placed in the eye several times a day and the ointment is often used at night, which is why the two are sometimes combined. The much rarer but serious blood disorder linked to chloramphenicol is associated with the oral and injected forms used for severe infections, not with normal eye-drop use.
Education and reference only. This is a plain-language guide to Chloramphenicol — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Chloramphenicol is an antibiotic that stops bacteria from multiplying. In the UK its everyday role is in the eye: chloramphenicol eye drops and eye ointment are a standard treatment for bacterial conjunctivitis, the kind of eye infection that makes the eye red, gritty and sticky with discharge. Many products can be bought directly from a pharmacy for adults and children over a certain age. The same antibiotic also exists as tablets, capsules and injections for a small number of serious infections, but these systemic forms are reserved for hospital or specialist use because of a rare but serious effect on the bone marrow.
How it works
Chloramphenicol works by getting inside bacteria and blocking the machinery they use to build proteins, which they need in order to grow and divide. With this machinery jammed, the bacteria stop multiplying and the body's defences can clear the infection. Used as eye drops or ointment, it acts mainly on the surface of the eye where the infection is, so very little is absorbed into the rest of the body. This local action is why the eye forms are considered safe for general use, while the rare blood problem is tied to the much higher exposure from the oral and injected forms.
Company & origin
Originated / developed by: Generic (long-established).
A broad antibiotic used in the UK mostly as eye drops or ointment to treat bacterial conjunctivitis, available from pharmacies.
Practical use
How to take Chloramphenicol
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- For eye drops, gently pull down the lower lid and place a drop into the pocket it forms, then blink to spread it, using the eye as often as directed.
- If using the ointment, apply a small amount inside the lower lid; it is often used at night, sometimes alongside drops in the day.
- Wash your hands before and after, and avoid letting the dropper or nozzle touch your eye or lashes.
- Do not wear contact lenses while your eye is infected or while using the treatment, and do not share the medicine with anyone else.
- Keep using it for the full course advised, often for a couple of days after the eye looks better, and discard the bottle after the period stated once opened.
Weighing it up
Advantages & disadvantages of Chloramphenicol
Advantages
- An effective and convenient treatment for bacterial conjunctivitis that is often available straight from a pharmacy.
- Acts mainly on the surface of the eye, so very little is absorbed into the rest of the body.
- Comes as both drops and ointment, which can be combined for daytime and overnight use.
Disadvantages
- Brief stinging or blurred vision after use is common, and the ointment can blur sight for a short while.
- Not suitable for every red eye, so a doctor or optician is needed if symptoms are severe or do not settle.
- The systemic (oral or injected) form carries a rare but serious blood-disorder risk and is reserved for severe infections.
Practical use
Good to know
For an infected, sticky eye, chloramphenicol eye drops or ointment are a reliable and convenient treatment you can usually get from a pharmacy. Wash your hands before and after using them, avoid touching the dropper or nozzle to your eye, and do not share the medicine or wear contact lenses while the eye is infected. Most simple conjunctivitis settles within a few days; see your doctor or optician if there is no improvement, if vision is affected, if there is significant pain or marked light sensitivity, or if the eye is severely red, as these can point to something more than a simple infection. Newborn babies should be assessed by a doctor rather than treated with over-the-counter drops. The serious bone-marrow effect that chloramphenicol is famous for is linked to the oral and injected forms used for severe infections and is very rare; it is not a feature of normal eye-drop treatment, though any new bruising, unusual bleeding or persistent sore throat during longer systemic use should be reported.
Who should not take it / use with caution
- People with a known allergy to chloramphenicol or previous serious blood problems with it should not use it.
- Newborn babies and very young infants should be assessed by a doctor rather than given over-the-counter eye drops.
- Anyone with eye pain, reduced vision, marked light sensitivity or a severely red eye should see a clinician before self-treating.
Monitoring
- Checking that the eye is improving within a few days and arranging review if it is not.
- Watching for signs of an allergic reaction around the eye, such as swelling, rash or worsening redness.
- For systemic use only, blood-count monitoring and prompt reporting of bruising, bleeding or sore throat.
Side effects
- Brief stinging, burning or itching of the eye and short-lived blurred vision after putting it in are common.
- Occasionally an allergic reaction with swelling, redness or a rash around the eye.
- With the systemic (oral or injected) form only, a rare but serious effect on the bone marrow, which is not a feature of normal eye-drop use.
Key interactions
- Eye drops and ointment are very unlikely to interact with tablets or other medicines because so little is absorbed.
- Other eye drops should be separated by a few minutes so each has time to work.
- The systemic form can interact with medicines such as warfarin and some diabetes and epilepsy treatments, which is one reason it is specialist-only.
Available as: Eye drops and eye ointment; also tablets, capsules and injection for specialist use.
Answers
Chloramphenicol: frequently asked questions
What is chloramphenicol used for in the UK?
Most often it is used as eye drops or ointment to treat bacterial conjunctivitis, an infected red sticky eye, and many products can be bought from a pharmacy.
Can I buy it without a prescription?
Yes, the eye drops and ointment can usually be bought from a pharmacy for adults and children over a certain age, after a brief check with the pharmacist.
Is it true it can harm the blood?
A rare but serious effect on the bone marrow is linked to the oral and injected forms used for severe infections, not to normal eye-drop use.
When should I see a doctor instead?
See a doctor or optician if there is eye pain, reduced vision, marked light sensitivity, a severely red eye, no improvement in a few days, or if a newborn is affected.
Can I wear my contact lenses while using it?
No. Avoid contact lenses while the eye is infected and while using the treatment, and follow your optician's advice about when to start wearing them again.
The wider class
About Chloramphenicol antibiotic
Chloramphenicol belongs to the chloramphenicol antibiotic class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF
- NICE CKS
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