Chlorsig / Chloramphenicol2020-05-10T17:52:59+10:00
  • Eye drops - all you need to know.

Chlorsig / Chloramphenicol

Chlorsig eye drops or eye ointment are the most popular forms of chloramphenicol.

Chlorsig or Chloramphenicol eye drops (or eye ointment) is a broad spectrum antibiotic used to treat a range of eye infections. It is available in the form of eye drops and ointment. Unfortunately it is grossly overused. This has only become worse since it became available over the counter.

Most eye irritations are not caused by bacterial infections. Most conjunctivitis is due to allergy, dryness or viral eye infections, none of which will respond to this medication.

When is Chlorsig indicated?

If you have been diagnosed with a bacterial eye infection that is not related to contact lens wear, this medication is a good choice. Why? Because it’s effective against a broad range of bacteria. It is also a good choice if you have a scratch on your eye that needs to be protected from possible infection. This is called prophylactic use. It’s also used after eye operations to protect the eye from harmful pathogens.

Chlorsig eye drops or ointment?

If the eye has been scratched, e.g. by a branch or a baby’s fingernail, your optometrist may prescribe Chloramphenicol ointment (rather than drops). This is because it is also an excellent lubricant and will prevent your eyelid from sticking to the surface of your eye while you sleep. It will also protect the eye against any bacterial infection.

When are these eye drops and ointment NOT indicated?

If you don’t have a bacterial infection in your eye, then Chlorsig will not help. Chances are, even if you have an eye infection, it may have a viral (or fungal) cause. Most irritations are not infections at all, and are as a result of inflammation. This may be autoimmune (such as in the case of acute inflammation like uveitis). Or it may be an allergic reaction to pollen or grasses. Dry Eyes also cause redness and inflammation and will not respond to this type of eye drop. In fact, these eye drops are preserved, and this preservative makes the irritation and inflammation worse.

If you have DRY, IRRITATED eyes, download our free eBook for more information on the most successful treatment.

Chloramphenicol side effects: Aplastic anaemia risk

Chloramphenicol is the active ingredient used in Chlorsig eye drops and eye ointment. This drug is also taken orally or injected for serious bacterial infections, when others have failed. In the USA, Chlorsig eye drops are NOT prescribed. Why not? Because the active ingredient, chloramphenicol, can rarely cause a serious systemic condition. This is called aplastic anaemia and is very rare. But the studies show that it is the high-dose oral form of the drug that can cause this disease. In Chlorsig eye drops, the active ingredient is very dilute.

It is considered harmless by hundreds of thousands of doctors in other countries including Australia and the UK.
If these eye drops did cause aplastic anaemia, we would expect to see a lot more of this disease in Australia and the UK, where it is used a lot. This is NOT the case. In fact, there is no difference in the incidence of aplastic anaemia between Australia and the USA. This is even though at least 5 million bottles of these eye drops are sold every year.

Now the most important point!!

Chlorsig eye drops and ointment should not be used as a treatment for any contact lens-related red eyes. Ever! 70% of these infections are caused by a nasty bacteria called pseudomonas. (See contact lens-related pseudomonas keratitis). This eye condition does not respond to chloramphenicol eye drops or ointments. There are cases of eyes going blind because of inappropriate use of this drug when contact lenses are involved.

Chlorsig over the counter: how to avoid unnecessary use of chloramphenicol eye drops

Avoid using over-the-counter Chlorsig unless you have been specifically advised to get it by your therapeutically-qualified optometrist or ophthalmologist.

If you have a red, irritated, inflamed eye, where possible see an eye care practitioner rather than a GP. Eye care practitioners (optometrists and ophthalmologists) have special equipment to examine your eyes under high magnification and adequate light. These are called Slit-Lamp Bio-microscopes. They can observe classic signs that help them decide what’s causing the problem. Is it a bacterial infection? Or, another, non-bacterial infection (such as a virus) or a non-infective cause?

Chlorsig for stye

We’ve written about stye on another page. While Chlorsig ointment won’t make a stye go away, it doesn’t do any harm and can actually be beneficial. – If the stye breaks, releasing pus onto the surface of the eye, Chlorsig can help prevent possible bacterial conjunctivitis.


95% of red eyes are not bacterial conjunctivitis. Red eyes have many other causes and rarely in an adult is Chlorsig indicated for a red eye.

Interestingly, children are much more likely to have bacterial infection of the eyes. This is due to an undeveloped immune system. It is thus more likely that Chlorsig is indicated in the younger population.
Where possible, choose an optometrist who is therapeutically qualified. Not only will they have had in-depth training in distinguishing between different eye diseases, but they will also be able to prescribe the appropriate eye drops to treat your eyes.
Worried about your eyes? Give us a call on (02) 9290 1899 or book an appointment with one of our therapeutically qualified optometrists.

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