Chloramphenicol is known as a broad-spectrum antibiotic, which means it is effective against infections caused by a wide variety of bacteria.
Chloramphenicol works by preventing bacteria from producing proteins that are essential to them. Without these proteins the bacteria cannot grow, replicate and increase in numbers. Chloramphenicol therefore controls the infection and remaining bacteria die or are killed by the body's immune system.
Chloramphenicol can potentially have side effects on the bone marrow, where blood cells are made. For this reason chloramphenicol is only used in the treatment of serious infections, for which other antibiotics are not working or not suitable.
This medicine should not be used if you are allergic to any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Just because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
The side effects listed above may not include all of the side effects reported by the medicine's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to make sure that the combination is safe.
Chloramphenicol can increase the levels of phenytoin, ciclosporin and tacrolimus in the blood. If you are taking one of these medicines it is important that the amount of the medicine in your blood is closely monitored while you are having treatment with chloramphenicol.
Chloramphenicol may enhance the anti-blood-clotting effect of warfarin. This may increase your blood clotting time (INR) and increase the risk of bleeding. Your INR should be checked more frequently if you are taking chloramphenicol capsules with warfarin. Your warfarin dose may need reducing while you are taking chloramphenicol capsules.
Chloramphenicol may also enhance the effect some anti-diabetic medicines known as sulfonylureas, such as gliclazide, glipizide or tolbutamide, and cause them to have a greater effect on lowering blood sugar levels (hypoglycaemia). Your blood sugar levels may need to be checked more frequently if you are taking chloramphenicol capsules and a sulfonylurea.
Rifampicin and phenobarbital can decrease the amount of chloramphenicol in the blood, making it less effective for treating infections.
There may be an increased risk of side effects if this medicine is used in combination with other medicines that can affect blood cell counts, for example the antipsychotic clozapine.
Oral typhoid vaccine (Vivotif) should not be taken until at least three days after you have finished a course of this antibiotic, because the antibiotic could make this vaccine less effective.
In the past, women using hormonal contraception such as the pill or patch would be advised to use an extra method of contraception (eg condoms) while taking an antibiotic like this one and for seven days after finishing the course. However, this advice has now changed. You no longer need to use an extra method of contraception with the pill, patch or vaginal ring while you take a course of antibiotics. This change in advice comes because to date there is no evidence to prove that antibiotics (other than rifampicin or rifabutin) affect these contraceptives. This is the latest guidance from the Faculty of Sexual & Reproductive Healthcare.
However, if you are taking the contraceptive pill and experience vomiting or diarrhoea as a result of taking this antibiotic, you should follow the instructions for vomiting and diarrhoea described in the leaflet provided with your pills.
Chloramphenicol capsules are only available generically (ie without a brand name).
Chloramphenicol ear drops and eye drops are also available.