Co-Trimoxazole is the active ingredient of Adco-Co-Trimoxazole, Bactrim, Bencole, Casicot, Cozole, Meditrim, Merck-Co-Trimoxazole, Micro-Co-Trimoxazole, Purbac, Sandoz Co-Trimoxazole, Septran and Trimethox.

General Information

Co-trimoxazole is an antibiotic that consists of a combination of two other antibiotics; trimethoprim and sulphamethoxazole. It is prescribed for treatment of urinary tract infections, respiratory tract infections, prostate infections, typhoid fever, cholera and acne, caused by susceptible organisms.

In years-gone-by co-trimoxazole was used extensively, but therapeutic effectiveness is decreasing as a result of bacterial resistance.

Gastro-intestinal side-effects, headache and nausea can be a result of both components of co-trimoxazole, while a skin rash, allergy and fever are less common. Allergic reactions are mostly the result of a sulphur allergy.

It is important to note that this medication is only effective against bacterial infections - if your infection is the result of a viral or fungal infection, it will be ineffective.

Antibiotic resistance - when bacteria develop the ability to defend themselves against the effect of an antibiotic - occurs frequently with many antibiotics. It mostly happens when patients do not complete the prescribed course in full, allowing bacteria to recover from treatment, and by using antibiotics for non-bacterial infections such as cold and flu.

How does co-Trimoxazole work?

Co-trimoxazole prevents bacterial DNA replication and transcription by inhibiting successive steps in bacterial folate synthesis.

Fast facts

Drug schedule: Schedule 4

Available as: Co-Trimoxazole is available as tablets, syrup and injection.

What does it do? Co-trimoxazole is an antibiotic.

Overdose risk: Medium

Dependence risk: Low

Is co-Trimoxazole available as a generic? Yes

Is co-Trimoxazole available on prescription only? No

User information

Onset of effect: Within 4 hours

Duration of action: Up to 12 hours

Dietary advice: This medication should be taken on an empty stomach; At least 8 glasses of water should be consumed every day while taking co-trimoxazole.

Stopping this medicine: Do not stop this medication until the prescribed dose has been completed; premature discontinuation may cause symptoms to recur.

Prolonged use: No problems expected; folic acid supplementation may be needed

Special precautions

Consult your doctor before using this drug if:

• you have epilepsy
• if you have liver or kidney disease
• if you have a history of CNS disorders
• if you suffer from Porphyria
• if you have a pre-existing blood disorder
• if you are allergic to any of the components in this drug
• if you are taking any other medication.

Pregnancy: Avoid. Potential risk to the foetus has been reported. Consult your doctor before use, or if you are planning to fall pregnant.

Breastfeeding: Avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.

Porphyria: Avoid. This medication may cause serious adverse effects. Consult your doctor before use.

Infants and children: This medication is safe for use in children at the recommended dose.

Elderly: Caution is advised in the elderly as side effects are more likely.

Driving and hazardous work: No special precautions need to be taken.

Alcohol: No special precautions need to be taken.

Possible side effects

Interactions

Drug interactions

Disease interactions

Consult your doctor before using this drug if you have epilepsy, liver or kidney disease, a history of CNS disorders, porphyria or if you are allergic to any of the components of this drug.

Overdose action

A small overdose is no cause for concern. In case of intentional large overdose, seek emergency medical attention. Symptoms may include nausea and confusion.

Recommended dosage

Adults: 160/ 800 mg (trimethoprim/sulphamethoxazole) 12 hourly. This may be increased to 240/1200 mg 12 hourly in severe infections.

Children 6 weeks to 5 moths: 20/100 mg 12 hourly;

Children 6 months to 5 years: 40/200 mg 12 hourly;

Children 6 - 12 years: 80/400 mg 12 hourly.