Atovaquone

How it works

It inhibits the parasite cytochrome bc1 complex, disrupting mitochondrial electron transport and pyrimidine synthesis.

Prescribing in practice

• Absorption is poor and significantly increased by fatty food, so it should be taken with food to ensure efficacy.
• It is an alternative in patients intolerant of co-trimoxazole for Pneumocystis pneumonia, generally in milder disease.
• Plasma concentrations may be reduced by interacting drugs such as rifampicin, potentially compromising efficacy.

Monitoring

Monitor clinical response and, where relevant, ensure adequate absorption by confirming it is taken with food.

Counselling the patient

• Always take with a fatty meal to help your body absorb the medicine.
• Report worsening breathlessness, fever or cough.
• Do not stop preventive treatment without advice.

Evidence & guidelines

Atovaquone is recommended as an alternative agent for Pneumocystis jirovecii pneumonia and, with proguanil, for malaria in current guidance.