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Antiparasitic / Antifungal — PCP Prophylaxis / Treatment / Malaria Pregnancy: Use with caution — limited data; co-trimoxazole (2nd trimester) or pentamidine preferred for PCP in pregnancy; Malarone not recommended in pregnancy — use alternative malaria prophylaxis

Atovaquone

Brand names: Wellvone, Malarone (combined with proguanil)

Adult dose

Dose: PCP treatment (mild-moderate, sulfonamide intolerant): 750 mg twice daily × 21 days with food; PCP prophylaxis: 750 mg once daily with food; Malaria treatment (Malarone): atovaquone 1 g + proguanil 400 mg once daily × 3 days
Route: Oral
Frequency: Twice daily (treatment); once daily (prophylaxis/malaria)
Max: 1500 mg/day (PCP treatment)
Must be taken with food — particularly fatty food (increases absorption 3–4×). Oral suspension available (750 mg/5 mL). PCP: less effective than co-trimoxazole for moderate-severe disease but well-tolerated alternative. Malarone (combined): standard malaria prophylaxis and treatment — start 1–2 days before travel, continue 7 days after return.

Paediatric dose

Dose: PCP prophylaxis: 30 mg/kg once daily (max 1500 mg) mg/kg
Route: Oral suspension
Frequency: Once daily (prophylaxis)
Max: 1500 mg/day
BNFc: Malarone paediatric tablets (62.5 mg atovaquone + 25 mg proguanil) — weight-based dosing for malaria prophylaxis/treatment; PCP prophylaxis — suspension used in immunocompromised children

Dose adjustments

Renal

Use with caution in severe renal impairment — limited data; co-trimoxazole preferred if tolerated

Hepatic

Use with caution in severe hepatic impairment

Paediatric weight-based calculator

BNFc: Malarone paediatric tablets (62.5 mg atovaquone + 25 mg proguanil) — weight-based dosing for malaria prophylaxis/treatment; PCP prophylaxis — suspension used in immunocompromised children

Clinical pearls

  • Food requirement is critical for adequate absorption — specifically fatty food increases bioavailability from ~23% to 47%; if patient cannot eat, consider alternative (IV co-trimoxazole)
  • Metoclopramide interaction: significantly reduces atovaquone levels — avoid; use ondansetron or domperidone for nausea management during atovaquone therapy
  • Malarone malaria prophylaxis advantage: only 7-day post-travel course needed vs 4 weeks for mefloquine/doxycycline (atovaquone-proguanil only needs to cover liver phase for P. vivax/ovale — not active against hypnozoites — but P. falciparum lacks hypnozoite stage)
  • Rifampicin: absolutely avoid — halves atovaquone levels; use alternative in TB/MAC co-treatment

Contraindications

  • Severe renal impairment (relative — limited data)
  • Hypersensitivity to atovaquone

Side effects

  • Rash (very common)
  • GI disturbance (nausea, diarrhoea, vomiting)
  • Headache
  • Elevated LFTs
  • Hyponatraemia
  • Anaemia

Interactions

  • Rifampicin — reduces atovaquone levels by 50% (avoid)
  • Metoclopramide — reduces atovaquone levels (avoid concurrent use; use alternative antiemetic)
  • Tetracycline — reduces atovaquone levels (30% reduction)
  • Warfarin — enhanced anticoagulant effect

Monitoring

  • LFTs
  • Renal function
  • Rash monitoring
  • Clinical response (serial LDH in PCP — marker of treatment response)

Reference: BNFc; BNF 90; BHIVA HIV Guidelines; PHE Malaria Guidelines; NICE Malaria Prevention Guidance; IDSA PCP Guidelines. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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