Malarone (Atovaquone/Proguanil)

What is Malarone?

Malarone is a fixed-dose combination antimalarial medicine containing two active ingredients: Atovaquone (250 mg) and Proguanil hydrochloride (100 mg). Developed in the 1990s as an alternative to Chloroquine and Mefloquine, Malarone rapidly became a preferred choice for malaria prophylaxis among travellers to malaria-endemic regions.

The combination acts against P. falciparum, including resistant strains. Spanish AEMPS product information describes prevention and treatment of uncomplicated falciparum malaria, with different weight limits and schedules.

Malarone Pediátrico contains 62.5 mg atovaquone and 25 mg proguanil hydrochloride. Prevention covers 11–40 kg; its uncomplicated-malaria treatment indication covers 5 to under 11 kg. These limits must not be interchanged.

How does Malarone work?

Malarone’s efficacy against malaria comes from the synergistic action of its two components:

• Atovaquone: A hydroxynaphthoquinone that inhibits mitochondrial electron transport in Plasmodium parasites, disrupting the parasite’s ability to generate energy. Specifically, Atovaquone targets ubiquinol-cytochrome c oxidoreductase (cytochrome bc1 complex) — a component essential to parasite metabolism that is distinct in structure from its human counterpart, providing selective toxicity.
• Proguanil: A biguanide that is converted in the body to cycloguanil, which inhibits dihydrofolate reductase (DHFR), an enzyme essential for nucleotide synthesis and parasite replication. Proguanil also potentiates the mitochondrial membrane potential-disrupting effects of Atovaquone, making the combination more effective than either agent alone.

Crucially, Malarone provides causal prophylaxis — it acts against the liver-stage (hepatic schizont) forms of Plasmodium as well as blood-stage parasites. This is why only a 7-day post-travel course is required, rather than the 4-week course needed by drugs acting on blood stages only.

Who is Malarone for?

A doctor may consider Malarone after checking the destination and individual contraindications, for example for:

• Travellers to sub-Saharan Africa, South and Southeast Asia, Central and South America, and other high-risk malaria regions
• Travellers who cannot tolerate or have contraindications to Mefloquine (Lariam) or Doxycycline
• Short-trip travellers who benefit from the shorter pre- and post-travel dosing period
• Travellers to destinations where both Chloroquine and Mefloquine resistance is documented

For prevention, the following limits apply:

• Patients with severe renal impairment (creatinine clearance below 30 mL/min)
• Pregnant women (use only if essential and under close medical supervision)
• Breastfeeding women (Atovaquone levels in breast milk are unknown)
• Prevention below 11 kg is not established in the Spanish paediatric label; this does not exclude its distinct treatment indication

Dosage

For adults over 40 kg, the Spanish Malarone prevention schedule is:

Malarone should be taken at the same time each day with food or a milky drink — taking with food significantly improves Atovaquone absorption and reduces gastrointestinal side effects.

For children, Malarone Paediatric dosing is based on body weight and must be determined by a qualified medical professional.

Side effects

Very common effects

Headache, abdominal pain, nausea, vomiting and diarrhoea are listed as very common in the product information.

Common effects

Abnormal dreams, depression, insomnia, dizziness, rash and itching are common. Anaemia and raised liver enzymes are also listed; some frequencies derive from atovaquone studies with different populations and doses.

Serious reactions

Severe allergy, anaphylaxis, severe skin reactions and hepatitis have been reported. Some have unknown frequency, rather than a proven very rare rate. Stop and obtain immediate help for severe allergic or skin reactions. Do not drive if dizzy.

Malarone vs alternatives

Features relevant to assessment:

• Shorter post-travel course (7 days vs 4 weeks for Doxycycline and Lariam)
• Can be started just 1–2 days before travel (vs 2–3 weeks for Lariam in UKMEAG guidance)
• Effective against Chloroquine and Mefloquine-resistant strains

Treatment cost depends on the product and lawful supply route; this page does not establish a current price comparison.

Online assessment for Malarone (Atovaquone/Proguanil)

Prescrivia is a technology intermediary connecting patients with independent doctors and licensed pharmacies. We do not provide medical services, prescribe, employ doctors, sell or dispense medicines.

1. Assessment: Provide your symptoms or travel plans, medical history and all current medicines.
2. Independent review: A doctor decides whether a prescription is clinically appropriate; Prescrivia does not guarantee a prescription.
3. Dispensing: Any lawful dispensing is the responsibility of a licensed pharmacy, subject to the applicable rules and product availability.

In Spain, distance selling of prescription medicines is prohibited. An online assessment or a product label does not establish that a medicine can legally be supplied or delivered through this platform. This information does not change eligibility or fulfilment rules.

Important safety information

Do not take Malarone if you:

• Have severe kidney disease for prophylactic use (creatinine clearance below 30 mL/min)
• Have a known hypersensitivity to Atovaquone, Proguanil, or any excipient in the tablet
• Are pregnant, unless the potential benefit outweighs the risk and it is agreed by a doctor
• Are breastfeeding (the Spanish label says not to use during breastfeeding)

Tell your doctor if you:

• Have mild to moderate kidney impairment (the label requires no dose adjustment, but the doctor must assess kidney function)
• Are taking Rifampicin, Rifabutin, Metoclopramide, or Tetracyclines (can reduce Atovaquone plasma levels significantly)
• Are taking Warfarin or anticoagulants (Malarone may enhance anticoagulant effect)
• Have liver disease

If you vomit within 1 hour of taking a dose: Take another dose as soon as possible.

Interactions and resistance: Rifampicin, rifabutin and metoclopramide combinations are not recommended; avoid efavirenz or boosted protease inhibitors where possible. Warfarin requires monitoring when Malarone is started or stopped. Do not use this prevention table to treat established malaria or assume current susceptibility for your destination.

Sources

• AEMPS: Malarone 250 mg/100 mg, product information
• AEMPS: Malarone Pediátrico 62.5 mg/25 mg, product information
• BOE: Real Decreto Legislativo 1/2015, article 3.5

General information, not individual prescribing advice. Seek urgent care for fever during or after malaria-risk travel even after prevention. Continue mosquito-bite precautions.