Atovaquone + Proguanil is a combination medication primarily used for the prevention and treatment of malaria. It is sold under the brand name Malarone (and generics). Here’s an overview of its uses, mechanism of action, dosage, side effects, and precautions:
Uses of Atovaquone + Proguanil
1. Malaria Prevention (Prophylaxis):
- Used to prevent malaria in travelers visiting malaria-endemic regions.
- Effective against Plasmodium falciparum, including chloroquine-resistant strains.
2. Malaria Treatment:
- Used to treat acute, uncomplicated malaria caused by Plasmodium falciparum.
Mechanism of Action
- Atovaquone: Inhibits mitochondrial electron transport in the malaria parasite, disrupting its energy production.
- Proguanil: Metabolized to cycloguanil, which inhibits dihydrofolate reductase, an enzyme necessary for DNA synthesis in the parasite.
- The combination of the two drugs has a synergistic effect, enhancing their antimalarial activity.
Dosage of Atovaquone + Proguanil
1. For Prevention (Prophylaxis):
- Adults: 1 tablet (250 mg atovaquone + 100 mg proguanil) daily.
- Children: Dosage based on body weight.
- Start 1–2 days before entering a malaria-endemic area, continue daily during the stay, and for 7 days after leaving.
2. For Treatment:
- Adults: 4 tablets (250 mg atovaquone + 100 mg proguanil) once daily for 3 consecutive days.
- Children: Dosage based on body weight.
Side Effects of Atovaquone + Proguanil
Common side effects include:
- Headache
- Nausea, vomiting, or diarrhea
- Abdominal pain
- Dizziness
- Mild rash
Rare but serious side effects:
- Severe allergic reactions (e.g., swelling, difficulty breathing)
- Liver problems (e.g., jaundice, dark urine)
- Mouth sores or ulcers
Precautions of Atovaquone + Proguanil
1. Contraindications:
- Severe kidney impairment.
- Known hypersensitivity to atovaquone or proguanil.
2. Drug Interactions:
- Rifampin and rifabutin (reduce atovaquone levels).
- Metoclopramide (reduces atovaquone absorption).
- Warfarin (monitor INR closely).
3. Pregnancy and Breastfeeding:
- Use only if needed and the benefits outweigh the risks.
- Consult a healthcare provider.
4. Other Considerations:
- Not recommended for severe or complicated malaria.
- Ensure adequate food intake (especially fatty foods) to improve atovaquone absorption.
Effectiveness
- Highly effective for both prevention and treatment of malaria when used as directed.
- Resistance is rare but has been reported in some regions.
If you are considering or using this medication, consult a healthcare professional for personalized advice and dosing instructions.