1. Clinical Overview
Artemether-Lumefantrine is a fixed-dose combination antimalarial medication, classified as an Artemisinin-based Combination Therapy (ACT). It is the first-line treatment for uncomplicated Plasmodium falciparum malaria in India and globally, as per WHO and National Center for Vector Borne Diseases Control (NCVBDC) guidelines. Artemether provides rapid parasiticidal action, reducing parasite biomass by up to 10,000-fold per asexual cycle, while lumefantrine, a longer-acting partner drug, eliminates residual parasites and prevents recrudescence.
| Onset | Duration | Bioavailability |
|---|---|---|
| Artemether: 2-4 hours; Lumefantrine: Variable, but synergistic effect starts within hours of first dose. | Artemether: 6-11 hours; Lumefantrine: 3-6 days. | Artemether: Variable, enhanced with fatty meals (up to 2-3 fold increase). Lumefantrine: Highly variable (4-11% in fasting state, increases up to 16-fold with a high-fat meal). |
2. Mechanism of Action
The combination exerts a rapid, multi-stage schizonticidal effect. Artemether acts quickly on the early trophozoite stage, while lumefantrine acts on the later stages. The combination targets the parasite's digestive vacuole and other organelles.
3. Indications & Uses
- Treatment of uncomplicated Plasmodium falciparum malaria
- First-line therapy for malaria in areas with chloroquine resistance (as per Indian National Drug Policy on Malaria)
4. Dosage & Administration
Adult Dosage: Standard 6-dose regimen over 3 days for patients ≥35 kg: Initial dose: 4 tablets (Artemether 60mg + Lumefantrine 360mg per tablet). Then, 4 tablets at 8, 24, 36, 48, and 60 hours after the first dose. Total: 24 tablets.
Administration: MUST be taken with food (e.g., milk, biscuit, chapati with ghee/oil) or a milk-based nutritional supplement to ensure adequate absorption, especially of lumefantrine. If vomiting occurs within 1 hour of dosing, a repeat dose should be taken. Tablets can be crushed for children. Complete the full 3-day course even if symptoms improve.
5. Side Effects
Common side effects may include:
- Headache
- Dizziness
- Anorexia
- Nausea
- Abdominal pain
- Diarrhea
- Cough
- Palpitations
- Prolonged QT interval on ECG (usually asymptomatic)
6. Drug Interactions
| Drug | Effect | Severity |
|---|---|---|
| Rifampicin | Markedly reduces plasma concentrations of both artemether and lumefantrine, leading to treatment failure. | Contraindicated |
| Ketoconazole, Itraconazole | May increase plasma concentrations of lumefantrine, potentially increasing risk of QT prolongation. | Major |
| Antiretroviral Protease Inhibitors (e.g., Lopinavir/ritonavir) | May increase lumefantrine levels; monitor for QT prolongation. | Major |
| Antiepileptics (Carbamazepine, Phenytoin, Phenobarbital) | Reduce plasma concentrations of artemether/lumefantrine, risk of treatment failure. | Contraindicated |
| Antiarrhythmics (Amiodarone, Flecainide), Antipsychotics, Antidepressants | Additive risk of QT interval prolongation. | Major |
| Grapefruit Juice | May inhibit CYP3A4, potentially increasing drug levels. | Moderate |
7. Patient Counselling
- DO take the medicine exactly as prescribed, completing the full 3-day course.
- DO take each dose with food or milk.
- DO inform your doctor if you are taking any other medicines, including herbal remedies.
- DO NOT take with grapefruit juice.
- DO NOT take if you are on rifampicin, certain anti-epileptics, or St. John's wort.
- DO NOT use for malaria prevention.
8. Toxicology & Storage
Overdose: Nausea, vomiting, dizziness, syncope, QT interval prolongation leading to ventricular arrhythmias (Torsades de pointes), convulsions. No specific experience with massive overdose.
Storage: Store below 30°C. Protect from moisture. Keep in the original blister pack until use. Keep out of reach of children.