Artemether + lumefantrine
Antimalarials
Antimalarials
The artemisinin combination used in Colombia for uncomplicated P. falciparum malaria; taken with fatty food or milk so lumefantrine is absorbed.
Quick facts
- Group
- Antimalarials
- Target
- Parasite heme (artemether is activated by heme iron; lumefantrine blocks heme detoxification)
- Used for
- Uncomplicated P · Uncomplicated P
- Key effects
- Headache and dizziness · Nausea · Tiredness
- Monitor
- Clinical response · Vomiting after a dose
- ATC
- P01BF01
No doses: the clinician sets them by the current guideline.
Mechanism of action
A fixed-dose combination of two blood schizonticides. Artemether, a derivative of artemisinin, is converted to dihydroartemisinin; its endoperoxide bridge is opened by heme iron inside the parasite and releases free radicals that damage parasite proteins, clearing ring stages to early schizonts fast and reducing gametocytes. Lumefantrine, an aryl-amino alcohol like quinine and mefloquine, is thought to stop the parasite turning toxic heme into inert pigment. Lumefantrine stays in the blood for days and kills the parasites that survive the short-lived artemether.
- Artemether becomes dihydroartemisinin
- Heme iron opens its peroxide bridge: radicals hit the parasite
- Lumefantrine blocks heme detoxification
- Long-acting lumefantrine kills the survivors
Indications
- Uncomplicated P. falciparum malaria (the ACT adopted in Colombia) Malaria →
- Uncomplicated P. vivax malaria where chloroquine resistance exists, and mixed infections Malaria →
- Oral follow-on course after parenteral artesunate for severe malaria Malaria →
Adverse effects
Common
- Headache and dizziness
- Nausea, vomiting and loss of appetite
- Tiredness, weakness, muscle and joint pain
- Trouble sleeping
Contraindications
- Hypersensitivity to artemether, lumefantrine or other artemisinin derivatives
- Not for malaria prevention
- Caution: congenital or acquired long QT, family history of sudden death, low potassium or magnesium
Key interactions
- Rifampicin and other strong CYP3A4 inducers
- Much lower artemether, dihydroartemisinin and lumefantrine levels: risk of treatment failure
- Ketoconazole and other CYP3A4 inhibitors; grapefruit
- Raise artemether and lumefantrine levels
- Hormonal contraceptives
- May be less effective; another method of contraception is needed
- Other QT-prolonging drugs (e.g. quinine)
- Additive QT prolongation
What is monitored
- Clinical response and parasite count on follow-up blood smears
- Vomiting after a dose (the dose may need repeating)
- ECG and potassium and magnesium in patients with heart disease or QT risk
- Signs of severe malaria that require a switch to parenteral artesunate
Administration and safety
- Oral, as a short course of fixed-dose tablets; given with fatty food or a milky drink to improve lumefantrine absorption.
- Tablets can be crushed and mixed with water for patients who cannot swallow them; dispersible paediatric tablets exist.
- If the patient vomits soon after a dose, the prescriber decides whether to repeat it.
- WHO and Colombia use a 3-day course; in 2026 CDC (USA) moved to a longer 5-day course after treatment failures, so local guidance is followed.
Pregnancy and breastfeeding
Colombia's guideline uses it in the second and third trimesters and quinine + clindamycin in the first; CDC states WHO now accepts it in all trimesters.
Nursing care
- Before: confirm the species by smear or rapid test, ask about pregnancy, heart disease and current medicines.
- Give each dose with food or milk and watch the patient swallow it; check for vomiting afterwards.
- Watch for danger signs (confusion, convulsions, dark urine, breathing difficulty): severe malaria needs parenteral treatment.
- Teaching: finish the full course even when the fever goes; use extra contraception during treatment; it does not prevent future infection.
Pharmacokinetics
- Absorption
- Oral; artemether peaks within about 2 hours; lumefantrine is very lipophilic and absorbed much better with fatty food or milk
- Distribution
- Lumefantrine is highly bound to plasma proteins
- Metabolism
- Artemether is converted mainly by CYP3A4 to active dihydroartemisinin; lumefantrine is metabolised in the liver by CYP3A4 to desbutyl-lumefantrine
- Elimination
- Artemether and dihydroartemisinin are cleared within hours; lumefantrine slowly
- Half-life
- Artemether: a few hours; lumefantrine: about 3 days
Test yourself
Think of the answer, then tap the question to see it.
Why must artemether + lumefantrine be taken with fatty food or milk?
Lumefantrine is highly lipophilic; fat greatly increases its absorption, and low levels risk treatment failure.
What role does each component play?
Artemether clears most parasites within hours; long-acting lumefantrine kills the remaining parasites and protects artemether from resistance.
Which antituberculosis drug lowers its levels markedly?
Rifampicin, a strong CYP3A4 inducer, lowers artemether, dihydroartemisinin and lumefantrine exposure.
What is added to it in Colombia for P. falciparum, and why?
A single low dose of primaquine, which sterilises gametocytes and reduces transmission to mosquitoes; G6PD testing is not required for that single dose.
Connections
← Back to the class: Antimalarials
Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Sources: Artemether and Lumefantrine: MedlinePlus Drug Information (MedlinePlus (U.S. National Library of Medicine), 2025); Adopción Parcial de Guía de Práctica Clínica Diagnóstico y tratamiento de la malaria, OMS 2022. Guía para Colombia, GPC #67-2022 (Ministerio de Salud y Protección Social (Colombia), 2022); Treatment of Uncomplicated Malaria (Centers for Disease Control and Prevention (CDC), 2026); Malaria in the United States: Treatment Tables (Centers for Disease Control and Prevention (CDC), 2026).
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Representative model, for educational purposes only.