Lumefantrine (Coartem/Riamet)

What lumefantrine (only marketed combined with artemether) is and how it works

Lumefantrine is an antimalarial medicine that is only ever combined with a second antimalarial, artemether, in a single tablet. This combination (Coartem or Riamet) is used to treat acute, uncomplicated malaria caused by Plasmodium falciparum, the most dangerous type of malaria parasite. Artemether acts quickly to reduce the parasite level, while lumefantrine stays in the body longer to help clear the infection completely and reduce the risk of the parasite becoming resistant. (1)

This medicine must be taken with food -- taking it on an empty stomach can mean the medicine is not absorbed properly, and the malaria may not be fully treated. It can also affect the heart's electrical rhythm (QT interval), so tell your care team about any heart rhythm problems or other medicines you take before starting.

Mechanism of action: how lumefantrine (only marketed combined with artemether) works

Artemether is rapidly converted to the active metabolite dihydroartemisinin and acts quickly against blood-stage parasites; lumefantrine has a much longer elimination half-life and clears residual parasites, reducing recrudescence and resistance risk. Both components require adequate lipid intake for optimal oral bioavailability. (1)

What lumefantrine (only marketed combined with artemether) is used for

Before taking lumefantrine (only marketed combined with artemether)

Do not take / not appropriate for

• Do not take if you have a known allergy to artemether, lumefantrine, or any ingredient in the tablet. (all countries) (1)
• Do not take together with strong CYP3A4-inducing medicines, including rifampin, carbamazepine, phenytoin, or St. John's wort -- these can make the treatment less effective. (all countries) (1)
• Do not take halofantrine within one month of this medicine, because the combined effect on heart rhythm (QT interval) can be dangerous. (all countries) (1)
• Avoid if you have congenital long QT syndrome, a family history of sudden cardiac death, uncorrected low potassium or magnesium levels, or if you take other medicines that affect heart rhythm, unless your clinician judges the malaria treatment benefit outweighs this risk. (all countries) (1)

Tell your clinician about

• Any personal or family history of heart rhythm problems, including long QT syndrome or sudden cardiac death.
• All other medicines you take, especially anything that affects heart rhythm, HIV antiretroviral medicines, and any recent use of quinine or halofantrine.
• Whether you are able to eat food around the time of each dose -- this medicine must be taken with food to work properly.
• Whether you are pregnant, planning pregnancy, or breastfeeding.

How to take lumefantrine (only marketed combined with artemether)

• Always take each dose with food -- fat in food greatly increases how much of this medicine your body absorbs (up to about 16-fold for lumefantrine), and taking it without food can mean the malaria is not fully treated.
• Follow the exact dosing schedule given to you: an initial dose, then further doses at set time points over about 3 days (60 hours) -- do not skip or reschedule doses without your care team's guidance, since completing the exact course matters for curing the infection and preventing resistance.
• If you are prescribed quinine after finishing this medicine, tell that prescriber, since lumefantrine stays in the body for a long time and close heart-rhythm (ECG) monitoring may be advised.

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6)

Missed dose

Contact your prescriber or care team as soon as possible if a dose is missed or delayed -- completing this specific 6-dose schedule correctly and on time matters for curing the malaria infection and reducing resistance risk, so do not simply skip or take an extra dose on your own.

Overdose

Seek urgent medical attention if too much of this medicine has been taken, or if you notice an irregular or fast heartbeat, severe dizziness, or fainting, since this medicine can affect heart rhythm. (1)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Serious warnings

Interactions

• Strong CYP3A4-inducing medicines (rifampin, carbamazepine, phenytoin, St. John's wort) can make this medicine less effective and must not be combined with it. (1)
• CYP3A4-inhibiting medicines can raise levels of this medicine and increase the risk of heart-rhythm effects -- combine only with caution and medical guidance. (1)
• This medicine inhibits CYP2D6, which can raise the levels and effects (including cardiac effects) of other medicines broken down by that enzyme. (1)
• Halofantrine must not be taken within one month of this medicine because of additive heart-rhythm (QT-prolongation) risk. (1)
• If quinine is given after this medicine, close heart-rhythm (ECG) monitoring is advised because of lumefantrine's long elimination half-life. (3)
• Caution is advised with antiretroviral (HIV) medicines -- discuss with your care team if you are on HIV treatment. (1)

Pregnancy, breastfeeding, kidney/liver function, age

Monitoring

Before starting

• Personal/family history of heart-rhythm problems
• Current medicines, especially CYP3A4/CYP2D6-interacting and QT-affecting medicines
• Ability to take the medicine with food
• Pregnancy/breastfeeding status

During treatment

• Watch for palpitations, irregular heartbeat, severe dizziness, or fainting.
• Confirm each dose is taken with food.
• Watch for malaria symptoms continuing or returning after the course finishes, which may indicate treatment failure.

Storage

Store tablets as directed on the product packaging, typically at room temperature, away from moisture and out of reach of children.

Frequently asked questions

References

1. COARTEM (artemether and lumefantrine) tablets -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information, Novartis · United States · accessed 2026-07-30 · source 1
2. Confirmation that lumefantrine is never marketed as a standalone monotherapyPeer-reviewed pharmacology/clinical literature (multiple independent sources) · Global · accessed 2026-07-30 · source 2
3. Riamet 20 mg/120 mg Tablets -- Summary of Product Characteristicselectronic medicines compendium (emc), United Kingdom, Novartis · United Kingdom · accessed 2026-07-30 · source 3
4. Artemether/lumefantrine -- list of nationally authorised medicinal products, PSUSA/00000236European Medicines Agency (EMA), list of nationally authorised medicinal products · European Union · accessed 2026-07-30 · source 4
5. COARTEM artemether/lumefantrine 20 mg/120 mg tablet -- ARTG entries 298287 / 158527Therapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-30 · source 5
6. Riamet (artemether/lumefantrine) -- historical New Zealand approval, product no longer availableMedsafe (New Zealand regulator) -- secondary confirmation of historical approval and current unavailability · New Zealand · accessed 2026-07-30 · source 6
7. No confirmed Health Canada Drug Product Database entry located for Coartem/RiametN/A -- absence-of-evidence note, not a positive source · Canada · accessed 2026-07-30 · source 7

Brand names by country

Single-ingredient lumefantrine (only marketed combined with artemether) names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries