Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ALDORIL 25 vs Artemether-Lumefantrine
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Combination of methyldopa, a centrally acting alpha-2 adrenergic agonist that reduces sympathetic outflow, and hydrochlorothiazide, a thiazide diuretic that inhibits sodium reabsorption in the distal convoluted tubule, reducing plasma volume.
Artemether is rapidly converted to dihydroartemisinin, which produces free radicals that damage parasite proteins and membranes. Lumefantrine inhibits heme detoxification in the parasite food vacuole.
Hypertension
Treatment of uncomplicated malaria due to Plasmodium falciparum,Treatment of chloroquine-resistant malaria
Oral: 1 tablet (hydrochlorothiazide 25 mg/methyldopa 250 mg) twice daily; increase as needed to max 2 tablets twice daily.
Oral, 4 tablets (each containing 20 mg artemether and 120 mg lumefantrine) at 0, 8, 24, 36, 48, and 60 hours (total 6 doses). For patients ≥35 kg, alternatively 4 tablets at 0, 8, 24, 36, 48, and 60 hours.
7-16 hours (terminal). In renal impairment, half-life may exceed 24 hours, requiring dose adjustment.
Artemether: terminal elimination half-life approximately 1–2 hours. Dihydroartemisinin: approximately 1–2 hours. Lumefantrine: terminal elimination half-life 4–5 days (range 2–6 days) in patients with uncomplicated malaria; prolonged half-life contributes to post-treatment prophylaxis but may lead to accumulation with repeated dosing.
Methyldopa is metabolized primarily via hepatic conjugation and renal excretion; hydrochlorothiazide is not significantly metabolized and is excreted unchanged in urine.
Artemether is metabolized by CYP3A4 to dihydroartemisinin. Lumefantrine is metabolized by CYP3A4.
Renal: ~85% unchanged. Biliary/fecal: ~15% as metabolites.
Primarily fecal (biliary) elimination of unchanged drug and metabolites; renal excretion is negligible (<1% for artemether and <0.1% for lumefantrine). Artemether is extensively metabolized by CYP3A4/5 to dihydroartemisinin, which is further glucuronidated and excreted in bile. Lumefantrine is metabolized by CYP3A4 to desbutyl-lumefantrine; both parent and metabolite are eliminated via feces.
Methyldopa: less than 10% bound to plasma proteins. Hydrochlorothiazide: ~70% bound to plasma proteins (primarily albumin).
Artemether: 95% bound to plasma proteins (primarily albumin and α1-acid glycoprotein). Dihydroartemisinin: 93% bound. Lumefantrine: >99% bound to high-density lipoproteins (HDL) and, to a lesser extent, to albumin and α1-acid glycoprotein.
Methyldopa: 0.3-0.6 L/kg (distributes widely, including CNS). Hydrochlorothiazide: 0.8-1.5 L/kg (distributes into extracellular fluid).
Artemether: Vd approximately 2–5 L/kg, indicating extensive tissue distribution. Dihydroartemisinin: Vd 0.5–1.5 L/kg. Lumefantrine: Vd extremely large, ranging from 10–30 L/kg (reported up to 31 L/kg), reflecting extensive tissue binding and accumulation in erythrocytes and organs (liver, lung, kidney).
Methyldopa: oral bioavailability ~25% (first-pass metabolism). Hydrochlorothiazide: oral bioavailability ~60-80%.
Oral bioavailability: Artemether is 30–40% due to extensive first-pass metabolism by CYP3A4/5 to dihydroartemisinin, which has 80% oral bioavailability. Lumefantrine has highly variable and food-dependent bioavailability; absorption increases 2–16 fold when taken with a high-fat meal. Bioavailability is approximately 5–10% in the fasted state and up to 85% when administered with fat-containing food. The combination is formulated to enhance lumefantrine absorption with a fixed ratio of artemether:lumefantrine 1:6.
GFR 30-50 m L/min: use with caution, reduce dose. GFR <30 m L/min: not recommended.
No dose adjustment required for mild to moderate renal impairment. Not studied in severe renal impairment (Cr Cl <30 m L/min); use with caution.
Child-Pugh A: no adjustment; Child-Pugh B or C: contraindicated due to methyldopa hepatotoxicity risk.
No dose adjustment for mild to moderate hepatic impairment (Child-Pugh A or B). Not studied in severe hepatic impairment (Child-Pugh C); avoid use.
Not established; avoid use in children.
Weight-based dosing: 5-<15 kg: 1 tablet per dose; 15-<25 kg: 2 tablets per dose; 25-<35 kg: 3 tablets per dose; ≥35 kg: 4 tablets per dose. Administer at 0, 8, 24, 36, 48, and 60 hours. Crush tablets if needed for children <5 kg.
Start at lowest dose (1 tablet daily); monitor for orthostatic hypotension, sedation, and electrolyte imbalance.
No specific dose adjustment required. Monitor for QT prolongation and electrolyte disturbances due to potential age-related decline in cardiac conduction.
None
None
May cause sedation, depression, positive direct Coombs test, hemolytic anemia, hepatotoxicity, fluid/electrolyte imbalance, and sensitivity reactions; monitor liver function, CBC, and electrolytes.
QT interval prolongation,Arrhythmias,Recrudescence of infection,Hypersensitivity reactions,Use in hepatic impairment
Hypersensitivity to methyldopa, hydrochlorothiazide, or sulfonamides; active hepatic disease; anuria; history of methyldopa-induced liver disorders.
Hypersensitivity to artemether or lumefantrine,Severe malaria,Pregnancy (first trimester) unless no other option
Avoid high-sodium foods to optimize antihypertensive effect. Limit alcohol intake. Do not consume large amounts of potassium-rich foods (e.g., bananas, oranges, spinach) unless advised by a healthcare provider, as hydrochlorothiazide can alter potassium levels.
High-fat meal increases absorption; grapefruit juice may increase lumefantrine levels; avoid concurrent use.
First trimester: Limited human data, but animal studies show no teratogenicity at therapeutic doses. Second and third trimesters: Associated with fetal hypotension, oligohydramnios, and renal dysfunction due to methyldopa component. Hydrochlorothiazide may cause fetal electrolyte imbalances.
FDA Pregnancy Category C. Artemether-lumefantrine is not recommended in the first trimester unless no alternative; animal studies show embryotoxicity at high doses. Second and third trimester: limited human data but appears safe; no increased risk of congenital malformations reported. Use only if benefit outweighs risk.
Methyldopa is excreted in breast milk with M/P ratio of approximately 0.2-0.5; hydrochlorothiazide M/P ratio ~0.5-0.6. Considered compatible with breastfeeding by AAP, but monitor infant for hypotension and electrolyte disturbances.
Both artemether and lumefantrine are excreted in breast milk in low amounts. M/P ratio: artemether ~0.3, lumefantrine ~0.5. Considered compatible with breastfeeding; no adverse effects observed in infants. Use caution if infant has G6PD deficiency due to theoretical risk of hemolysis.
No standard dose adjustment required, but increased plasma volume in pregnancy may necessitate higher doses of methyldopa. Monitor clinical response and adjust accordingly.
No dose adjustment required for uncomplicated malaria in second and third trimester. First trimester: avoid unless no alternative; use same weight-based dosing. Pharmacokinetic changes in pregnancy (increased volume of distribution, altered metabolism) do not mandate dose changes; standard 6-dose regimen over 3 days is recommended.
ALDORIL 25 is a fixed-dose combination of methyldopa (250 mg) and hydrochlorothiazide (25 mg). Monitor for hypotension, especially during initial therapy or with volume depletion. Methyldopa may cause a positive direct Coombs test and hemolytic anemia; discontinue if anemia develops. Hydrochlorothiazide can cause electrolyte imbalances, hyperglycemia, and hyperuricemia. Avoid use in patients with pheochromocytoma or active liver disease.
Monitor ECG for QTc prolongation; administer with fatty food to enhance absorption; avoid in patients with severe hepatic impairment; pregnancy category C; caution with CYP3A4 inhibitors or inducers.
Take this medication exactly as prescribed, usually once or twice daily.,Rise slowly from sitting or lying to prevent dizziness from low blood pressure.,Avoid alcohol, which can increase dizziness and drowsiness.,Report any signs of infection, unusual tiredness, or yellowing of skin/eyes.,Use sun protection as hydrochlorothiazide may increase sun sensitivity.,Do not use potassium supplements or salt substitutes without consulting your doctor.
Take with a high-fat meal or whole milk to improve absorption.,Complete the full 3-day course even if symptoms improve.,Seek medical attention for signs of severe malaria (e.g., altered consciousness, difficulty breathing).,Avoid grapefruit juice during treatment.,Use effective contraception if of childbearing potential.
No interactions on record
"Anagrelide, a phosphodiesterase 3 (PDE3) inhibitor used for thrombocythemia, and artemether, an antimalarial artemisinin derivative, both prolong the QT interval by inhibiting cardiac potassium channels (specifically IKr). Concurrent use may result in additive QTc prolongation, increasing the risk of Torsade de Pointes and other ventricular arrhythmias. This risk is particularly relevant in patients with electrolyte imbalances, bradycardia, or pre-existing cardiac disease."
"Acepromazine, a phenothiazine antipsychotic/antiemetic, inhibits cytochrome P450 3A4 (CYP3A4), the primary enzyme responsible for metabolizing the antimalarial artemether. Concomitant administration can lead to significantly reduced clearance of artemether, elevating its plasma concentrations. This may increase the risk of dose-dependent toxicities, including neurotoxicity (e.g., ataxia, seizures) and cardiotoxicity (e.g., QT prolongation)."
"Concomitant administration of thioridazine, a potent CYP2D6 inhibitor, with artemether, a substrate of CYP2D6, can significantly increase the serum concentration of artemether. This elevation may potentiate the antimalarial effect but also heightens the risk of artemether-related adverse effects such as QT prolongation and neurotoxicity. Clinically, this interaction warrants caution due to potential cardiotoxicity and altered drug exposure."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ALDORIL 25 vs Artemether-Lumefantrine, answered by our medical review team.
ALDORIL 25 is a Antihypertensive Combination that works by Combination of methyldopa, a centrally acting alpha-2 adrenergic agonist that reduces sympathetic outflow, and hydrochlorothiazide, a thiazide diuretic that inhibits sodium reabsorption in the distal convoluted tubule, reducing plasma volume.. Artemether-Lumefantrine is a Antimalarial that works by Artemether is rapidly converted to dihydroartemisinin, which produces free radicals that damage parasite proteins and membranes. Lumefantrine inhibits heme detoxification in the parasite food vacuole.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ALDORIL 25 and Artemether-Lumefantrine depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ALDORIL 25 is: Oral: 1 tablet (hydrochlorothiazide 25 mg/methyldopa 250 mg) twice daily; increase as needed to max 2 tablets twice daily.. The standard adult dose of Artemether-Lumefantrine is: Oral, 4 tablets (each containing 20 mg artemether and 120 mg lumefantrine) at 0, 8, 24, 36, 48, and 60 hours (total 6 doses). For patients ≥35 kg, alternatively 4 tablets at 0, 8, 24, 36, 48, and 60 hours.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between ALDORIL 25 and Artemether-Lumefantrine in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. ALDORIL 25 is classified as Category C. First trimester: Limited human data, but animal studies show no teratogenicity at therapeutic doses. Second and third trimesters: Associated with fetal hypotension, oligohydramnios. Artemether-Lumefantrine is classified as Category C. FDA Pregnancy Category C. Artemether-lumefantrine is not recommended in the first trimester unless no alternative; animal studies show embryotoxicity at high doses. Second and thir. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.