Lumefantrine and Hydroxychloroquine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Lumefantrine
No brand names on recordHydroxychloroquine
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased risk of QT interval prolongation
Interaction Deep Dive
Hydroxychloroquine has been associated with QT interval prolongation1, ventricular premature contractions and torsades de pointes 3. Hydroxychloroquine is not recommended in patients taking other drugs that have the potential to prolong the QT interval 1 or are arrhythmogenic 1 as life-threatening additive effects on the QT interval, including torsades de pointes, has been reported 4. Correct electrolyte imbalances prior to use, monitor cardiac function as clinically indicated during hydroxychloroquine therapy. Discontinue hydroxychloroquine if cardiotoxicity is suspected or demonstrated by tissue biopsy 2.
Why it happens (mechanism)
Additive QT interval prolongation
Literature reports
4 reports — tap to read
a) In an observational study in patients who were treated with hydroxychloroquine with or without azithromycin for COVID-19, those who received both medications had significantly larger increase in QTc (+23 msec) compared with those who received hydroxychloroquine only (+5.5 msec). One patient who received both hydroxychloroquine and azithromycin developed torsades de pointes. Patients who received hydroxychloroquine alone had significantly longer baseline QTc (474 msec) compared with those who received hydroxychloroquine and azithromycin (442 msec). The majority of patients had 1 or more cardiovascular comorbidities and were taking at least 2 concomitant QTc-prolonging agents. Note that COVID-19 itself may predispose patients to risk of myocarditis or cardiomyopathy 4.
b) In a case series of patients with COVID-19, patients who received hydroxychloroquine alone had significantly lower rate of QTc increase of 500 msec or greater (5%) compared with those who received hydroxychloroquine with azithromycin (33%). Half of the patients were also receiving other agents with potential to prolong QT interval. Overall, most patients had some increase in QTc during therapy; no arrhythmias or cases of torsades de pointes were reported 5.
c) Hydroxychloroquine-associated QT interval prolongation was reported in a 41-year-old woman with congestive heart failure with systolic left ventricular dysfunction. Her comorbidities included hypertension, systemic lupus erythematosus, and stage 5 chronic kidney disease. One week after reinitiation of hydroxychloroquine therapy, a significant prolongation of the QT interval (QTc 614 msec) was observed during a routine ECG. Following treatment discontinuation of hydroxychloroquine, serial ECGs demonstrated a shortening of the QTc interval. The patient's QTc was 473 msec at a follow up 1 year after discharge 6.
d) QT prolongation and refractory ventricular arrhythmia were reported with chronic hydroxychloroquine use in a 67-year-old woman with systemic lupus erythematosus. The patient had been receiving prednisoLONE, theophylline, and hydroxychloroquine 200 mg/day for 1 year. The patient had a medical history of cirrhosis, hepatitis B virus related hepatoma with protal vein thrombosis, and asthma. The patient experienced a sudden episode of unconsciousness and generalized rigidity while at home. Although the patient regained consciousness within minutes and had no complaints of chest pain, palpitation, limb weakness, incontinence, or confusion, the episode recurred several times. Upon admission the ECG showed multiple ventricular premature contractions, torsades de pointes, and prolongation of the QT interval. Treatment with hydroxychloroquine was discontinued. Following medical management, ventricular arrhythmia subsided after 4 days and the QT interval shortened 3.
Common questions
Can I take Lumefantrine and Hydroxychloroquine together?
Increased risk of QT interval prolongation Always confirm with your pharmacist or prescriber before making any change.
How serious is the Lumefantrine and Hydroxychloroquine interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Lumefantrine or Hydroxychloroquine need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (6)
- Product Information: PLAQUENIL(R) oral tablets, hydroxychloroquine sulfate oral tablets. Concordia Pharmaceuticals Inc (per FDA), Kansas City, MO, 2021. DailyMed
- Product Information: SOVUNA(R) oral tablets, hydroxychloroquine sulfate oral tablets. ANI Pharmaceuticals, Inc. (per FDA), Baudette, MN, 2024. DailyMed
- Chen CY, Wang FL, & Lin CC: Chronic hydroxychloroquine use associated with QT prolongation and refractory ventricular arrhythmia. Clin Toxicol (Phila) 2006; 44(2):173-175. DOI
- Mercuro NJ, Yen CF, Shim DJ, et al: Risk of QT interval prolongation associated with use of hydroxychloroquine with or without concomitant azithromycin among hospitalized patients testing positive for coronavirus disease 2019 (COVID-19). JAMA Cardiol 2020; 5(9):1036-1041. PubMed
- Bessiere F, Roccia H, Deliniere A, et al: Assessment of QT intervals in a case series of patients with coronavirus disease 2019 (COVID-19) infection treated with hydroxychloroquine alone or in combination with azithromycin in an intensive care unit. JAMA Cardiol 2020; 5(9):1067-1069.
- Morgan ND, Patel SV, & Dvorkina O: Suspected hydroxychloroquine-associated QT-interval prolongation in a patient with systemic lupus erythematosus. J Clin Rheumatol 2013; 19(5):286-288. PubMed
Keep reading about Lumefantrine
Keep reading about Hydroxychloroquine
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