Drug Interaction Report

Chloroquine and Sultopride: Interaction Details

A pharmacist-reviewed analysis of the Chloroquine and Sultopride interaction: the documented clinical effects, severity rating, onset, mechanism, and management considerations, with cited references throughout.

AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature

Chloroquine

Aralen®
+

Sultopride

No brand names on record
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Dr. Brian Staiger, PharmD, BCPS
Updated Aug 8, 2026
Editorial policy · Data sources
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Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
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.

Of 332 documented Chloroquine interactions, 294 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
Onset
unspecified
Evidence
theoretical
Severity
Major

What happens

An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest)

Interaction Deep Dive

Chloroquine has been shown to prolong the QTc interval at the recommended therapeutic dose and an additive effect would be anticipated if administered with other agents which lengthen the QT interval5. Several antipsychotic agents have demonstrated QT prolongation including haloperidol 1, risperidone 2, sertindole 3, sultopride 6, and zotepine 7.

Why it happens (mechanism)

Additive effect on QT prolongation

Literature reports

1 report — tap to read

a) Sometimes fatal QRS prolongation and QTc prolongation have been reported in patients taking risperidone therapeutically 24.

Common questions

Can I take Chloroquine and Sultopride together?

An increased risk of cardiotoxicity (QT prolongation, torsades de pointes, cardiac arrest) Always confirm with your pharmacist or prescriber before making any change.

How serious is the Chloroquine and Sultopride 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 "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.

Questions for your pharmacist

  • Does my dose of Chloroquine or Sultopride 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 (7)

  1. O'Brien JM, Rockwood RP, & Suh KI: Haloperidol-induced torsade de pointes. Ann Pharmacother 1999; 33(10):1046-1050. DOI
  2. Duenas-Laita A, Castro-Villamor MA, Martin-Escudero JC, et al: New clinical manifestations of acute risperidone poisoning (letter). Clin Toxicol 1999; 37(7):893-894. PubMed
  3. Agelink MW, Zeit T, Baumann B, et al: In vivo cardiovascular effects of the new atypical neuroleptic sertindole. Int J Psychiatry Clin Pract 2001; 5:33-40. DOI
  4. Ravin DS & Levenson JW: Fatal cardiac event following initiation of risperidone therapy. Ann Pharmacother 1997; 31:867-870. PubMed
  5. Product Information: Aralen(R), chloroquine phosphate. Sanofi Pharmaceuticals, New York, NY, 2001. DailyMed
  6. Lande G, Drouin E, Gauthier C, et al: effects of sultopride chlorhydrate: clinical and cellular electrophysiological correlation. Ann Fr Anesth Reanim 1992; 11:629-635.
  7. Sweetman S (Ed): Martindale: The Complete Drug Reference. London: Pharmaceutical Press. Electronic version, MICROMEDEX, Greenwood Village, Colorado, Edition expires 06/2004.
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Chloroquine

Keep reading about Chloroquine

All Chloroquine interactions (332) Chloroquine drug information
Also serious with: Levomethadyl Pimozide Mesoridazine Levoketoconazole
Sultopride

Keep reading about Sultopride

All Sultopride interactions (44)
Also serious with: Goserelin Implant Sertraline Dasatinib Oxaliplatin Injection
Beyond drug–drug

These medications also interact with supplements

Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:

Chloroquine + Activated Charcoal Hibiscus Sabdariffa Biofeedback Coffee Charcoal Dendrobium European Mandrake Fever Bark Ginkgo + 21 more

major · moderate · minor — check everything you take with our drug–supplement interaction checker.

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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.