What the FDA labels say about taking them together
Mefloquine and quinine
Mefloquine's FDA label of November 18, 2024 names quinine in its contraindications section, and quinine's label names mefloquine too. The mefloquine label: “CONTRAINDICATIONS Use of mefloquine hydrochloride tablets is contraindicated in patients with a known hypersensitivity to mefloquine or related compounds or to any of the excipients contained in the formulation.”
Check it at the source: the mefloquine FDA label on DailyMed (effective November 18, 2024, Chartwell RX, LLC); the quinine FDA label on DailyMed (effective November 9, 2023).
What does the mefloquine label say about quinine?
Mefloquine label, contraindicationsCONTRAINDICATIONS Use of mefloquine hydrochloride tablets is contraindicated in patients with a known hypersensitivity to mefloquine or related compounds (eg, quinine and quinidine) or to any of the excipients contained in the formulation.
Source: FDA drug label (Mefloquine Hydrochloride), Chartwell RX, LLC, effective November 18, 2024 (SPL set b884d22b-aae7-4f14-9a04-ae4029a229f0), via openFDA; the full label on DailyMed
What does the quinine label say about mefloquine?
Quinine label, contraindications (prescription label)CONTRAINDICATIONS Quinine sulfate is contraindicated in patients with the following: Prolongation of QT interval ( 4 ) Glucose-6-phosphate dehydrogenase (G6PD) deficiency ( 4 ) Myasthenia gravis ( 4 ) Known hypersensitivity to quinine, mefloquine, or quinidine ( 4 ) Optic neuritis ( 4 ) Quinine sulfate is contraindicated in patients with the following:
Quinine label, drug interactions (prescription label)Mefloquine In 7 healthy subjects who received mefloquine (750 mg) at 24 hours before an oral 600 mg dose of quinine sulfate, the AUC of mefloquine was increased by 22% compared to mefloquine alone.
Quinine label, warnings and precautions (prescription label)Concomitant administration of quinine sulfate with the antimalarial drugs, mefloquine or halofantrine, may result in electrocardiographic abnormalities, including QT prolongation, and increase the risk for torsades de pointes or other serious ventricular arrhythmias.
Source: FDA drug label (Chininum sulphuricum), Boiron, effective November 9, 2023 (SPL set 33885950-2a55-11e7-8288-424c58303031), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Mefloquine | Quinine | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $3.97 per tablet 250 mg tablet | $0.698 per capsule 324 mg capsule |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once