What the FDA labels say about taking them together
Alosetron and fluvoxamine
Alosetron's FDA label of March 23, 2026 names fluvoxamine in its contraindications section, and fluvoxamine's label names alosetron too. The alosetron label: “Use of Fluvoxamine Concomitant administration of LOTRONEX with fluvoxamine is contraindicated.”
Check it at the source: the alosetron FDA label on DailyMed (effective March 23, 2026, Legacy Pharma USA Inc.); the fluvoxamine FDA label on DailyMed (effective June 27, 2026, Zydus Pharmaceuticals USA Inc.).
What does the alosetron label say about fluvoxamine?
Alosetron label, contraindicationsUse of Fluvoxamine Concomitant administration of LOTRONEX with fluvoxamine is contraindicated.
Alosetron label, drug interactionsUse with fluvoxamine is contraindicated. ( 4.3 , 7.1 ) CYP3A4 inhibitors: Use with caution in combination due to increased exposure of alosetron.
Source: FDA drug label (LOTRONEX), Legacy Pharma USA Inc., effective March 23, 2026 (SPL set c216e967-436f-475a-8e6a-2ad11adc63af), via openFDA; the full label on DailyMed
What does the fluvoxamine label say about alosetron?
Fluvoxamine label, contraindicationsCONTRAINDICATIONS Coadministration of thioridazine, tizanidine, pimozide, alosetron, or ramelteon with fluvoxamine maleate extended-release capsules is contraindicated (see Warnings and Precautions [ 5.4 to 5.8 ] ).
Fluvoxamine label, drug interactionsOther Drugs Alosetron: See Contraindications ( 4 ), Warnings and Precautions ( 5.7 ), and Lotronex ® (alosetron) package insert.
Fluvoxamine label, warnings and precautionsFluvoxamine increased mean alosetron plasma concentrations (AUC) approximately 6-fold and prolonged the half-life by approximately 3-fold.
Fluvoxamine Maleate label (ANI Pharmaceuticals, Inc., August 4, 2025), contraindicationsCONTRAINDICATIONS Coadministration Coadministration of tizanidine, thioridazine, alosetron, or pimozide with Fluvoxamine Maleate Tablets is contraindicated [see Warnings and Precautions ( 5.4 , 5.5 , 5.6 , 5.7 )].
Fluvoxamine Maleate label (ANI Pharmaceuticals, Inc., August 4, 2025), warnings and precautionsBecause alosetron is metabolized by a variety of hepatic CYP drug metabolizing enzymes, inducers or inhibitors of these enzymes may change the clearance of alosetron.
Source: FDA drug label (Fluvoxamine Maleate, NDA021519), ANI Pharmaceuticals, Inc., effective August 4, 2025 (SPL set 7ecd83ec-88f5-4f85-9cc2-9068375d8820), via openFDA
Source: FDA drug label (Fluvoxamine maleate extended-release), Zydus Pharmaceuticals USA Inc., effective June 27, 2026 (SPL set 6c71d4f6-54b5-4d3a-8d2f-b7773c92c32e), 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
| Alosetron | Fluvoxamine | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $2.02 per tablet 0.5 mg tablet | $4.08 per capsule 100 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