What the FDA labels say about taking them together
Alosetron and apomorphine
Apomorphine's FDA label of February 24, 2022 names alosetron in its contraindications section; the alosetron label PlainMeds reads does not name apomorphine. The apomorphine label: “… apomorphine hydrocloride with 5HT 3 antagonists including antiemetics and alosetron, is contraindicated.”
Check it at the source: the alosetron FDA label on DailyMed (effective March 23, 2026, Legacy Pharma USA Inc.); the apomorphine FDA label on DailyMed (effective February 24, 2022, TruPharma, LLC).
What does the alosetron label say about apomorphine?
Alosetron's label (effective March 23, 2026) does not name apomorphine in these sections. A label lists what its studies and reports found; it is not a complete list.
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 apomorphine label say about alosetron?
Apomorphine label, contraindicationsCONTRAINDICATIONS Apomorphine hydrocloride is contraindicated in patients: Using concomitant drugs of the 5HT 3 antagonist class including antiemetics (e.g., ondansetron, granisetron, dolasetron, palonosetron) and alosetron [see Drug Interactions (7.1) ].
Apomorphine label, drug interactionsDRUG INTERACTIONS Concomitant use of antihypertensive medications and vasodilators: increased risk for hypotension, myocardial infarction, pneumonia, falls, and injuries ( 7.2 ) Dopamine antagonists such as neuroleptics or metoclopramide, may diminish the effectiveness of apomorphine hydrocloride ( 7.4 ) 7.1 5HT 3 Antagonists Based on reports of profound hypotension and loss of consciousness when apomorphine hydrocloride was administered with ondansetron, the concomitant use of apomorphine hydrocloride with 5HT 3 antagonists including antiemetics (for example, ondansetron, granisetron, dolasetron, palonosetron) and alosetron, is contraindicated.
Source: FDA drug label (Onapgo, NDA214056), MDD US Operations, LLC, a subsidiary of Supernus Pharmaceuticals, Inc, effective July 10, 2026 (SPL set f3552b6e-5ae7-4993-aa1a-e399c4a7080a), via openFDA
Source: FDA drug label (apomorphine hydrocloride), ANDA212025 (Tp Anda Holdings), as published by TruPharma, LLC, effective February 24, 2022 (SPL set aedf70e4-1949-44bc-bf1b-0f282c4f0705), 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 | Apomorphine | |
|---|---|---|
| Labeled for | n/a | Parkinson's disease |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $2.02 per tablet 0.5 mg tablet | n/a |
| 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