What the FDA labels say about taking them together
Metaxalone and oliceridine
Oliceridine's FDA label of December 31, 2025 names metaxalone in its drug interactions section; the metaxalone labels PlainMeds reads (2) do not name oliceridine. The oliceridine label: “The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome.”
Check it at the source: the metaxalone FDA label on DailyMed (effective January 11, 2023, Amneal Pharmaceuticals of New York LLC); the oliceridine FDA label on DailyMed (effective December 31, 2025, Trevena, Inc.).
What does the metaxalone label say about oliceridine?
Metaxalone's label (effective January 11, 2023) and its 1 other brand-application label do not name oliceridine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Metaxalone), Amneal Pharmaceuticals of New York LLC, effective January 11, 2023 (SPL set f06f2b96-3684-483c-89f7-6c9201fd4664), via openFDA; the full label on DailyMed
What does the oliceridine label say about metaxalone?
Oliceridine label, drug interactionsClinical Impact: The concomitant use of opioids with other drugs that affect the serotonergic neurotransmitter system has resulted in serotonin syndrome. … neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), certain muscle relaxants (i.e., cyclobenzaprine, metaxalone), monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue). …
Source: FDA drug label (OLINVYK), Trevena, Inc., effective December 31, 2025 (SPL set ce167984-8b9d-40b7-84ce-d0f33fff1eaa), 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
| Metaxalone | Oliceridine | |
|---|---|---|
| Labeled for | Muscle spasms and spasticity | Pain |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.452 per tablet 800 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