What the FDA labels say about taking them together
Methadone and vandetanib
Vandetanib's FDA label of April 23, 2026 names methadone in its warnings and precautions section; the methadone labels PlainMeds reads (4) do not name vandetanib. The vandetanib label: “Avoid administration of CAPRELSA with anti-arrhythmic drugs and other drugs that may prolong the QT interval.”
Check it at the source: the methadone FDA label on DailyMed (effective December 8, 2025, Epic Pharma, LLC); the vandetanib FDA label on DailyMed (effective April 23, 2026, Genzyme Corporation).
What does the methadone label say about vandetanib?
Methadone's label (effective December 8, 2025) and its 3 other brand-application labels do not name vandetanib in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Methadone Hydrochloride), Epic Pharma, LLC, effective December 8, 2025 (SPL set 6da7501b-b881-4bc7-891a-74214a00a3ac), via openFDA; the full label on DailyMed
What does the vandetanib label say about methadone?
Vandetanib label, warnings and precautionsAvoid administration of CAPRELSA with anti-arrhythmic drugs (including but not limited to amiodarone, disopyramide, procainamide, sotalol, dofetilide) and other drugs that may prolong the QT interval (including but not limited to chloroquine, clarithromycin, dolasetron, granisetron, haloperidol, methadone, moxifloxacin, and pimozide) [see Drug Interactions (7.4) and Clinical Pharmacology (12.2) ].
Source: FDA drug label (CAPRELSA), Genzyme Corporation, effective April 23, 2026 (SPL set e5721cb8-4185-47b9-bbb3-1c587e558a03), 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
| Methadone | Vandetanib | |
|---|---|---|
| Labeled for | Pain, Opioid use disorder | n/a |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.177 per tablet 10 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