What the FDA labels say about taking them together
Lidocaine/tetracaine and mexiletine
Lidocaine/tetracaine's FDA label of March 9, 2026 names mexiletine in its drug interactions section; the mexiletine label PlainMeds reads does not name lidocaine/tetracaine.
Check it at the source: the lidocaine/tetracaine FDA label on DailyMed (effective March 9, 2026, IPG PHARMACEUTICALS, INC.); the mexiletine FDA label on DailyMed (effective May 14, 2026, Macleods Pharmaceuticals Limited).
What does the lidocaine/tetracaine label say about mexiletine?
Lidocaine/tetracaine label, drug interactionsAntiarrhythmic Drugs PLIAGLIS should be used with caution in patients receiving Class I antiarrhythmic drugs (such as tocainide and mexiletine) since the systemic toxic effects are thought to be additive and potentially synergistic with lidocaine and tetracaine.
Source: FDA drug label (PLIAGLIS), NDA021717 (Crescita Therap), as published by IPG PHARMACEUTICALS, INC., effective March 9, 2026 (SPL set d854faa5-0af8-4684-b5cd-a0b8a91fb7cd), via openFDA; the full label on DailyMed
What does the mexiletine label say about lidocaine/tetracaine?
Mexiletine's label (effective May 14, 2026) does not name lidocaine/tetracaine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Mexiletine Hydrochloride), Macleods Pharmaceuticals Limited, effective May 14, 2026 (SPL set a61a07f6-0b48-4dcd-ad42-5d90f6e69ab1), 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
| Lidocaine/tetracaine | Mexiletine | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.222 per capsule 150 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