What the FDA labels say about taking them together
Dimenhydrinate and diphenhydramine
Dimenhydrinate's FDA label of August 17, 2026 names diphenhydramine in its contraindications (prescription label) section; the diphenhydramine label PlainMeds reads does not name dimenhydrinate.
Check it at the source: the dimenhydrinate FDA label on DailyMed (effective August 17, 2026); the diphenhydramine FDA label on DailyMed (effective November 18, 2025, Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.).
What does the dimenhydrinate label say about diphenhydramine?
Dimenhydrinate label, contraindications (prescription label)CONTRAINDICATIONS Neonates and patients with a history of hypersensitivity to dimenhydrinate or its components (diphenhydramine or 8-chlorotheophylline) should not be treated with dimenhydrinate.
Source: FDA drug label (Motion Sickness), Strategic Sourcing Services LLC, effective August 17, 2026 (SPL set be8f91d4-6e4f-4d47-93e9-7fb91160b7df), via openFDA; the full label on DailyMed
What does the diphenhydramine label say about dimenhydrinate?
Diphenhydramine's label (effective November 18, 2025) does not name dimenhydrinate in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Diphenhydramine Hydrochloride), Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc., effective November 18, 2025 (SPL set 6178d3a1-0741-49a4-be81-c4f7d29f8b2a), 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
| Dimenhydrinate | Diphenhydramine | |
|---|---|---|
| Labeled for | Nausea and vomiting | Cough and cold, Allergies, Pain |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.0575 per tablet 50 mg tablet | $0.898 per mL 50 mg/mL vial |
| 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