What the FDA labels say about taking them together
Ephedrine and histamine
Histamine's FDA label of November 3, 2025 names ephedrine in its drug interactions (prescription label) section; the ephedrine labels PlainMeds reads (4) do not name histamine. The histamine label: “Beta 2 Agonists: Oral terbutaline and parenteral ephedrine, in general, have been shown to decrease allergen induced wheal.”
Check it at the source: the ephedrine FDA label on DailyMed (effective September 16, 2024, Nexus Pharmaceuticals, LLC); the histamine FDA label on DailyMed (effective November 3, 2025).
What does the ephedrine label say about histamine?
Ephedrine's label (effective September 16, 2024) and its 3 other brand-application labels do not name histamine in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Emerphed PFS), Nexus Pharmaceuticals, LLC, effective September 16, 2024 (SPL set 14601778-93ac-43ec-b66b-5a942317133f), via openFDA; the full label on DailyMed
What does the histamine label say about ephedrine?
Histamine label, drug interactions (prescription label)Beta 2 Agonists: Oral terbutaline and parenteral ephedrine, in general, have been shown to decrease allergen induced wheal.
Source: FDA drug label (Histaminum hydrochloricum), Boiron, effective November 3, 2025 (SPL set 85b905d4-5fa3-7125-e053-2a91aa0a54f4), 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
| Ephedrine | Histamine | |
|---|---|---|
| Labeled for | Asthma | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | 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