Two medicines, side by side
Dexamethasone vs diphenhydramine
Dexamethasone and diphenhydramine are both labeled for pain and allergies. Drugs@FDA records approvals of dexamethasone since 1958 and of diphenhydramine since 1946. Pharmacies paid $0.193 per dexamethasone 4 mg tablet and $0.898 per mL (Diphenhydramine 50 mg/mL vial) (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. In FDA's classes, dexamethasone is a corticosteroid and diphenhydramine a histamine-1 receptor antagonist.
Check it at the source: the dexamethasone FDA label on DailyMed (effective June 6, 2025); the diphenhydramine FDA label on DailyMed (effective November 18, 2025).
Highlights of the dexamethasone record
Dexamethasone (Decadron) · label of June 6, 2025
Used for
From the label: indicationsAllergic States Control of severe or incapacitating allergic conditions intractable to adequate trials of conventional treatment in asthma, atopic dermatitis, contact dermatitis, drug hypersensitivity reactions, perennial or seasonal allergic rhinitis, and serum sickness. […]
On the market
- Earliest approval on file
- October 30, 1958
- Generic labelers
- 60 labelers
- Pharmacy cost
- $0.193 per tablet
Supply and safety
- Shortage
- In shortage
- Recalls
- 8
Highlights of the diphenhydramine record
Diphenhydramine (Benadryl) · label of November 18, 2025
Used for
From the label: indicationsDiphenhydramine hydrochloride injection, USP is effective in adults and pediatric patients, other than premature infants and neonates, for the following conditions when the oral form is impractical. […]
On the market
- Earliest approval on file
- March 4, 1946
- Generic labelers
- 20 labelers
- Pharmacy cost
- $0.898 per mL
Supply and safety
- Shortage
- No current entry
- Recalls
- 8
Source: FDA drug labels via openFDA (Dexamethasone label of June 6, 2025, Diphenhydramine label of November 18, 2025); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do dexamethasone and diphenhydramine differ on the record?
In FDA's classes, dexamethasone is a corticosteroid and diphenhydramine a histamine-1 receptor antagonist.
Generics: dexamethasone since 1971; diphenhydramine since 1972 (Drugs@FDA).
| Dexamethasone | Diphenhydramine | |
|---|---|---|
| Labeled for | Asthma, Eczema (atopic dermatitis), Leukemia, lymphoma and myeloma, Herpes and shingles, Crohn's disease and ulcerative colitis, Multiple sclerosis, Osteoarthritis, Rheumatoid arthritis, Psoriasis, Allergies, Anemia, Pain | Cough and cold, Allergies, Pain |
| Pharmacologic class | Corticosteroid | Histamine-1 Receptor Antagonist |
| How it works (label) | n/a | n/a |
| Half-life (label) | n/a | n/a |
| Earliest approval on file (Drugs@FDA) | October 30, 1958 | March 4, 1946 |
| First generic approved | October 20, 1971 | May 9, 1972 |
| Generic labelers (NDC) | 60 labelers | 20 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.193 per tablet (Dexamethasone 4 mg tablet) | $0.898 per mL (Diphenhydramine 50 mg/mL vial) |
| 12-month price change | -26% | +0.8% |
| Boxed warning | No | No |
| Shortage now | In shortage | No current entry |
| Recalls recorded | 8 | 8 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 304,163 | 164,832 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to dexamethasone
- every medicine labeled for the same conditions