| Allegra | Benadryl | |
|---|---|---|
| Generic | fexofenadine | diphenhydramine |
| Active ingredient | Fexofenadine HCl 180 mg (24 Hour) or 60 mg (12 Hour) | Diphenhydramine HCl 25 mg |
| Type | Oral antihistamine (pill) | Oral antihistamine (pill), older type |
| Label uses | runny nose, sneezing, itchy, watery eyes, itching of the nose or throat | runny nose, sneezing, itchy, watery eyes, itching of the nose or throat, common cold symptoms |
| Nasal congestion on label | No | No |
| Drowsiness | No drowsiness warning | Marked drowsiness |
| How often | Once a day (180 mg) or twice a day (60 mg) | Every 4 to 6 hours |
| Youngest age on label | 12 years | 6 years |
| Maximum | 1 x 180 mg or 2 x 60 mg tablets in 24 hours | 6 doses in 24 hours |
The main differences
Both are oral antihistamines and list the same core uses on the label: itching of the nose or throat, itchy, watery eyes, runny nose, sneezing.
On drowsiness: Allegra: The label has no drowsiness warning. Benadryl: The label warns "marked drowsiness may occur", and that excitability may occur, especially in children.
For children, Benadryl is labeled from age 6, while Allegra is labeled from age 12.
Dosing: Allegra is once a day (180 mg) or twice a day (60 mg); Benadryl is every 4 to 6 hours.
Which might suit you
- you need to stay alert during the day
- you can take it with water rather than juice and away from antacids
- you want a dose you can repeat every 4 to 6 hours and drowsiness is not a problem
- it is for a child aged 6 or older
This is based only on what the two labels say. Neither label claims to work better than the other. A pharmacist can help if you have other conditions or take other medicines.
Dose by age
Allegra
- Adults and children 12 and older (24 Hour): One 180 mg tablet with water once a day. Not more than 1 tablet in 24 hours.
- Adults and children 12 and older (12 Hour): One 60 mg tablet with water every 12 hours. Not more than 2 tablets in 24 hours.
- Children under 12: Do not use (these tablets).
- Adults 65 and older, or kidney disease: Ask a doctor.
Benadryl
- Adults and children 12 and over: 1 to 2 tablets every 4 to 6 hours. Not more than 6 doses in 24 hours.
- Children 6 to under 12: 1 tablet every 4 to 6 hours. Not more than 6 doses in 24 hours.
- Children under 6: Do not use.
Key warnings
Allegra
- Do not use if you have ever had an allergic reaction to this product or any of its ingredients.
- Ask a doctor before use if you have kidney disease.
- Do not take at the same time as aluminum or magnesium antacids.
- Do not take with fruit juices: take it with water.
Benadryl
- Do not use with any other product containing diphenhydramine, even one used on the skin.
- Do not use to make a child sleepy.
- Ask a doctor before use if you have glaucoma, a breathing problem such as emphysema or chronic bronchitis, or trouble urinating due to an enlarged prostate.
- Marked drowsiness may occur; excitability may occur, especially in children.
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Frequently asked questions
Is Allegra or Benadryl better?
Neither label claims to work better than the other. Which suits you depends on your symptoms, age, and whether drowsiness matters, as compared above. A pharmacist can help you choose.
Can you take Allegra and Benadryl together?
Both are antihistamines, and the labels don't cover combining them. Ask a pharmacist or doctor before combining allergy medicines.
Sources: Allegra Allergy Drug Facts label (Drugs.com, from the manufacturer's label); Benadryl Allergy Drug Facts label (OTCLabels, from DailyMed). Checked October 17, 2026. Not medical advice. How we check.