SIDE EFFECTS: Diphenhydramine commonly can cause:
- disturbed coordination,
- drying and thickening of oral and other respiratory secretions, and
- urinary retention.
Diphenhydramine also may cause
- low blood pressure,
- increased heart rate,
- blurred vision,
- double vision,
- loss or appetite, or
Diphenhydramine should be used with caution (if at all) in persons with narrow-angle glaucoma, prostatic hypertrophy (enlarged prostate gland), hyperthyroidism, cardiovascular disease, high blood pressure (hypertension), and asthma.
GENERIC AVAILABLE: Yes
PRESCRIPTION: No. Yes (Injection)
- Capsules: 25 and 50 mg. Tablets: 12.5, 25 and 50 mg.
- Tablet (Chewable or dispersible)): 12.5 mg.
- Strips: 12.5 and 25 mg.
- Elixir, oral solution, liquid: 12.5 mg per teaspoon (5 mL).
- Strip: 25 mg. Injection: 50 mg per ml.
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