How should I take diphenhydramine?
Take diphenhydramine exactly as directed on the package or as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.
Take each dose with a full glass of water.
Diphenhydramine can be taken with or without food.
For motion sickness, a dose is usually taken 30 minutes before motion, then with meals and at bedtime for the duration of exposure.
As a sleep aid, diphenhydramine should be taken approximately 30 minutes before bedtime.
To ensure that you get a correct dose, measure the liquid forms of diphenhydramine with a special dose-measuring spoon or cup, not with a regular tablespoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.
Never take more of this medication than is prescribed for you. The maximum amount of diphenhydramine that you should take in any 24-hour period is 300 mg.
Store diphenhydramine at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication unless otherwise directed by your doctor.
What happens if I overdose?
Seek emergency medical attention if an overdose is suspected.
Symptoms of a diphenhydramine overdose include extreme sleepiness, confusion, weakness, ringing in the ears, blurred vision, large pupils, dry mouth, flushing, fever, shaking, insomnia, hallucinations, and possibly seizures.