Follow the directions on the label or as advised by your doctor. Diphenhydramine should only be used for a brief period of time, until your symptoms have subsided.

Take diphenhydramine 30 minutes before you will be in a setting that produces motion sickness (such as a long car journey, aeroplane or boat travel, amusement park rides, etc.) to prevent motion sickness. Continue taking diphenhydramine with meals and at bedtime for the remainder of the time you will be motion-sick.

As a sleep aid, take diphenhydramine within 30 minutes before bedtime.

You must chew the before you swallow it. chewable tablet

Measure carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon). liquid medicine

Remove an from the package only when you are ready to take the medicine. Place the tablet in your mouth and allow it to dissolve, without chewing. Swallow several times as the tablet dissolves. orally disintegrating tablet

Do not use diphenhydramine for longer than 2 weeks to treat sleep problems, or longer than 7 days to treat cold or allergy symptoms.

This medicine can affect the results of allergy skin tests. Tell any doctor who treats you that you are using diphenhydramine.

Taking too much diphenhydramine can lead to serious heart problems, seizures, coma, or death.

When providing diphenhydramine to a child, always follow the guidelines on the drug label. Antihistamine usage can result in death in extremely young children.Do not take the medication solely to put a child to sleep.