What is this medicine?

DIPHENHYDRAMINE (dye fen HYE dra meen) is an antihistamine. It is used to treat the symptoms of an allergic reaction. It is also used to treat Parkinson's disease. This medicine is also used to prevent and to treat motion sickness and as a nighttime sleep aid.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:

• asthma or lung disease
• glaucoma
• high blood pressure or heart disease
• liver disease
• pain or difficulty passing urine
• prostate trouble
• ulcers or other stomach problems
• an unusual or allergic reaction to diphenhydramine, other medicines foods, dyes, or preservatives such as sulfites
• pregnant or trying to get pregnant
• breast-feeding

How should I use this medicine?

Take this medicine by mouth with a full glass of water. Follow the directions on the prescription label. Take your doses at regular intervals. Do not take your medicine more often than directed. To prevent motion sickness start taking this medicine 30 to 60 minutes before you leave.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

Patients over 65 years old may have a stronger reaction and need a smaller dose.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following medications:

• MAOIs like Carbex, Eldepryl, Marplan, Nardil, and Parnate

This medicine may also interact with the following medications:

• alcohol
• barbiturates, like phenobarbital
• medicines for bladder spasm like oxybutynin, tolterodine
• medicines for blood pressure
• medicines for depression, anxiety, or psychotic disturbances
• medicines for movement abnormalities or Parkinson's disease
• medicines for sleep
• other medicines for cold, cough or allergy
• some medicines for the stomach like chlordiazepoxide, dicyclomine

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.