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Diphenhydramine Hydrochloride Oral disintegrating tablet [Insomnia]

This medicine is used to treat occasional sleeplessness

Generic Name: Unisom

What is this medicine?

DIPHENHYDRAMINE (dye fen HYE dra meen) is an antihistamine. This medicine is used to treat occasional sleeplessness.

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

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

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

How should I use this medicine?

Take this medicine by mouth. Follow the directions on the label. Leave the tablet in the sealed blister pack until you are ready to take it. With dry hands, open the blister and gently remove the tablet. If the tablet breaks or crumbles, throw it away and take a new tablet out of the blister pack. Place the tablet in the mouth and allow it to dissolve, and then swallow. While you may take these tablets with water, it is not necessary to do so. Do not take your medicine more often than directed.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children as young as 12 years old for selected conditions, precautions do apply.

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

Overdosage: If you think you've taken too much of this medicine contact a poison control center or emergency room at once.

What if I miss a dose?

This does not apply; this medicine is not for regular use. 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
-other medicines that contain diphenhydramine
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

What should I watch for while using this medicine?

Tell your doctor or health care professional if your symptoms do not start to get better or if they get worse. See your doctor if you have trouble sleeping every night for more than 2 weeks.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.

This medicine may cause dry eyes and blurred vision. If you wear contact lenses you may feel some discomfort. Lubricating drops may help. See your eye doctor if the problem does not go away or is severe.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.


Last Updated: August 08, 2011
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