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DIPHENHYDRAMINE (dye fen HYE dra meen) treats occasional insomnia. It helps you go to sleep. It belongs to a group of medications called antihistamines.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Unisom
They need to know if you have any of these conditions:
Take this medication 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 medication more often than directed.
Talk to your care team regarding the use of this medication in children. While this medication may be prescribed for children as young as 12 years old for selected conditions, precautions do apply.
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Patients over 65 years old may have a stronger reaction and may 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.
This does not apply; this medication is not for regular use. Do not take double or extra doses.
Do not take this medication with any of the following:
This medication may also interact with the following:
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.
Tell your care team if your symptoms do not start to get better or if they get worse. See your care team 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 care team if the problem does not go away or is severe.
This medication 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 medication 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 medication. Avoid alcoholic drinks.
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
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This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Keep out of the reach of children and pets. This medication can be abused. Keep your medication in a safe place.
Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Keep in the original blister package until time of use. Throw away any unused medication after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.