Generic name: Diphenhydramine Injection Solution [ dye-fen-HYE-dra-meen ]
Brand name: Benadryl
Drug classes: Anticholinergic antiemetics, Anticholinergic antiparkinson agents, Antihistamines, Miscellaneous anxiolytics, sedatives and hypnotics

Medically reviewed by Drugs.com. Last updated on May 20, 2023.

Uses of Diphenhydramine Injection Solution:

• It is used to ease allergy signs.
• It is used to help motion sickness.
• It is used to treat signs like Parkinson's disease caused by other health problems.

What do I need to tell my doctor BEFORE I take Diphenhydramine Injection Solution?

• If you have an allergy to diphenhydramine or any other part of diphenhydramine injection solution.
• If you are allergic to diphenhydramine injection solution; any part of diphenhydramine injection solution; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you are breast-feeding or plan to breast-feed.
• If the patient is a premature baby or a newborn. Do not give this form of diphenhydramine injection solution to a premature baby or a newborn.

This is not a list of all drugs or health problems that interact with diphenhydramine injection solution.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take diphenhydramine injection solution with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Diphenhydramine Injection Solution?

• Tell all of your health care providers that you take diphenhydramine injection solution. This includes your doctors, nurses, pharmacists, and dentists.
• Do not take more than what your doctor told you to take. Taking more than you are told may raise your chance of very bad side effects.
• Do not use diphenhydramine injection solution for longer than you were told by your doctor.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how diphenhydramine injection solution affects you.
• Do not use with other products that have diphenhydramine.
• Avoid drinking alcohol while taking diphenhydramine injection solution.
• Talk with your doctor before you use other drugs and natural products that slow your actions.
• Different brands of diphenhydramine injection solution may be for use in different ages of children. Talk with the doctor before giving diphenhydramine injection solution to a child.
• Do not use to make a child sleepy. Talk with the doctor.
• If you are 60 or older, use diphenhydramine injection solution with care. You could have more side effects.
• Use with care in children. Talk with the doctor.
• Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using diphenhydramine injection solution while you are pregnant.

How is this medicine (Diphenhydramine Injection Solution) best taken?

Use diphenhydramine injection solution as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• It is given as a shot into a muscle or vein.
• This medicine may cause tissue damage if it is given into the skin or into the fatty part under the skin. Talk with the doctor.

What do I do if I miss a dose?

• Call your doctor to find out what to do.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Very bad dizziness or passing out.
• Change in balance.
• Feeling less alert.

What are some other side effects of Diphenhydramine Injection Solution?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Feeling sleepy.
• Dizziness.
• Thickening of mucus in nose or throat.
• Feeling nervous and excitable.
• Upset stomach or throwing up.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Diphenhydramine Injection Solution?

• If you need to store diphenhydramine injection solution at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer Information Use and Disclaimer

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else's drugs.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about diphenhydramine injection solution, please talk with your doctor, nurse, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Frequently asked questions

• What is the max dose of diphenhydramine for adults?
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View more FAQ

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer