Diphenhydramine injection is used to treat allergic reactions, especially for people who are unable to take diphenhydramine by mouth. It is used also to treat motion sickness. Diphenhydramine injection is also used alone or along with other medications to control abnormal movements in people who have Parkinsonian syndrome (a disorder of the nervous system that causes difficulties with movement, muscle control, and balance). Diphenhydramine injection should not be used in newborn or premature infants. Diphenhydramine injection is in a class of medications called antihistamines. It works by blocking the action of histamine, a substance in the body that causes allergic symptoms.
Diphenhydramine injection comes as a solution (liquid) to be injected intramuscularly (into a muscle) or intravenously (into a vein). Your dosing schedule will depend on your condition and on how you respond to treatment.
You may receive diphenhydramine injection in a hospital or you may administer the medication at home. If you will be using diphenhydramine injection at home, your healthcare provider will show you how to use the medication. Be sure that you understand these directions, and ask your healthcare provider if you have any questions.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Before using diphenhydramine injection,
Unless your doctor tells you otherwise, continue your normal diet.
Diphenhydramine injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:
Diphenhydramine injection may cause other side effects. Call your doctor if you have any unusual problems while using this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( Web Site ) or by phone (1-800-332-1088).
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat and moisture (not in the bathroom).
Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website ( Web Site) for more information if you do not have access to a take-back program.
It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. Web Site
In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at Web Site. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
Symptoms of overdose may include the following:
Ask your pharmacist any questions you have about diphenhydramine injection.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
¶ This branded product is no longer on the market. Generic alternatives may be available.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: September 15, 2016.