home > drugs a-z list > benadryl (diphenhydramine) drug center > benadryl (diphenhydramine) drug - patient avoid while taking

In this Article

• What is diphenhydramine (Benadryl)?
• What are the possible side effects of diphenhydramine?
• What is the most important information I should know about diphenhydramine?
• What should I discuss with my healthcare provider before taking diphenhydramine?
• How should I take diphenhydramine?
• What happens if I miss a dose?
• What happens if I overdose?
• What should I avoid while taking diphenhydramine?
• What other drugs will affect diphenhydramine?
• Where can I get more information?

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication unless otherwise directed by your doctor.

What happens if I overdose?

Seek emergency medical attention if an overdose is suspected.

Symptoms of a diphenhydramine overdose include extreme sleepiness, confusion, weakness, ringing in the ears, blurred vision, large pupils, dry mouth, flushing, fever, shaking, insomnia, hallucinations, and possibly seizures.

What should I avoid while taking diphenhydramine?

Use caution when driving, operating machinery, or performing other hazardous activities. Diphenhydramine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking diphenhydramine.

What other drugs will affect diphenhydramine?

Do not take diphenhydramine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A very dangerous drug interaction could occur, leading to serious side effects.

Talk to your pharmacist before taking other over-the-counter cough, cold, allergy, or insomnia medications. These products may contain medicines similar to diphenhydramine, which could lead to an antihistamine overdose.

Before taking this medication, tell your doctor if you are taking any of the following medicines:

• anxiety or sleep medicines such as alprazolam (Xanax), diazepam (Valium), chlordiazepoxide (Librium), temazepam (Restoril), or triazolam (Halcion);
• medications for depression such as amitriptyline (Elavil), doxepin (Sinequan), nortriptyline (Pamelor), fluoxetine (Prozac), sertraline (Zoloft), or paroxetine (Paxil); or
• any other medications that make you feel drowsy, sleepy, or relaxed.

Drugs other than those listed here may also interact with diphenhydramine. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

Where can I get more information?

Your pharmacist can provide more information about diphenhydramine.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2010 Cerner Multum, Inc. Version: 5.01. Revision date: 04/02/2009.

Your use of the content provided in this service indicates that you have read,understood and agree to the End-User License Agreement,which can be accessed by clicking on this link.