Categories: Health

Benadryl Overdose: Signs & How to Take It Safely

Benadryl is the brand name of the active drug diphenhydramine. It belongs to the class of drugs called antihistamines. It is commonly used to treat symptoms of allergies, common cold, and hay fever.

Benadryl is an effective medicine and is easily available over-the-counter (OTC). Taking too much Benadryl, however, can lead to an overdose. When severe, a Benadryl overdose may cause hallucinations, seizures, coma, and even death. It should only be used as prescribed or as directed on the drug label.

When to Seek Help

In case of a Benadryl overdose, call the poison control helpline at 1-800-222-1222. You can also seek information online at poisonhelp.org/help.

You can reach your local poison control center by calling the Poison Control Center helpline (1-800-222-1222) in the United States.

If the user has collapsed, has seizures, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Getty Images / Smith Collection/Gado / Contributor


Symptoms of an Overdose

Symptoms of a Benadryl overdose may include:

  • Rapid heartbeat
  • Dry mouth
  • Enlarged pupils
  • Drowsiness
  • Tinnitus (ringing in the ears)
  • Nervousness
  • Nausea and vomiting
  • Low blood pressure
  • Tremor
  • Unsteadiness
  • Dry, red skin

At higher doses, an overdose can cause more severe symptoms such as:

  • Agitation
  • Confusion
  • Delirium (change in attention and awareness)
  • Inability to urinate
  • Vision problems
  • Hallucinations (seeing or hearing things that aren’t there)
  • Seizures

Complications

The U.S. Food and Drug Administration (FDA) warns that taking higher than recommended doses of Benadryl can cause life-threatening complications. It can cross the blood-brain barrier and cause central nervous system effects.

An overdose can lead to serious complications such as:

Treatment

Treatment is generally supportive and targets symptom control. Monitoring of vital signs may be required.

The healthcare provider may provide standard diagnostic tests such as:

There is currently no antidote that specifically works to reverse the effects of diphenhydramine toxicity. The major therapeutic goal is to control and reverse the symptoms of overdose in an individual.

Depending on the severity of symptoms, the management of a Benadryl overdose may include:

  • Constant cardiac monitoring
  • IV fluids for tachycardia (increased heart rate)
  • Medications to control specific symptoms, such as benzodiazepines for agitation and seizures, sodium bicarbonate to control abnormal heart rhythm, and physostigmine for altered mental status
  • Cooling measures for hyperthermia (increased body temperature)
  • Urinary catheter for fluid retention
  • Activated charcoal
  • Intravenous lipid emulsion in case of a cardiac arrest
  • Breathing and cardiac support (such as a ventilator)

How to Take It Safely

Benadryl is available in different formulations, including:

  • Benadryl film-coated tablets (25 milligrams [mg] of diphenhydramine)
  • Benadryl allergy extra strength film-coated tablets (50 mg of diphenhydramine)
  • Children’s Benadryl allergy solution (12.5 mg of diphenhydramine in every 5 milliliters [mL])
Benadryl Dosage and Frequency
Age Benadryl Dose Frequency
Adults and children 12 years and older 1 to 2 tablets Every 4 to 6 hours
Children 6 to under 12 years 1 tablet or 5 mL to 10 mL (Benadryl children solution) Every 4 to 6 hours
Children under 6 years Do not use unless directed by a healthcare provider As directed
Children under 2 years Do not use x

Always read the drug facts label on all OTC medicines or generic formulations to determine if they contain diphenhydramine, dosage, and how often they should be taken. Do not take more than the dose recommended on the label.

Benadryl Overdose in Children

Children’s Benadryl Allergy solution is approved for use in children above 6 years of age. It contains 12.5 mg of diphenhydramine.

Do not use this medication:

  • In children younger than 6 years without direction from a healthcare provider
  • To make a child sleepy
  • With any other product containing diphenhydramine, not even on the skin

An overdose of antihistamines, including Benadryl, may cause symptoms in children, such as:

  • Fast heart rate
  • Hallucinations
  • Drowsiness
  • Agitation
  • Convulsions
  • Dilated pupils
  • Dry mouth
  • Flushing
  • Gastrointestinal symptoms

Safe Medication Storage

According to a review of roughly 2,000 causes of Benadryl overdose occurring in young children, most (80%) involved accidental unsupervised ingestions.

Some safety tips for storing medication:

  • Keep medications stored up high and out of reach.
  • Use medication containers with safety caps. These are child-resistant and are more difficult for a young child to open.
  • Use safety latches or locks on medicine cabinets.
  • Never leave your medication open and unattended while it is within a child’s reach.

Be Aware of Combination Products

Many OTC and prescription medicines contain diphenhydramine alone or in combination with other drugs, such as pain relievers, fever reducers, and decongestants.

When using Benadryl, carefully read the label before taking any other OTC medicine. Tell your healthcare provider about all medicines you are taking to avoid diphenhydramine overdose.

Some commonly available diphenhydramine-containing products include:

  • Aler-Dryl
  • Diphenhist
  • Nytol
  • PediaCare Children’s Allergy
  • Siladryl
  • syllables
  • Sominex
  • Unisome

Some other combination products examples include:

  • Advil PM (diphenhydramine, ibuprofen)
  • Alahist LQ (diphenhydramine, phenylephrine)
  • Aldex CT (diphenhydramine, phenylephrine)
  • Aleve PM (diphenhydramine, naproxen)
  • Midol PM (acetaminophen, diphenhydramine)
  • Motrin PM (diphenhydramine, ibuprofen)
  • PediaCare Children’s Allergy and Cold (diphenhydramine, phenylephrine)
  • Robitussin Night Time Cough and Cold (diphenhydramine, phenylephrine)
  • Sudafed PE Day/Night Cold (acetaminophen, dextromethorphan, diphenhydramine, guaifenesin, phenylephrine)
  • Sudafed PE Day/Night Congestion (diphenhydramine, phenylephrine)

What Is the “Benadryl Challenge” and Why Is It Dangerous?

In 2020, news reports circulated of teenagers ending up in emergency rooms or dying after participating in the “Benadryl Challenge.” The viral TikTok challenge involves taking excessive amounts of Benadryl to get high, bring on hallucinations, and post videos online.

The FDA is aware of this challenge and warns against it. High intake of Benadryl can lead to serious heart problems, seizures, coma, or even death.

Summary

Benadryl is a commonly used antihistamine to treat the symptoms of seasonal allergies, hay fever, and the common cold. It relieves symptoms like sneezing, a runny nose, sore throat, and watery eyes.

Benadryl is generally safe, but taking more than the recommended dose can lead to an increased risk of side effects or overdose. If severe, an overdose can bring on more serious complications, such as seizures, coma, and even death.

If you or someone around you has taken more than the recommended amount of Benadryl, contact a medical provider or the Poison Control Center helpline.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Patel J, Edwards J. Treating diphenhydramine overdose: a literature review of currently available treatment methods. Toxics. 2024;12(6):376. doi:10.3390/toxics12060376

  2. Medline Plus. Diphenhydramine.

  3. Food and Drug Administration. Benadryl (diphenhydramine): Drug Safety Communication – serious problems with high doses of the allergy medicine.

  4. Medline Plus. Diphenhydramine overdose.

  5. Nishino T, Wakai S, Aoki H, Inokuchi S. Cardiac arrest caused by diphenhydramine overdose. Acute Med Surg. 2018;5(4):380-383. doi:10.1002/ams2.351

  6. DailyMed. Label: Benadryl- diphenhydramine hydrochloride tablet, film coated.

  7. DailyMed. Label: Benadryl allergy extra strength- diphenhydramine hydrochloride tablet, film coated.

  8. DailyMed. Label: Children Benadryl allergy- diphenhydramine hydrochloride solution.

  9. Palmer RB, Reynolds KM, Banner W, et al. Adverse events associated with diphenhydramine in children, 2008-2015. Clin Toxicol (Phila). 2020;58(2):99-106. doi:10.1080/15563650.2019.1609683

  10. Food and Drug Administration. FDA warns about serious problems with high doses of the allergy medicine diphenhydramine (Benadryl).

By Ayesha Gulzar, PharmD

Ayesha Gulzar is a clinical pharmacist interested in medical research, pharmacy practice, and medication therapy management. Dr. Gulzar has been working in medical communications, writing medical and clinical research for patients and health professionals in the United Kingdom.

Fitness Fusion HQ

View Comments

  • Its like you read my mind You appear to know a lot about this like you wrote the book in it or something I think that you could do with some pics to drive the message home a little bit but instead of that this is fantastic blog An excellent read I will certainly be back

  • Magnificent beat I would like to apprentice while you amend your site how can i subscribe for a blog web site The account helped me a acceptable deal I had been a little bit acquainted of this your broadcast offered bright clear idea

Recent Posts

The Number of Women Playing Wheelchair Rugby at the Paralympics Has Doubled Since Tokyo

On the first day of the 2024 Paralympic Games in Paris, Sarah Adam etched her…

1 hour ago

Why are we seeing more pandemics? Our impact on the planet has a lot to do with it

Pandemics – the global spread of infectious diseases – seem to be making a comeback.…

3 hours ago

Is It time to Add Cancer-Specific Warning Labels to Alcohol?

Key Takeaways Alcohol consumption is linked to six types of cancer, including breast and liver…

13 hours ago

The 8 Best Brain Supplements For Any Age, According to Registered Dietitians

  Everyone from students looking to improve concentration to working professionals trying to improve focus…

14 hours ago

The Best Sports Bras for High-Impact Workouts, According to Runners

And here’s one more feature that helps ensure consistent coverage: The bra’s padding is removable,…

15 hours ago

How to Create More Intimacy in Your Relationship

Intimacy, the feeling of closeness and emotional connection with another person, is the cornerstone of…

15 hours ago

This website uses cookies.