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How many benadryls do you take: BENADRYL® Dosing Guide: Adult & Children’s Diphenhydramine Dosage

Diphenhydramine – Benadryl etc – Dosage Table | Health & Wellness Library | University Hospitals Rainbow Babies & Children’s Hospital | Cleveland, OH

Diphenhydramine (Benadryl, etc.) Dosage
Child’s weight20 – 24 lbs.25 – 37 lbs.38 – 49 lbs.50 – 99 lbs.Over 100 lbs.
Liquid 12.5 mg/5 milliliters (ml)457.510
Chewable 12.5 mg “>124
Tablets 25 mg½½12
Capsules 25 mg12


Treatment of allergic reactions, nasal allergies, hives and itching.

Table Notes:

  • AGE LIMITS: For allergies, don’t use under 1 year of age (Reason: it’s a sedative). For colds, not recommended at any age (Reason: no proven benefits) and should be avoided if under 4 years old. Avoid multi-ingredient products in children under 6 years of age (Reason: FDA recommendations 10/2008).
  • DOSAGE: Determine by finding child’s weight in the top row of the dosage table
  • MEASURING the DOSAGE: Syringes and droppers are more accurate than teaspoons. If possible, use the syringe or dropper that comes with the medication.  If not, medicine syringes are available at pharmacies. If you use a teaspoon, it should be a measuring spoon. Regular spoons are not reliable. Also, remember that 1 level teaspoon equals 5 ml and that ½ teaspoon equals 2.5 ml.
  • ADULT DOSAGE: 50 mg
  • FREQUENCY: Repeat every six hours as needed
  • CHILDREN’S BENADRYL FASTMELTS: Each fastmelt tablet contains the equivalent of 12.5 mg of Diphenhydramine HCL and dosed the same as chewable tablets.

Author and Senior Reviewer: Barton D. Schmitt, M.D.
Content Set: Pediatric HouseCalls Symptom Checker
Pediatric HouseCalls Symptom Checker

How Much Benadryl Can I Take Safely?

Written by
Juhi Modi

Medically reviewed by
HaVy Ngo-Hamilton, Pharm.D.
| May 25, 2022

Benadryl is a common over-the-counter medicine used to relieve symptoms of allergic rhinitis (hay fever) and the common cold, such as runny nose, sneezing, and watery/itchy eyes. It is also used to provide relief from irritated or itchy skin caused by insect bites, hives, eczema, sunburn, and other medical conditions like motion sickness and insomnia. All in all, it has a great variety of uses.

While it is an effective drug, the risk with exemplary over-the-counter medications like Benadryl is that you can easily continue taking it for symptomatic relief without noticing that you are going over the recommended dosage. Doing so can lead to severe side effects. 

This article will discuss the appropriate doses and the risks of taking too much Benadryl.

What is Benadryl?

Brand name Benadryl contains the active ingredient diphenhydramine. It is an over-the-counter antihistamine that helps relieve symptoms of seasonal allergies, the common cold, and itchy skin due to bug bites or allergic reactions. 

Benadryl is available in many different forms, including:

  • Oral (to be taken by mouth): tablets, chewable tablets, liquid-filled capsules,liqui-gels, and liquid solution
  • Topical (to be applied to the skin): creams, gels, and sprays

Some combination products contain diphenhydramine as the main ingredient along with other ingredients. For example, Benadryl Allergy Plus Congestion for Sinus Pressure & Nasal Congestion Relief contains diphenhydramine, an antihistamine, and phenylephrine, a nasal decongestant.

What is the correct Benadryl dosage?

The correct Benadryl dosage depends on several factors. Among those factors is the condition you’re treating, your age, and the form of Benadryl you’re using. Your physician will advise you to take the lowest effective dose of Benadryl for the shortest possible time as best practice recommends.

Regarding effective Benadryl dosing, commonly used and recommended doses of Benadryl are as follows:

For hay fever, allergies, and common cold symptoms

The recommended dose for adults and children 12 years and older is 25 mg to 50 mg every 4 to 6 hours. 

The recommended dose for children between the ages of 6-12 is 12.5 mg to 25 mg every 4 to 6 hours. 

Children under the age of 6 e should not take oral Benadryl without a doctor’s prescription. 

For itchy skin from insect bites, stings, hives, allergic reactions, or other causes

Adults and children from age 2+ can use the topical form of Benadryl and apply gel, cream, or spray to the affected area up to 4 times daily unless the area is widespread and the oral form is advised by a healthcare professional. Children under 2 years of age should use Benadryl topical products only if advised by a physician.

This is a general dosing guide. Some patients, for example, elderly patients, may need to take lower doses of this medication. If you have any specific questions about Benadryl dosages regarding your age and condition, you should consult your doctor or pharmacist. 

What is the maximum dosage of Benadryl?

The maximum dose of Benadryl for adults and children over 12 years of age is 300 mg per day. The maximum dose of Benadryl for children between the ages of  6 to 12 is 150 mg per day. Do not take more than 6 doses of oral Benadryl in 24 hours. 

Benadryl topical products (creams, gels, sprays) should not be applied to the skin more than 4 times a day.

It is important to check all your other antihistamines and ensure that your other medications don’t contain the same active ingredient, i.e., diphenhydramine. The maximum dose mentioned above is the dose you can safely take from all products and different forms combined.

What are Benadryl’s side effects?

The common side effects of Benadryl include sleepiness, dizziness, headache, dry mouth, dry eyes, and weakness. If these symptoms are severe or do not go away after a few days, talk to your doctor or pharmacist.

Benadryl can also cause more serious side effects, such as problems with cognition (thinking),  memory, fast heartbeat (tachycardia), and seizures. Contact your doctor if you experience these side effects and seek emergency medical care for serious side effects such as seizures. 

What are Benadryl risks and drug interactions?

Benadryl can cause drowsiness, which can impair your ability to drive, operate heavy machinery, or do anything that requires focus. Falling asleep at the wheel can result in accidents, so follow your doctor’s instructions and do not drive while taking Benadryl until you know how this medication affects you.

If you are taking other drugs, talk to a healthcare provider before taking Benadryl to avoid serious drug interactions. For example, taking Benadryl with benzodiazepines (Valium, Xanax, Klonopin) can increase the risk of confusion, drowsiness, and delirium. Mixing Benadryl and alcohol can lead to drowsiness and sedation, increasing the risk of accidents and injuries.

How many days in a row can you take Benadryl?

You should not use over-the-counter (OTC) Benadryl for longer than 7 days as treatment for cold and allergy symptoms. OTC Benadryl is intended for short-term use to provide temporary relief of allergy symptoms. If your symptoms do not improve after a week of Benadryl use, contact your doctor to obtain an accurate diagnosis and discuss alternative treatments.

What happens if you take too much Benadryl?

Scientists do not know a lot about the side effects of taking Benadryl long-term, but it has been linked to conditions such as:

  • Constipation
  • Weight gain
  • Blurred vision
  • Hallucinations 
  • Memory problems, confusion, dementia
  • Restless legs syndrome
  • Depression and anxiety
  • Tolerance and dependence

Can you overdose on Benadryl?

Yes, you can overdose on Benadryl. Signs and symptoms of a Benadryl overdose may include:

  • Confusion
  • Blurred vision
  • Dry mouth
  • Dizziness
  • Heart arrhythmia
  • Difficulty breathing
  • Irritability
  • Restlessness
  • Confusion
  • Hallucinations
  • Shock
  • Seizures
  • Coma
  • Death

If you or someone you know may have overdosed on Benadryl, call 911 or seek care at the nearest emergency room without delay.

Wrapping Up: Safe use of over the counter medications like Benadryl

It is not safe to take more than the recommended dosage of over-the-counter medicines like Benadryl. Taking too much Benadryl can cause serious problems, including hallucinations, abnormal heart rhythms, seizures, and even death. Always read the labels on OTC medications carefully and ensure that you take the recommended daily dosage. 


  1. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=702f9786-7ce9-43e4-921d-e1db09612127
  2. https://medlineplus.