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What is the dosage amount of children's Benadryl to give a 4 year old child who weighs 30 lbs?

Medically reviewed by Drugs.com. Last updated on April 8, 2024.

Official answer

by Drugs.com

Children’s Benadryl Allergy Liquid (diphenhydramine HCl 12.5 mg/5 mL) should not be used in children between the ages of 2 and 5 years unless directed by a doctor.

For additional information see Diphenhydramine Dosage or Benadryl Dosage Charts for Infants and Children.

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The Hat Man is a fictional figure that started appearing on certain internet sites in the early 2000s that has recently been referred to as the “Benadryl Hat Man” after reports of people hallucinating and sighting him after overconsumption or abuse of Benadryl. Most of these reports have appeared on Reddit or the image-based bulletin site 4chan. Continue reading

Benadryl is quickly absorbed after oral administration and it starts to work within 30 minutes with peak effects reached within one to two hours. The effects of Benadryl last from four to six hours. Benadryl in the injectable form has a rapid onset of action. You will know when Benadryl starts to work because your allergy symptoms, such as congestion, runny nose, itchy eyes, or a skin rash, will start to feel better. Continue reading

One of the most common side effects with Benadryl is drowsiness, but in some people it can have the opposite effect, known as paradoxical excitation. Instead of feeling sleepy,
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