Itching / Allergies

Dosages for Diphenhydramine (Benadryl) for different weights

Medicine Name: Diphenhydramine (Benadryl) May Give Every 20/24 lbs. 25-37 lbs. 38-49 lbs. 50-99 lbs. 100+ lbs.
Liquid 12.5 mg/ 1 teaspoon (tsp) 6-8 hours 3/4 tsp. 1 tsp. 1-1/2 tsp. 2 tsp. -
Liquid 12.5 mg/ 5 milliliters (mL) 6-8 hours 4 mL 5 mL 7.5 mL 10 mL -
Chewable 12.5 mg 6-8 hours - 1 tab. 1-1/2 tab. 2 tab. 4 tab.
Tablets 25 mg 6-8 hours - 1/2 tab. 1/2 tab. 1 tab. 2 tab.
Capsules 25 mg 6-8 hours - - - 1 cap. 2 cap.

When to Use. 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 causes most babies to be sleepy). For colds, not advised at any age. (Reason: no proven benefits). They should be not be given if under 4 years old. If under 6 years, don't give products with more than one ingredient in them. (Reason: FDA recommendations 10/2008).
  • DOSE. Find the child's weight in the top row of the dose table. Look below the correct weight for the dose based on the product you have.
  • MEASURE the DOSE. Syringes and droppers are more accurate than teaspoons. If possible, use the syringe or dropper that comes with the medicine. If not, you can get a med syringe at drug stores. If you use a teaspoon, it should be a measuring spoon. (Reason: regular spoons are not reliable.) Keep in mind 1 level teaspoon equals 5 mL and that ½ teaspoon equals 2.5 mL. 
  • ADULT DOSE. 50 mg
  • HOW OFTEN. Repeat every 6 hours as needed.
  • CHILDREN’S BENADRYL FASTMELTS. Each fastmelt tablet equals 12.5 mg. They are dosed the same as chewable tablets.

Customized from Itching Allergies v0.1 7/8/2025

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Measles update

February 12, 2026
There have been cases of measles in NC, with exposures in Chapel Hill, Durham, and Wake County. We can give the MMR dose early to families who want it. This applies to infants 6-12 months who have not gotten a dose yet or kids under 4-5 years who have not gotten their second MMR dose. At this time, the NC DHHS and health departments are not recommending this unless traveling or living in an area with sustained transmission. Two doses of the MMR vaccine are highly effective (97%) at preventing measles infections. At CHCAC, children receive their first dose at 12 months of age and a second dose at 4 years of age, ensuring they are fully protected as soon as possible, in accordance with the most up-to-date AAP recommendations. Some infants aged 6 months to 11 months who travel internationally or in high-prevalence areas may need a dose to protect them; however, they still require the 1-year and 4-year-old doses as well. If you are ever concerned about a possible exposure to measles, please CALL before entering our office. DO NOT ENTER the office. NC DHHS keeps a list of areas with measles exposures here . This is a highly contagious illness, and special precautions must be taken to prevent spread. The virus can be present in the air for 2 hours after an infected person is in the room, and 90% of susceptible patients can be infected. As always, if you have questions, we are here to help make sense of it all!