A child weighing 30 kg arrives at the clinic with diffuse itching as the result of an allergic reaction to an insect bite. Diphenhydramine (Benadryl) 25 mg 3 times a day is prescribed. The correct pediatric dose is 5 mg/kg/day. Which of the following best describes the prescribed drug dose?
A. It is the correct dose
B. The dose is too low
C. The dose is too high
D. The dose should be increased or decreased, depending on the symptoms
Correct Answer: B. The dose is too low
This child weighs 30 kg, and the pediatric dose of diphenhydramine is 5 mg/kg/day (5 X 30 = 150/day). Therefore, the correct dose is 150 mg/day. Divided into 3 doses per day, the child should receive 50 mg 3 times a day rather than 25 mg 3 times a day. Dosage should not be titrated based on symptoms without consulting a physician.
Option A: Diphenhydramine is used to relieve red, irritated, itchy, watery eyes; sneezing; and runny nose caused by hay fever, allergies, or the common cold. Diphenhydramine is also used to relieve coughs caused by minor throat or airway irritation.
Option C: Diphenhydramine comes as a tablet, a rapidly disintegrating (dissolving) tablet, a capsule, a liquid-filled capsule, a dissolving strip, powder, and a liquid to take by mouth. When diphenhydramine is used for the relief of allergies, cold, and cough symptoms, it is usually taken every 4 to 6 hours.
Option D: Before you give a diphenhydramine product to a child, check the package label to find out how much medication the child should receive. Give the dose that matches the child’s age on the chart. Ask the child’s doctor if you don’t know how much medication to give the child.