What is the appropriate dosing and timing of Diphenhydramine (Benadryl) for a 10-year-old patient with urticaria (hives)?

From the Guidelines

For a 10-year-old child with hives, the recommended dose of Benadryl (diphenhydramine) is 1 to 2 mg/kg per dose, with a maximum dose of 50 mg, as stated in the guidelines for the diagnosis and management of food allergy in the United States 1. The dose can be administered orally, with the option of using a liquid form for easier administration.

• The medication should be given at the first sign of hives and continued as needed until symptoms resolve.
• It is essential to be aware that Benadryl commonly causes drowsiness, so the child may feel sleepy after taking it.
• If the hives are severe, cover a large portion of the body, affect breathing, or are accompanied by facial swelling, seek immediate medical attention instead of relying solely on Benadryl.
• For persistent hives lasting more than a few days or recurring frequently, consult the child's doctor as this could indicate an underlying allergy requiring further evaluation. The use of antihistamines, such as Benadryl, is supported by recent guidelines, which emphasize their role in treating cutaneous signs and symptoms associated with anaphylaxis, although they should not be administered before or in place of epinephrine 1.
• Antihistamines act as inverse agonists at histamine receptors and are effective therapy for patients with urticaria, treating many of the cutaneous signs and symptoms associated with anaphylaxis, including pruritus, flushing, and urticaria.
• However, it is crucial to note that antihistamines are poorly effective in treating cardiovascular and respiratory symptoms, such as hypotension or bronchospasm, when used acutely as monotherapy.
• The timing of onset for antihistamines may be considered too slow for the treatment of anaphylaxis, and they lack the vasoconstrictive, bronchodilatory, ionotropic, and mast cell stabilization properties of epinephrine.

From the FDA Drug Label

Directions • take every 4 to 6 hours, or as directed by a physician• do not take more than 6 doses in 24 hours agedose Adults and children over 12 years of age10 mL (25 mg) to 20 mL (50 mg) Children 6 to under 12 years of age10 mL (25 mg) Children under 6 years of ageDo not use

For a 10-year-old with hives, the recommended dose is 10 mL (25 mg). The medication should be taken every 4 to 6 hours, with a maximum of 6 doses in 24 hours 2.

From the Research

Benadryl Dosing and Timing for a 10-Year-Old with Hives

• The provided studies do not directly address the dosing and timing of Benadryl for a 10-year-old with hives 3, 4, 5, 6, 7.
• However, it is known that antihistamines like Benadryl are commonly used to treat urticaria (hives) and anaphylaxis 4, 6, 7.
• The studies suggest that epinephrine is the first-line treatment for anaphylaxis, and antihistamines may be used as an adjunct therapy 4, 6.
• There is no specific guidance on the dosing and timing of Benadryl for a 10-year-old with hives in the provided studies.
• It is recommended to consult a healthcare professional for proper diagnosis and treatment of hives and anaphylaxis, as they can provide personalized guidance on medication dosing and timing 3, 7.

Treatment of Hives and Anaphylaxis

• Urticaria (hives) can be acute or chronic, and the treatment approach may vary depending on the underlying cause 3.
• Anaphylaxis is a life-threatening allergic reaction that requires immediate treatment with epinephrine 4, 6.
• Antihistamines and corticosteroids may be used in the treatment of anaphylaxis, but their role is not as well-established as epinephrine 5, 6.
• The provided studies highlight the importance of proper diagnosis and treatment of hives and anaphylaxis, and the need for healthcare professionals to be aware of the latest guidelines and recommendations 3, 4, 6, 7.