Diphenhydramine: Drowsy (sedating) Antihistamine - NHS

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Diphenhydramine - Brand names: Nytol Original, Boots Sleepeaze, Histergan

Find out how diphenhydramine treats symptoms of allergies and short-term insomnia, and how to take it.

• About diphenhydramine
• Who can and cannot take it
• How and when to take it
• Side effects
• Pregnancy, breastfeeding and fertility
• Taking it with other medicines and herbal supplements
• Common questions

Related conditions

• Atopic eczema
• Contact dermatitis
• Hay fever
• Hives
• Insect bites and stings
• Insomnia

Useful resources

• Allergy UK www.allergyuk.org
• Healthtalk: videos of real stories about sleep problems in later life healthtalk.org
• Itchy Sneezy Wheezy: website for parents www.itchysneezywheezy.co.uk