How and when to take or use diphenhydramine

The usual dose of diphenhydramine depends on the type of medicine you're taking, and why.

If you're aged over 65, start with the lower dose, as you may be more likely to get side effects.

Dosage for short-term insomnia

Diphenhydramine comes as 25mg and 50mg tablets for insomnia. The usual dose is 50mg, 20 minutes before you go to bed.

Dosage for cough and cold symptoms

Diphenhydramine comes mixed with other medicines to treat the symptoms of coughs and colds. It comes as tablets and as a liquid that you swallow.

The usual dose depends on the type of medicine you're taking. Check the instructions on the packaging carefully or ask your doctor or pharmacist if you're unsure.

Dosage for hay fever and allergies

Diphenhydramine comes as 25mg and 50mg tablets for hay fever and other allergies. The usual dose is 25mg or 50mg, taken 3 or 4 times a day. Try to space your doses evenly throughout the day.

Dosage for insect bites and stings or eczema

Diphenhydramine comes as a cream for insect bites and stings or eczema, which you use once or twice a day. You'll only need a small amount, enough for a thin layer.

How to take or use it

You can take diphenhydramine tablets and liquid with or without food.

How to take diphenhydramine tablets

Always take your diphenhydramine tablets with a drink of water. Swallow them whole. Do not chew them.

How to take diphenhydramine liquid

Liquid medicines containing diphenhydramine come with a plastic syringe or spoon to help you measure the right dose. If you do not have a syringe or spoon, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount.

How to use diphenhydramine cream

Put a small amount of diphenhydramine cream onto the affected area and smooth it in gently.

Do not use it on large areas of skin. Keep the cream away from your eyes, mouth and nose.

Wash your hands afterwards, unless you're treating your hands.