Antihistamines are mainly used to help control symptoms of health conditions associated with allergic reactions.
Antihistamines can’t cure these types of conditions, as they don’t affect the underlying cause, but they can often provide considerable symptom relief.
Conditions that can benefit from the use of antihistamines include:
- hay fever
- allergic rhinitis – inflammation of the nasal passages
- atopic eczema – a common allergic skin condition
- urticaria – also known as nettle rash or hives
- allergic conjunctivitis – inflammation of the eyes
- allergic reactions that are caused by insect bites or stings
- mild or moderate allergic reactions that are caused by food allergies – more severe allergic reactions (anaphylaxis) usually require treatment with adrenaline (a chemical that can reverse many of the processes associated with an allergic reaction)
Other uses
As well as being used to treat allergic conditions, antihistamines also have a number of other uses, including treating stomach ulcers (sores that develop on the lining of the stomach), insomnia (problems falling asleep) and motion sickness.
Stomach ulcers
Some types of antihistamine can be used to treat stomach ulcers by reducing the acid level in the stomach and digestive system. This is because histamine can stimulate the production of stomach acid.
Read more about treating stomach ulcers.
Insomnia
First-generation antihistamines may be of some benefit in the short-term treatment of insomnia, particularly if the symptoms of sleeplessness are caused by an underlying allergic condition, such as an allergic skin condition.
The long-term use of antihistamines to treat insomnia is not recommended because there are more effective treatments. In addition, there’s a risk that you could become addicted to the sedating effects of first-generation antihistamines.
Read more about treating insomnia.
Motion sickness
Antihistamines are sometimes also used to control the symptoms of nausea and vomiting associated with motion sickness.
Read more about treating motion sickness.