Antihistamine medications are a class of drugs commonly used to relieve allergy symptoms and manage various allergic conditions. They work by blocking the effects of histamine, a chemical released by the body in response to allergens.
First-generation antihistamines have been in use for many years. They are effective but often cause drowsiness and may impair cognitive and motor skills.
Second-generation antihistamines are newer and have been developed to reduce drowsiness and other side effects.
Third-generation antihistamines are similar to second-generation antihistamines plus have a faster onset and longer duration.
Prescription antihistamines are used to treat severe allergies or chronic conditions.