Antihistamine

Drug that blocks histamine or histamine agonists

Antihistamines are drugs that counteract the effects of histamine in the body, such as allergies and gastrointestinal conditions. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides relief from nasal congestion, sneezing, or hives caused by pollen, dust mites, or animal allergy with few side effects. Antihistamines are usually for short-term treatment.

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