antihistaminiká

Antihistaminiká, also known as antihistamines, are a class of drugs that primarily work by blocking the action of histamine. Histamine is a natural chemical produced by the body's immune system that plays a role in allergic reactions. When the body encounters an allergen, such as pollen or dust mites, it releases histamine, which then binds to specific receptors on cells. This binding can cause symptoms like itching, sneezing, runny nose, watery eyes, and hives.

Antihistamines are used to treat a variety of conditions associated with histamine release, most commonly allergic conditions. These include hay fever (allergic rhinitis), hives (urticaria), insect bites, and certain types of food allergies. They can also be effective in reducing the symptoms of the common cold, although they do not cure the cold itself. Some antihistamines are also used to treat motion sickness and insomnia due to their sedative properties.

There are several types of antihistamines, broadly categorized into first-generation and second-generation. First-generation antihistamines, such as diphenhydramine, are known for their sedative effects as they can cross the blood-brain barrier easily. Second-generation antihistamines, like loratadine and cetirizine, are generally non-sedating or less sedating because they do not cross the blood-brain barrier as readily. Antihistamines are available in various forms, including tablets, capsules, syrups, nasal sprays, and eye drops. While generally safe, potential side effects can include drowsiness, dry mouth, dizziness, and blurred vision, particularly with first-generation medications.