Antihistamines

Antihistamines: Combating Allergies and Histamine-Related Symptoms

Introduction:
Allergic reactions are a common phenomenon experienced by many people around the world. They can manifest themselves in the form of itching, redness, swelling, runny nose, cough and other unpleasant symptoms. The main substance responsible for the occurrence of these symptoms is histamine, a biologically active substance released in the body in response to allergens. However, thanks to the development of antihistamines, people can find relief from allergic symptoms.

What are antihistamines:
Antihistamines (also known as antihistamines) are pharmacological drugs designed to block the effects of histamine. Histamine is a key mediator of allergic reactions and causes smooth muscle contraction, vasodilation and increased capillary permeability. Antihistamines work by blocking histamine receptors, which helps prevent or reduce allergy symptoms.

How they work:
Antihistamines act on histamine receptors in the body. Histamine binds to certain receptors (H1 receptors) located on various cells such as capillaries, nasal mucosa and bronchial tubes. This causes narrowing of the airways, increased vascular permeability and other allergic symptoms. Antihistamines penetrate the blood and bind to histamine receptors, blocking their activity. This helps prevent or reduce the symptoms of an allergic reaction.

Different generations of antihistamines:
Antihistamines can be classified into several generations depending on their properties and side effects.

First generation of antihistamines:
First generation drugs such as diphenhydramine and chlorpheniramine were introduced to the market in the first half of the 20th century. They have sedative properties and may cause drowsiness, which limits their use in everyday life. First generation drugs also have a short effect and require frequent dosing.

Second generation antihistamines:
Second-generation drugs such as cetirizine, loratadine and fexofenadine have been developed to improve efficacy and reduce side effects. They have less ability to penetrate the blood barrier and cause drowsiness, so they can be taken during the day without a significant effect on psychomotor functions. Second-generation drugs have a longer action, which allows you to take them once or twice a day.

Third generation of antihistamines:
Recent research has led to the development of third-generation drugs such as desloratadine and levocetirizine. They are highly selective for histamine receptors and are even safer and more effective than previous generations. Third-generation drugs are characterized by a long-lasting effect, which allows them to be taken once a day.

Indications and use:
Antihistamines are widely used to treat various allergic reactions such as seasonal and perennial allergic rhinitis, urticaria, atopic dermatitis and allergic conjunctivitis. They help reduce the intensity of symptoms such as itching, runny nose, sneezing and skin rashes. Some antihistamines can also be used to prevent allergic reactions before exposure to known allergens.

Side effects:
Antihistamines are generally well tolerated by patients, but they may cause some side effects in some people. Some of the common side effects include dry mouth, headache, fatigue, and rarely, drowsiness. In rare cases, serious side effects may occur, so it is recommended that you consult your doctor before taking antihistamines.

Conclusion:
Antihistamines are an effective treatment for allergic reactions and associated symptoms. They block the action of histamine and help prevent or reduce allergy-related symptoms. The choice of a specific antihistamine may depend on the individual needs of the patient and the recommendations of the doctor.

Like other medications, antihistamines help manage allergy symptoms. These drugs block the activity of histamine, which causes inflammation, swelling, itching and other unpleasant sensations in humans. There are several categories of antihistamines, each of which works differently:

1. First generation antihistamine. The most famous representative of this group is diphenhydramine. They are usually more effective because they penetrate the bloodstream better and block histamine receptors on nerve tissue. However, their disadvantage is that they do not cope with the symptoms of the disease quickly (maximum 3