How does the skin often feel itchy when the weather is hot?

Skin itching is nonspecific and can be a symptom of many diseases. Your father's symptoms may be itchy skin, with many causes, such as dry skin, contact with or eating allergic substances, systemic diseases (such as diabetes, hypertension, poor liver and kidney function, etc. ), so pay attention to observe allergic factors and check some diseases in life. Antihistamines can be used in the treatment, and second-generation antihistamines such as ebastine or mizolastine can be selected. It is recommended to take medicine under the guidance of a doctor. Some external emollients and antiallergic ointment can also be added. Use less alkaline soap when taking a bath.

Itchy skin

Itching is generally thought to be caused by skin diseases. The most common is senile itching in winter. The reason is that due to hypogonadism and endocrine function, sebaceous glands and sweat glands atrophy in the elderly, the skin is too dry, and the nerve endings distributed on the shriveled skin are aging and degenerating, sending strange stimulation signals to the center, causing skin itching, especially in severe winter.

Other skin itching, especially obvious, persistent or recurrent itching, but without any rash at the same time or at the same time, are mostly signals of various diseases. It is necessary to go to the hospital in time and treat it early to avoid serious illness.

Digestive system diseases: Common hepatobiliary diseases, including obstructive jaundice and hemolytic jaundice, cause systemic skin itching due to the increase of bile salt concentration in serum and skin, which stimulates nerve endings. Endocrine disorders in pregnant women can lead to "pregnancy itching", because estrogen and progesterone increase during pregnancy and disappear automatically after delivery.

Endocrine system diseases: About 19% of patients with hyperthyroidism and hypothyroidism have itchy skin, but there are differences between them. Itching of hyperthyroidism appears earlier, and it is aggravated by moist skin of hyperthyroidism in summer. The itch of "hypothyroidism" appears later, develops slowly, the skin is drier and rougher, and it is easier to induce itching in winter. Diabetes patients are more susceptible to bacterial and viral infections and induce skin itching because of the increase in blood sugar and the obvious decline in immunity and disease resistance.

Urogenital system diseases: In patients with chronic nephritis, especially in patients with advanced uremia, the metabolites such as urotoxin and urea in blood cannot be excreted, but a large number of them remain in the body and are excreted with sweat, thus causing intractable itching all over the body, which is unbearable. Middle-aged and elderly women often suffer from vulvar itching due to irregular menstruation, increased leucorrhea, unclean vulva, ovarian lesions, or vulvar inflammation caused by trichomonas vaginalis and fungal infection.

Hematological diseases: polycythemia vera is often accompanied by itchy skin all over the body, some of which have burning sensation, which is aggravated in summer, even worse after taking a hot bath, and relieved after half an hour. Amazingly, aspirin can slow down the itching. About 15%-20% patients with iron deficiency anemia have systemic or local itching, which can be relieved after iron supplementation and anemia correction.

Central nervous system diseases: neurasthenia, cerebral arteriosclerosis, brain edema and brain tumor will lower the antipruritic threshold of central receptors, leading to itchy skin. What's even more amazing is that when the brain tumor infiltrates into the bottom of the fourth ventricle, it will cause severe and lasting itching of the skin near the nostril of the face, and then develop to the whole cheek.

Malignant tumor: Most tumors can cause itchy skin all over the body due to nerve endings stimulated by cancer cells and metabolites. In the early stage of gastric cancer and liver cancer, the whole body often itches slightly, and the itching intensifies with the progress of cancer. Lymphoma, such as mycosis fungoides and Hodgkin's disease, is accompanied by itchy skin all over the body. Rectal cancer and colon cancer often show anal pruritus; All kinds of leukemia, lung cancer and esophageal cancer are accompanied by itching.

Other causes of skin itching: drug-induced itching: more common in frail elderly patients, a variety of drugs used alternately. Many oral and injection drugs can cause itching in people with skin allergies, which is more likely to happen when combined with drugs.

Infectious pruritus: Itching mostly occurs in rural mountainous areas and other areas with poor sanitary conditions. It is caused by scabies infection and is mostly confined to fingers, toes and ankles. In severe cases, it affects the whole body and is difficult to cure.

Itching of drug addiction: drug addicts all suffer from "paranoid dermatoparasitic disease", that is, the feeling of insects crawling under the skin in hallucinations, which is manifested as itching of the skin, which is a skin illusion after drug addiction.

Therefore, whenever you suffer from persistent, recurrent and intractable pruritus, but you can't explain it satisfactorily with your skin, you should consider the possibility of the above diseases. Go to the hospital as soon as possible, find out the root cause, treat the symptoms and avoid future troubles.