How does the hot weather make the skin often feel itchy?

Skin itching is nonspecific and can be a symptom of many diseases. Your father's symptoms may be pruritus, and there are 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 we should pay attention to observing allergic factors and checking out some diseases in our lives. Antihistamine drugs can be used in treatment, and second-generation antihistamines such as ebastine or mizolastine can be selected. It is recommended to use drugs under the guidance of a doctor. Some external emollients and antiallergic ointments can also be added. Use less alkaline soap when taking a bath.

itchy skin

itching is generally considered to be caused by skin diseases. The most common is senile pruritus in winter. The reason is that due to hypogonadism and endocrine function, sebaceous glands and sweat glands atrophy in the elderly, so that the skin is too dry, and the nerve terminal receptors distributed in the shriveled skin are aging and degenerating, sending out 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 first or at the same time, are mostly signs of various diseases, so you should go to the hospital in time and treat it early to avoid serious illness.

digestive system diseases: common hepatobiliary diseases, including obstructive jaundice, hemolytic jaundice, etc., cause systemic skin itching due to the increase of bile salt concentration in serum and skin, which stimulates nerve endings. Pregnant women's endocrine disorder during pregnancy will lead to "pregnancy pruritus", because estrogen and progesterone increase during pregnancy and disappear automatically after delivery.

Endocrine system diseases: About 19% of patients with hyperthyroidism and hypothyroidism have skin itching, but there are differences between them. The itching of hyperthyroidism appears earlier, and it is mostly aggravated in summer because the skin of hyperthyroidism is moist. However, the itch of "hypothyroidism" appears later and develops slowly, and the skin is drier and rougher, which is more likely to induce itching in winter. Because of the increase of blood sugar, diabetic patients' immunity and disease resistance are obviously reduced, and they are more susceptible to bacterial and viral infections and induce itchy skin.

Urogenital system diseases: Patients with chronic nephritis, especially in the late stage (uremia stage), are unable to excrete metabolites such as urotoxin and urea in their blood, but a large number of them remain in the body and are excreted with sweat, thus causing systemic stubborn itching and unbearable itching. Middle-aged and elderly women often suffer from vulvar pruritus 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 mostly accompanied by systemic skin itching, some of which are burning and stinging, aggravated in summer, even worse after hot bath, and relieved after half an hour. The miracle is that aspirin can slow down this itching. About 15%-2% of patients with iron deficiency anemia have systemic or local itching, which can be relieved after iron supplementation and anemia correction.

diseases of central nervous system: neurasthenia, cerebral arteriosclerosis, brain edema and brain tumor will lower the antipruritic threshold of central receptors, leading to itchy skin. What is 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 systemic skin itching due to nerve endings stimulated by cancer cells and metabolites. Gastric cancer and liver cancer often itch slightly all over the body in the early stage, and the itching intensifies with the progress of cancer. Lymphatic cancers such as mycosis fungoides and Hodgkin's disease are all accompanied by systemic skin itching. Rectal and colon cancer often show anal pruritus; Various leukemia, lung cancer and esophageal cancer are accompanied by generalized itching.

Skin pruritus caused by other reasons: drug-induced pruritus: it is more common in old patients who are frail and sick, and many drugs are used alternately. Many oral and injection drugs can cause itching in people with skin allergies, and it is more likely to happen when they are combined with drugs.

infectious itching: itch caused by sarcoptes scabies infection often occurs in rural mountainous areas and other areas with poor sanitary conditions, which are mostly confined to the fingers, toes and ankles. In severe cases, it spreads all over the body and is difficult to cure.

pruritus due to drug addiction: drug addicts suffer from "delusional dermatoparasitic disease", that is, the feeling that there are insects crawling under the skin in hallucinations, which is manifested as itchy skin and uncomfortable skin. This is a skin illusion after drug addiction.

Therefore, when patients with persistent, recurrent and intractable skin pruritus cannot be satisfactorily explained by skin, the possibility of the above diseases should be considered. We should go to the hospital as soon as possible to find out the root cause of the disease and treat it symptomatically to avoid future troubles.