Patients with sudden swelling and pain in the fingertips may be caused by improper sleeping posture or prolonged hand-carrying of heavy objects, resulting in prolonged compression of the fingers, which can usually be relieved on its own after lifting the compression. In addition, daily life is also common in mosquito bites, finger trauma, etc., but does not exclude a small number of patients are rheumatoid arthritis, kidney disease and other causes: 1, mosquito bites: mosquito bites on the fingers, resulting in acid and bacteria, etc. into the patient can lead to sudden swelling of the fingertips, painful symptoms, may also be accompanied by itching. Patients need to pay attention to avoid scratching the affected area, mild cases can heal on their own. If the itching is more serious or swelling is more obvious, you can apply erythromycin ointment, gentamycin eye ointment and other drugs, or take cetirizine, loratadine and other antihistamines to relieve the symptoms; 2. Trauma: If the patient’s fingers are smashed, sprained and other trauma, it may lead to local soft tissue damage, finger fractures or infection triggered by purulent dactylitis, and then the symptoms of sudden swelling and pain in the fingertips. Cephalosporin, penicillin antibiotics can be used for treatment, if necessary, incision and drainage, if there is a fracture usually also need to be fixed treatment or surgery; 3, rheumatic immune diseases: common rheumatoid arthritis, rheumatoid arthritis, gout, etc., patients can appear sudden swelling of the fingertips, painful symptoms, and often occurs in the morning. Anti-rheumatic treatment with salicylic acid preparations, glucocorticoids, etc. is required as prescribed by the doctor. 4. Kidney diseases: If the patient suffers from acute glomerulonephritis, renal failure and other kidney diseases, as the kidney function is impaired, it may cause systemic edema, so it may spread to the fingertips and appear the symptoms of sudden swelling and pain. Relevant tests need to be performed and treatment should be tailored to different kidney disease types. Some people who use their hands for a long time may develop tenosynovitis. Acute septic tenosynovitis can occur with swelling of the fingertips, often accompanied by redness, swelling and pain. Patients with nail infections can also present with swollen fingertips, usually preceded by excessive nail clipping.