The swelling next to the thumb may involve a variety of causes, and it is not possible to make an accurate diagnosis of this symptom alone, so it is advisable to visit a hospital for a clear diagnosis and appropriate treatment. Generally speaking, common causes include strain, injury, arthritis, swelling, infection, etc., and the appropriate treatment should be taken depending on the cause. If the injury or strain causes a local hematoma or inflammatory reaction, anti-inflammatory and analgesic treatment, blood circulation and blood stasis can be applied externally with Fotarin emulsion, orally with Tongluo Kai Paralysis tablets or local physical therapy to relieve the symptoms. If it is caused by infection, local symptoms of redness, swelling, heat and pain will be treated with antibiotics and, if necessary, surgical incision and drainage. If it is caused by joint inflammation, medication will be taken depending on the cause, usually involving the application of non-steroidal anti-inflammatory drugs and, in severe cases, immunomodulatory agents. If there is a local swelling, such as the more common mucous cyst, it can also cause swelling and often requires surgical treatment. The diagnosis should first be clarified before talking about treatment.