Tramadol tablets are representative of central analgesic drugs. Tramadol is more effective than ibuprofen, anti-inflammatory pain, paracetamol, celecoxib and other NSAIDs in relieving pain, and is mainly used for cancer pain, post-operative pain and various acute and chronic pains of moderate degree. Side effects such as sweating, dizziness, nausea, vomiting, loss of appetite and difficulty in urination may occur during taking the drug, and a few patients may also experience palpitations, bradycardia, or upright hypotension and other uncomfortable symptoms.