Tramadol is a pain reliever. It is an opioid drug that works in the brain to change how your body feels and responds to pain. Tramadol should only be taken exactly as prescribed by your doctor. Buy Tramadol Online is an immediate-release opioid analgesic indicated for the management of moderate to moderately severe pain. Tramadol works in the brain, alters the body's response toward pain and manages symptoms. The most commonly reported side effect was nausea, which occurred in about 10% of patients who received tramadol hydrochloride extended-release capsules compared to 7% of those receiving placebo.