Tramadol extended-release capsules or tablets relieve pain by acting on the central nervous system (CNS). Tramadol works directly on opioid receptors in the CNS to inhibit how nerves communicate pain between the brain and the body (central nervous system). As a result, tramadol alters the response of pain receptors and how the body responds to pain. Buy Tramadol Online. It is effective for treating acute pain; however, your doctor may prescribe it for chronic diseases such as arthritis, gout, and back pain in some cases.