ABSTRACT
BACKGROUND: Tramadol hydrochloride is a centrally acting analgesic agent with two distinct mechanisms of action, a weak opioid agonist and an inhibitor of monoamine neurotransmitter reuptake, which produces significant analgesic effect synergistically. Though tramadol was approved in 1978 in Japan, it has rarely been used in clinical settings compared to foreign countries, e.g. Germany and USA. The aim of this study is to investigate effectiveness of oral tramadol for chronic non-malignant pain in Japan. METHODS: Tramadol was orally administered to patients with refractory non-malignant pain. Effects and adverse effects of tramadol were assessed about one month after the start of the administration. RESULTS: Out of 17 patients using tramadol daily, tramadol was found to be significantly effective in 4 patients (23.5%) and moderately effective in 8 patients (47.1%) from the viewpoint of pain relief as well as improvement of activities of daily livings. Side effects were reported by 7 patients (41.2%), which included nausea, constipation, and dizziness, but none of the side effects were serious. CONCLUSIONS: Tramadol is a useful option to treat non-malignant chronic pain, especially considering its very low abuse potential and a more acceptable side effect profile compared to non-steroidal anti-inflammatory drugs and opioids.
