Efficacy of neurotropin in fibromyalgia: a case report.

Fibromyalgia is a refractory disorder that often necessitates long-term treatment. A 45-year-old woman has suffered from a stiff neck for 27 years and severe widespread pain for 4 years. Her visual analog scale (VAS), global-VAS, self-rating depression scale (SDS), and face scale were 48, 38, 42, and 15, respectively. She met the American College of Rheumatology 1990 criteria for the classification of fibromyalgia. Four tablets of Neurotropin (NT) per day alone were administered, and her pain was gradually alleviated over 3 weeks. Her heavy sensation of the body and morning stiffness had almost disappeared 5 months later. Her VAS was 40 after 6 months, but the subjective pain decreased to half that at the initial visit. Her global-VAS, SDS, and face scale were 0, 35, and 8, respectively. No adverse effects were observed. NT, a nonprotein extract from the inflamed skin of rabbits inoculated with vaccinia virus, is a commonly prescribed analgesic drug for chronic pain in Japan. One of the advantages of NT is its few and slight adverse effects. Because NT does not suppress the synthesis of prostaglandin, NT does not cause digestive ulcers. Recent studies suggest that the analgesic mechanism of NT is due to the activation of a descending pain inhibitory system in the brain. Two open studies have shown the efficacy of NT for fibromyalgia. In order to determine whether NT is effective for fibromyalgia, a rigid clinical study, such as a double-blinded, placebo-controlled study, is needed.