tropisetron and Low-Back-Pain

The activation of 5-hydroxytryptamine-3 (5-HT-3) receptors in spinal cord can enhance intrinsic spinal mechanisms of central hypersensitivity, possibly leading to exaggerated pain responses. Clinical studies suggest that 5-HT-3 receptor antagonists may have an analgesic effect. This randomized, double-blind, placebo-controlled crossover study tested the hypothesis that the 5-HT-3 receptor antagonist tropisetron attenuates pain and central hypersensitivity in patients with chronic low back pain. Thirty patients with chronic low back pain, 15 of whom were women (aged 53 ± 14 years) and 15 men (aged 48 ± 14 years), were studied. A single intravenous injection of 0.9% saline solution, tropisetron 2mg, and tropisetron 5mg was administrated in 3 different sessions, in a double-blind crossover manner. The main outcome was the visual analogue scale (VAS) score of spontaneous low back pain before, and 15, 30, 60, and 90 minutes after drug administration. Secondary outcomes were nociceptive withdrawal reflexes to single and repeated electrical stimulation, area of reflex receptive fields, pressure pain detection and tolerance thresholds, conditioned pain modulation, and area of clinical pain. The data were analyzed by analysis of variance and panel multiple regressions. All 3 treatments reduced VAS scores. However, there was no statistically significant difference between tropisetron and placebo in VAS scores. Compared to placebo, tropisetron produced a statistically significant increase in pain threshold after single electrical stimulation, but no difference in all other secondary outcomes was found. A single-dose intravenous administration of tropisetron in patients with chronic low back pain had no significant specific effect on intensity of pain and most parameters of central hypersensitivity.

Topics: Adult; Aged; Chronic Pain; Cross-Over Studies; Double-Blind Method; Female; Humans; Hyperalgesia; Indoles; Low Back Pain; Male; Middle Aged; Placebos; Reaction Time; Serotonin 5-HT3 Receptor Antagonists; Treatment Outcome; Tropisetron; Young Adult

Various pathophysiological processes can lead to chronic back pain, which necessitates a differentiated therapeutic approach. In addition, psychic and psychosocial processes may influence the clinical picture.. Twenty-five patients with chronic back pain were enrolled in the study. Patients suffering from psychosocial stresses and depressions were excluded from the study. The patients with painful tendinopathies and myofascial pain syndromes were treated with local injections of 5-10 mg tropisetron, and patients with degenerative processes were treated for 5 days with an intravenous (i.v.) bolus injection of 5 mg tropisetron (Navoban). Before treatment and 7 and 14 days later, the visual analog pain scale was filled in. The long-term drug therapy could be continued.. There was a highly significant pain reduction with a very potent effect both in the locally treated group and in the intravenously treated group. Most of the patients could discontinue or reduce their long-term therapy with non-steroidal anti-inflammatory drugs or analgesics.. A marked improvement in pain could be achieved in an open study by treating back pain of a primarily somatic nature with the 5-HT3 receptor antagonist tropisetron. A reduction in pain of > or =50% was reported by 76% of the patients. These results should be substantiated by the corresponding randomized, placebo-controlled, double blind studies that are needed to investigate the true benefit of treating back pain with 5-HT3 receptor antagonists.

Topics: Adult; Aged; Chronic Disease; Female; Humans; Indoles; Low Back Pain; Male; Middle Aged; Serotonin Antagonists; Tropisetron

Topics: Chronic Pain; Female; Humans; Hyperalgesia; Indoles; Low Back Pain; Male; Serotonin 5-HT3 Receptor Antagonists; Tropisetron