[Safety and tolerance of single-dose botulinum toxin Type A treatment in 204 patients with spasticity and localized associated symptoms. Austrian and German botulinum toxin A spasticity study group]

Abstract

High dose oral anti-spastic medication is effective in the treatment of spasticity but has the disadvantage of frequent systemic side effects such as drowsiness and general weakness. Therefore, neurolytic and chemodenervation procedures are further therapeutic options, especially in cases of local spasticity. Apart from phenol blocks with the risk of persisting painful dysesthesia, botulinum toxin type A (BtxA) appears to be a safe and effective treatment. In 204 patients (mean age, 41.5 years [range 3-91 years]) with acute (n = 29, mean duration of disease 2.9 months [range, 1-6 months]) and chronic (n = 175, mean duration of disease 111 months [range, 7-500 months]) spasticity due to stroke, traumatic brain and spinal injury and other lesions of the upper motor neuron, the effects of single-dose BtxA treatment were studied. An overall dose of 181.2 units [range, 15-600 units] of BtxA (Botox) was injected in a mean of 3.3 [1-14] muscles per patient. Results were assessed using a modified Rating of Response to BtxA (RRB, Brin et al. 1995). The RRB includes a pre- and post BtxA assessment of the severity of spasticity-associated problems (patient's self-assessment), a rating of the current percentage of normal function in the region of the body selected for BtxA and a global rating of changes induced by BtxA. 191 (93.6%) patients demonstrated improvement over a mean of 7.7 weeks [1-36]; no deterioration was observed. Mean overall severity and function improved significantly (p < 0.001). No systemic or severe side effects were registered. Only in 5.9% of the patients were mild (n = 10) or moderate (n = 2) reversible adverse events reported. We conclude that BtxA injections are safe and effective in the treatment of local spasticity.