Efficacy of high doses of botulinum toxin A for treating provoked vestibulodynia

Summary Background  Provoked vestibulodynia is difficult to treat. The beneficial effects of botulinum toxin A are being considered because of the muscular anomalies observed in this pathology. Objective  To evaluate the efficacy of botulinum toxin A in the treatment of provoked vestibulodynia. Methods  Patients aged between 18 and 60 years presenting with provoked vestibulodynia (according to the 2003 International Society for the Study of Vulvar Disease classification) received 50 U of botulinum toxin A bilaterally in the bulbospongiosus muscle under electromyographic monitoring. Pain was evaluated by a visual analogue scale (VAS), quality of life was evaluated by the Dermatology Life Quality Index and sexual function by the Female Sexual Function Index. Results  Twenty patients received the injections. Sixteen patients presented with a muscular hyperactivity on electromyography. After 3 months, 80% of the patients improved in terms of pain. Mean ± SD VAS values significantly decreased from 8·37 ± 1·22 (range 4·5–10) to 2·57 ± 2·67 (0–9; P < 0·0001) at month 3 and to 3·90 ± 2·92 (0–9; P < 0·001) at month 6. Quality of life and sexual function improved significantly during the first 6 months (P < 0·0001). After 3 months, 13 patients (out of 18 for whom intercourse was not possible before the injections; 72%) were able to have sexual intercourse. Conclusion  Botulinum toxin A seems to be an effective and safe treatment for provoked vestibulodynia; 100 U botulinum toxin A significantly reduced pain 3 and 6 months after injections without side-effects. The treatment also improved quality of life and sexual function of patients. Botulinum toxin A appears to be a promising option for managing sexual pain disorder.