Long-term treatment of cervical dystonia with botulinum toxin A: efficacy, safety, and antibody frequency. German Dystonia Study Group

J Neurol. 1999 Apr;246(4):265-74. doi: 10.1007/s004150050345.


Data from 616 patients suffering from idiopathic cervical dystonia were analyzed to determine the efficacy and safety of treatment with botulinum neurotoxin type A (BoNT/A). Since the specific purpose of this study was to determine the long-term effects of this treatment, the analysis focused specifically on the patients (n = 303) having received six or more injections. Statistical analysis of a standardized documentation showed sustained significant benefit as measured by a disease severity score independent of the type of cervical dystonia. Furthermore, pronounced individual differences were found in response to this treatment although initial clinical scores and doses of BoNT/A were similar. There was no indication of previously unknown adverse events, the only risk being the development of serum antibodies against the toxin. As in previous studies on short-term effects of BoNT/A treatment, the most frequent adverse event was dysphagia, which occurred on average 9.7 days after injection and lasted on average 3.5 weeks. While secondary nonresponse was seen in approx. 5% of patients, antibody tests revealed neutralizing serum antibodies in only 2%. On the basis of the present data, therapy of cervical dystonia with BoNT/A seems to be safe and yields good stable results even after 5 years of treatment.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Botulinum Toxins, Type A / administration & dosage
  • Botulinum Toxins, Type A / adverse effects
  • Botulinum Toxins, Type A / therapeutic use*
  • Deglutition Disorders / chemically induced
  • Dystonia / drug therapy*
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Neck Muscles* / physiopathology
  • Neuromuscular Agents / administration & dosage
  • Neuromuscular Agents / adverse effects
  • Neuromuscular Agents / therapeutic use*
  • Treatment Outcome


  • Neuromuscular Agents
  • Botulinum Toxins, Type A