Botulinum toxin for chronic pain: What's on the horizon?
Botulinum toxin has proven safe and effective when used correctly. This review examines the evidence that could support its expanded use.
PRACTICE RECOMMENDATIONS
› Consider botulinum toxin (BoNT) for patients with headache, spasticity, or cervical dystonia, as the FDA has approved BoNT for pain relief in these conditions. A
Strength of recommendation (SOR)
A Good-quality patient-oriented evidence
B Inconsistent or limited-quality patient-oriented evidence
C Consensus, usual practice, opinion, disease-oriented evidence, case series
BoNT is contraindicated in those with a history of a previous anaphylactic reaction to BoNT. Patients with known hypersensitivity to BoNT, including those with neuromuscular junction diseases and anterior horn disorders, should be considered for other forms of treatment due to the risk of an exaggerated response. No adverse events have been recorded in regard to pregnancy and lactation, although these remain a potential contraindication.3,4,6
Taking a closer look at current indications
Headaches
Chronic migraine (CM) is defined by the International Headache Society as at least 15 days per month with headaches and 8 of those days with migraine features. BoNT has been FDA approved for treatment of CM since 2011. This was based on 2 large, double-blind, randomized, placebo-controlled trials that showed a significant reduction from baseline for headaches and migraine days, total time, and frequency of migraines.7,8
Subsequent studies have continued to show benefit for CM treatment. In a recent Cochrane systematic review and meta-analysis, it was determined that BoNT can decrease frequency of CM by 2 days per month, and it is recommended by several organizations as a treatment option for CM.9
Low-quality evidence has not shown benefit for tension-type headaches. However, further research is warranted, especially for chronic tension-type headache, which is defined as daily tension headaches.10
Spasticity
Spasticity is caused by an insult to the brain or spinal cord and can often occur after a stroke, brain or spinal cord injury, cerebral palsy, or other neurologic condition.11 BoNT was initially FDA approved in 2010 for treatment of upper limb spasticity in adults, although it had been used for treatment for spasticity for more than 20 years prior to that. It currently is approved for upper and lower spasticity in adults and recently was expanded to include pediatrics.12
Continue to: A small case series...
