The evidence for noncosmetic uses of botulinum toxin
Botulinum toxin has been studied for a variety of uses beyond the cosmetic. Here’s what you need to know about which uses are worth considering for your patient.
PRACTICE RECOMMENDATIONS
› Do not use botulinum toxin for episodic migraine, tension headache, or cluster headaches. B
› Consider off-label use of botulinum toxin for select patients with occipital and trigeminal neuralgia, gastroparesis, vaginismus, benign prostatic hypertrophy, neonatal brachial plexus palsy, post-stroke spasticity, and hemifacial spasm. B
› Consider the use of botulinum toxin as an adjunct in chronic low back pain management. B
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
Hemifacial spasm is an involuntary, brief, irregular unilateral (sometimes bilateral) spasm of the face in the distribution of the facial nerve. Injections with BoNT-A have been deemed effective by the American Academy of Neurology.23 A 16-year retrospective study examined the efficacy and adverse effects of BoNT-A in the treatment of hemifacial spasm in 113 patients with a mean age of 63.1 years; it demonstrated high efficacy and mild temporary adverse effects.24 The duration of improvement averaged 16 weeks; pretarsal injections had better results than preseptal injections; and there were no differences between the commercial brands.
Blepharospasm is a focal dystonia marked by excessive blinking and involuntary eye closures due to overexcitability of orbicularis oculi and periocular muscles, and BoNT-A is the treatment of choice.5,25 A retrospective review of 19 patients with blepharospasm who were treated with BoNT-A for more than 5 years found that BoNT-A is a stable and effective treatment with an adverse event rate of 4%. Additionally, there were no differences found in clinical efficacy between the 4 BoNT-A brands on the market.25
Laryngeal tics can cause significant psychosocial distress for patients. This condition is characterized by involuntary, recurrent rhythmic sounds that are often preceded by premonitory urges that are relieved by the behavior. An open-label, uncontrolled, confirmatory study with 30 subjects showed that bilateral vocal cord BoNT-A injections resulted in 93% improvement in vocal tics.26 A subsequent study highlighted case histories of 2 patients with laryngeal tics who received thyroarytenoid muscle BoNT-A injections and had marked reduction in symptoms and premonitory sensations.27 Although these small studies have suggested possible effectiveness of BoNT-A for laryngeal tics, there is no high-quality evidence.
Urologic disorders
Overactive, idiopathic overactive, or neurogenic bladder causes increased urinary frequency, urgency, and nocturia without infectious etiology; they can be a result of neurologic dysregulation, detrusor overactivity, or idiopathic causes. Intravesical BoNT-A injection of 100 to 300 U has been found effective for symptoms refractory to anticholinergic and lifestyle therapy, with increased cystometric capacity (229.1 to 427 mL, P < .00001), decreased maximum detrusor pressure (60.7 to 26.1 cm H2O, P < .00001), and resolution of urgency in 87% of patients (P < .001).28
Interstitial cystitis, also known as painful bladder syndrome, is characterized by reduced bladder emptying, urethral pressure, and residual urine pressure, with symptoms of increased urinary frequency without infection. Intravesicular BoNT-A injections have not consistently been effective in treatment of this condition.28
Continue to: Dysfunctional voiding, urethral sphincter overactivity, and Fowler syndrome
