Use of Botulinum Toxin for the Treatment of Raynaud Phenomenon.

Raynaud phenomenon (RP) is a vasospastic condition of the digital arteries that can cause pain, skin color changes, and functional limitations. Although botulinum toxin is not currently Food and Drug Administration-approved for the treatment of RP, it has been used in refractory RP and has generally been found to be well tolerated. At our institution, incobotulinumtoxinA (Xeomin) and abobotulinumtoxinA (Dysport) are commonly used. Here, we report our experience with the use of incobotulinumtoxinA (Xeomin) in the hand. We present 2 cases of patients with RP in bilateral hands who presented for Botox injections after failure of conservative and medical therapy. In both cases, incobotulinumtoxinA (Xeomin) was used. A week later, both patients experienced various distributions of severe muscle weakness, including intrinsic, thenar, and hypothenar muscle weakness, which did not improve during the subsequent 4 weeks. Although safe, further studies are needed to assess the diffusion of various botulinum toxin A formulations, especially in the hands, as prolonged intrinsic, thenar, and hypothenar muscle weakness can be detrimental to patients.