Botulinum Toxin in the Long-Term Treatment of Refractory Raynaud’s Phenomenon.

Raynaud’s phenomenon is an exaggerated physiological response of blood vessels in the distal extremities to emotional stress and cold. It can be idiopathic or secondary to a connective tissue disorder, such as scleroderma or systemic lupus erythematosus. Treatment for Raynaud’s phenomenon consists primarily of lifestyle modifications; if unsuccessful, pharmacotherapy with dihydropyridine calcium channel blockers can be added. Botulinum toxin (BTX-A) is a neurotoxic protein produced by Clostridium botulinum spores. While most widely known for its cosmetic use, BTX-A has many therapeutic utilities due to its ability to inhibit multiple neurotransmitters. In this report, we present a patient with Raynaud’s phenomenon refractory to standard therapies whose symptoms resolved after treatment with BTX-A. Follow-up with the patient after one and five years showed no relapse or recurrence of symptoms. J Drugs Dermatol. 2019;18(9):943-945.