A Case of Acute Colchicine-induced Myopathy with Myotonia in Behcet Disease

Colchicine has been used in the treatment of autoimmune diseases such as Behcet disease. Long-term use of colchicine can cause vacuolar myopathy on rare occasions. We report colchicine-induced myopathy with myotonia in Behcet disease. A 34-year-old man with Behcet disease presented progressive proximal weakness, myalgia, and difficulty in relaxation of grip after increasing the dosage of colchicine. Electrophysiological findings showed myotonic myopathy. Muscle biopsy revealed vacuolar myopathy. His symptoms were resolved with the discontinuation of colchicine.