Immediate allergic reaction to thiocolchicoside confirmed by skin testing and basophil activation test: A case report and literature review

Background Thiocolchicoside is a muscle relaxant, anti-inflammatory, and analgesic. Administered orally, intramuscularly, or topically, this drug is used in the symptomatic treatment of muscular spasms and rheumatologic disorders. Despite its extensive use, thiocolchicoside is a very rare sensitizer. Objective To evaluate IgE-mediated reaction to thiocolchicoside by basophil activation test. Methods Allergological work-up with skin prick tests, intradermal tests and basophil activation test with thiocolchicoside. Results We report the first case of immediate reaction to thiocolchicoside confirmed by basophil activation test in addition to positive skin tests. Conclusions BAT can be considered a complementary diagnostic tool to demonstrate an IgE-mediated reaction also for muscle relaxant drugs.