title: Eosinophilic exudative pleural effusion after initiation of tizanidine treatment: a case report.
abstract: In this case report, we present a 42-year-old man with history of chronic low back pain after a work-related injury. The patient failed multiple therapeutic modalities both conservative and interventional, including numerous spinal injections and placement of a spinal cord stimulator. Finally, an intrathecal morphine pump was placed to control his pain in addition to oral pain medications. The course of the treatment included adding a muscle relaxant, tizanidine (Zanaflex), to control spasms in the lower extremities. Six weeks after starting tizanidine, a large pleural effusion was noted incidentally on a computerized tomography scan of the thoracic and lumbar spine. The patient underwent work-up for the pleural effusion; all tests came back negative. Finally, a drug reaction to tizanidine was suspected. The drug was discontinued, and 4 weeks later the pleural effusion resolved.
authors.affiliation: Department of Anesthesiology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Ghassan
authors.initials: G
authors.lastname: Moufarrege
authors.forename: Evan
authors.initials: E
authors.lastname: Frank
authors.forename: Donna D
authors.initials: DD
authors.lastname: Carstens
mesh_terms: D000328:Adult; D000700:Analgesics / Q000009:adverse effects*; D002908:Chronic Disease; D003000:Clonidine / Q000009:adverse effects* / Q000031:analogs & derivatives*; D004802:Eosinophilia; D006801:Humans; D017116:Low Back Pain / Q000188:drug therapy*; D008297:Male; D010996:Pleural Effusion / Q000139:chemically induced* / Q000473:pathology
chemical_list: D000700:Analgesics; C023754:tizanidine; D003000:Clonidine