Only traces of unchanged drug are excreted through the bile into the feces. As an adjunct to rest, physical therapy and other measures for the relief of discomfort associated with acute, painful musculoskeletal conditions. In patients hypersensitive to either chlorzoxazone, acetaminophen or codeine. Parafon Forte C8 may contain metabisulfite, a sulfite that may cause allergic type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite sensitivity in the general population is unknown and probably low.
Sulfite sensitivity is seen more frequently in asthmatic than in nonasthmatic people.
If a sensitivity reaction occurs such as urticaria, redness, or itching of the skin, the drug should be stopped. There have been reports of liver damage associated with the use of chlorzoxazone-containing products. If any signs or symptoms suggestive of liver dysfunction are observed, the drug should be stopped. Furthermore, narcotics produce adverse reactions which may obscure the clinical course of patients with head injuries. Drowsiness can occur with the use of Parafon Forte C8.