28 hepatocellulære neoplasmer i et carcinogenicitetsstudie på mus anses for at være artsbestemt, non - genotoksisk respons i forbindelse med langtidsbehandling med høje doser af leverenzyminduktorer.
Thyroid gland tumours found in a rat carcinogenicity study and hepatocellular neoplasms found in a mouse carcinogenicity study are considered to be species-specific, non-genotoxic responses associated with long-term treatment with high doses of hepatic enzyme inducers.