the development of phospholipoidosis, with scaly inclusions in hepatocytes, Schwann cells and other tissues which could point to the cause of peripheral neuropathy. The peripheral neuropathy is often but not always permanent. The risk of perhexiline toxicity is reduced by therapeutic drug monitoring (TDM). The simplest way to rectify the problem of perhexiline toxicity is to stop administering the drug and allowing the plasma concentration to fall; once the concentration has reached the desired level resume the treatment at a lower dose. Most PMs should receive doses of no more than 50mg/week of perhexiline. References Antianginals CYP2D6 inhibitors Hepatotoxins Piperidines