A Case Report and Evaluation of Pirmenol Toxicity Appeared with Liver Injury

A 56-year-old woman inpatient that had been administrated warfarin, digoxin, verapamil and disopyramide after undergoing surgery for a mitral and aortic valve replacement associated with artrial fibrillation received a 300mg daily dose of disopyramide therapy before and after the operation. Although the serum disopyramide concentration was within the normal therapeutic range, dry mouth appeared as a side effect. Disopyramide was thus changed to pirmenol. The trough level of pirmenol was 2.1μg/mL at seven days after starting pirmenol therapy at the dose of 300 mg/day, and the dose was there after decreased to 200mg/day. About two weeks after pirmenol therapy was started, liver injury was observed. At approximately 30 days after pirmenol administration was stopped, the liver function returned to a normal level.On the other hand, according to recent reports pirmenol was suggested to show a high level in the liver. The reported levels of pirmenol were also similar to for amiodarone and aprindine, which are both well known to induce side effect in the liver. Therefore, one of the reasons that pimenol induced liver injury may be due to its high levels in the liver.