Possible Interaction: Carnitine and Valproic Acid

“An inverse correlation was found between serum concentrations of carnitine and duration of treatment in patients treated with VPA.”

“The mean total and free carnitine were significantly lower in both the VPA monotherapy and polytherapy groups compared with the controls.”

“Nowhere has the popularity of carnitine been more evident than in the treatment of children taking valproic acid , which causes in some children a depression of free carnitine levels.”

“Plasma carnitine concentrations were lower and blood ammonia values were higher in patients treated with valproic acid than in the untreated patients and control subjects.”

“It is postulated that carnitine supplementation may increase the β-oxidation of VPA , thereby limiting cytosolic ω-oxidation and the production of toxic metabolites that are involved in liver toxicity and ammonia accumulation.”

“ VPA inhibits the biosynthesis of carnitine by decreasing the concentration of α-ketoglutarate and may contribute to carnitine deficiency.”

“The anticonvulsive drug, valproic acid (VPA), inhibits the biosynthesis of carnitine , and may contribute in this way to carnitine deficiency associated with VPA therapy.”

“The metabolites of VPA interfere with urea cycle and cause deficiency in carnitine leading to increase in ammonia levels.”

“ Carnitine levels were significantly low in patients under valproic acid therapy , however they were not found to be correlated with MDA, 8-OHdG or LFTs.”

“Several studies have shown that carnitine supplementation in patients receiving VPA to result in subjective and objective improvements and to prevent VPA-induced hepatotoxicity and encephalopathy, in parallel with increases in carnitine serum concentrations.”

“ Carnitine is a commonly used antidote for acute intoxication of valproic acid , but is not a therapeutic option for management of chronic adults with adverse effects related to valproic acid.”

“Administration of not only valproic acid but also other anti-epileptic drugs was found to cause a significant decrease of free carnitine levels after adjusting the nutritional intake of carnitine.”