Possible Interaction: Levodopa and Methionine

“A possible mechanism by which levodopa can function in changing protein synthesis is transmethylation: “Siphoning off” of labile methyl groups from methionine , the chief methyl source in tissues, is a necessary accompaniment of levodopa therapy.”

“Subcutaneous injections of 500 mg/kg l-Dopa daily for 8 days increased the concentrations of isoleucine, methionine , threonine and tyrosine.”

“If the metabolism of the circulating amino acid in humans is similar to that of mice, it can be calculated that the amount of methionine needed to O-methylate the doses of L-dopa commonly used in parkinsonian patients may be greater than the average daily methionine intake.”