[L-tryptophan. An essential amino acid for structural and functional metabolism].

Since the nineteen-sixties, L-Tryptophan has been used with success to treat depressive states and sleep disorders. When, in 1989, the substance was suspected of causing severe adverse reactions (EMS), approval for its use was initially suspended. It has since been shown that the undesired side effects were due not to L-Tryptophan itself, but to contaminations of the basic substance, and the suspension of approval was therefore lifted. In September 1996, L-Tryptophan was re-introduced onto the market as Ardeytropin. The present paper takes a look at the substance L-Tryptophan and discusses in particular its biochemical significance and its biokinetics/pharmacokinetics. The pharmacological basis for the use of L-Tryptophan to treat sleep disorders and depression is examined.