The influence of porphyrogenic drugs on the glyoxalase enzymes.

A variety of drugs, known to induce acute attacks in porphyric patients has been found to inhibit the glyoxalase pathway. Glyoxalase I is competitively inhibited by sulphadimidine, oxytetracycline, chloramphenicol, etc. Allylisopropyl acetamide (AIA) seems to inhibit glyoxalase II. This inhibition could play a contributing role in the overproduction of porphyrins in porphyria and thus help explain the mechanism of induction of porphyric attacks. The results indicate, that the Heme pathway and the glyoxalase cycle are closely connected.