A comparative study of α-mercaptopropionylglycine (α-M P G) as a therapeutic chelating agent for excess tissue iron in the liver with commercially available drugs was undertaken. The drugs used for the compari on were B A L, penicillamine, sodium dithiocarbamate and desferrioxamine B. The materials studied were 11 cases of moderate to severe hepatic hemosiderosis, either primary or secondary, diagnosed with needle liver biopsy specimens. The results were as follows:
1) The decrease of serum iron, disappearance or reduction of stainable tissue iron in the liver, depigmentation of the skin were induced by parenteral or oral administration of α-M P G at the daily dosis of 200 to 450 mg for 2 to 6 months. The phenomena were explained as the results of a chelating effect of α-M P G on excess tissue iron in the liver.
2) No significant effect on essential serum electrolyte such as potassium, calcium was observed during the α-M P G administration.
3) No undesirable side effect was noted, therefore, a prolonged administration was practicable.
4) Iron excretion into the urine was less intense than that with dithiocarbamate, however, it was more intense than that with penicillamine. On the other hand, iron excretion into the feces was observed in the decreasing order with dithiocarbamate, desferrioxamine B, penicillamime, and α-M P G. The daily excretion of iron into urine amounted 2 to 4 mg with α-M P G.