HAEM IS THE IRON PROTOPORPHYRIN CONSTITUENT OF HAEMOGLOBIN AND IS RESPONSIBLE FOR ITS COLOUR AND OXYGEN-CARRYING CAPACITY. IT IS USED IN THE MANAGEMENT OF PORPHYRIAS. HAEM IS GIVEN INTRAVENOUSLY AS ITS DERIVATIVES, ALTHOUGH THERE IS SOME CONFUSION OVER THEIR TERMINOLOGY. THE NAMES HAEMATIN (HEMATIN) AND HAEMIN (HEMIN) HAVE BEEN USED INTERCHANGEABLY ALTHOUGH CHEMICALLY HAEMATIN IS THE HYDROXY DERIVATIVE, FORMED BY THE REACTION OF HAEMIN AND SODIUM CARBONATE IN SOLUTION. THE ARGININE SALT (HAEM ARGINATE; HAEMIN ARGINATE; HEME ARGINATE) IS REPORTED TO BE MORE STABLE.
SPECIFIC THERAPY IS AIMED AT SUPPRESSING THE HAEM BIOSYNTHETIC PATHWAY, TO PREVENT FURTHER ACCUMULATION OF PRECURSORS. HAEM, GIVEN AS EITHER HAEMATIN OR HAEM ARGINATE, IS THE MOST EFFECTIVE TREATMENT AND SHOULD BE GIVEN AS SOON AS POSSIBLE AFTER ONSET OF THE ATTACK; IT PRODUCES FEEDBACK SUPPRESSION OF THE BIOSYNTHETIC PATHWAY.