Porphyria Educational Services
PORPHYRIA EDUCATIONAL SERVICES
Bulletin Vol. 1 No. 30 July 25, 1999
Focus: Hematin Panhematin or
Hematin for short, is used for intervention
therapy in acute attacks of porphyria. Hematin is often
administered after 24 to 30 hours of glucose has been
administered and has not brought an acute attack under control.
Panhematin is manaufactured by the Abbott Laboratories. Hemin for
injection is an enzyme inhibitor derived from processed red blood
cells.This used for injection was known previously as hematin.
The term hematin has been used to describe the chemical reaction
product of hemin and sodium carbonate solution. Hemin is an iron
containing metalloporphyrin. Chemically hemin is represented as
chloro
(7,12-diethenyl-3,8,13,17-tetramethyl-21H,23H-porphine-2,18-dipropanoato
(2-)-N21,N22,N23,N24) iron for all of porphyrics with a chemistry
background!
The hematin is a sterile, lyophilized powder suitable for
intravenous administration after reconstitution. The bad
"rap" that hematin has been given by many physicians is
that it will cause coagulation problems in patients, leaving them
with blood clots and possible pulmonary emboli.
The reasons for this concern is that often this powder substance
has not been properly mixed, and also because it has not been
used within a short time of mixing. It is vital that the
substance be properly mixed and that it is immiediately
administered by iv infusion.
Each dispensing vial of hematin contains the equivalent of 313 mg
hemin, 215 mg sodium carbonate and 300 mg of sorbitol. The pH may
have been adjusted with hydrochloric acid; the product contains
no preservatives. When mixed as directed with Sterile Water for
Injection, USP, each 43 ml provides the equivalent of
approximately 301 mg hematin (7 mg/ml).
Outside of the United States a purer refined heme substance known
as heme arginate is readily used. It is currently used in
clinical trials at the University of Texas Medical School in
Galveston, TX, by Dr. Karl Anderson, a leading porphyria
researcher. No expected date for FDA approval in the U.S. has
been announced.