I do not know if the compound is dialysable but would guess it is since it crosses the glomerular membrane in individuals with normal kidneys. The serum level will return to normal in 2 days. Charcoal is odorless and tasteless, but the grittiness may be a little unpleasant. Our patients recommend taking the charcoal in juice, especially grape juice. The reason charcoal works is the level of porphyrins in the enterohepatic circulation is about 10 times that found in serum.
Charcoal absorbs the prophyrins and they are then eliminated in the feces.
Removing the excess porphyrins doesn't alleviate the overproduction, so for long term treatment, bloodletting is still treatment of choice for most patients. However, there are occasional patients who are already anemic, or for whom blood letting is otherwise impractical, and oral charcoal is helpful. If you are considering doing this for a long period of time, your patient may need some vitamin supplementation, otherwise it seems to be safe. Use activated charcoal powder and not the syrup that is used in emergency rooms. We managed such a case by depleting the iron with phlebotomy and continuing the epogen.