Dialysis Common toxins that may require dialysis or hemoperfusion include Ethylene glycol Lithium Methanol Salicylates Theophylline These therapies are less useful if the poison is a large or charged (polar) molecule, has a large volume of distribution (ie, if it is stored in fatty tissue), or is extensively bound to tissue protein (as with digoxin, phencyclidine, phenothiazines, or tricyclic antidepressants).