Acute hyperkalemia associated with intravenous epsilon-aminocaproic acid therapy.

Epsilon-aminocaproic acid (Amicar) is used to treat severe hemorrhage refractory to usual medical management. This antifibrinolytic drug has been associated with a number of renal complications. However, there are no descriptions of this medication causing hyperkalemia. This report describes the development of hyperkalemia in a patient with underlying chronic renal insufficiency treated with intravenous epsilon-aminocaproic acid. The patient, who underwent coronary artery bypass grafting, had no other obvious cause for the acute increase in serum potassium concentration. Based on data in animals and humans, the cationic amino acids lysine and arginine have been shown to enter muscle cells in exchange for potassium and lead to hyperkalemia through a shift of potassium from the intracellular to the extracellular space. Epsilon-aminocaproic acid, a synthetic amino acid structurally similar to lysine and arginine, also has been noted to cause an acute increase in serum potassium in anephric dogs infused with this medication. It is probable that the mechanism underlying the increase in serum potassium with epsilon-aminocaproic acid is also based on the shift of potassium from the intracellular to the extracellular space. Hence, it appears that intravenous epsilon-aminocaproic acid can also cause hyperkalemia in humans.