The effect on serum enzymes of intramuscular injections of digoxin, bumetanide, pentazocine and isotonic sodium chloride.

Intramuscular injections of digoxin, bumetanide, pentazocine or isotonic sodium chloride have been given to 39 patients. We followed the serum concentrations of creatine kinase (CK), aspartate aminotransferase (ASAT), lactate dehydrogenase (LDH) and LDH isoenzymes for 4 days. Ten patients receiving 500 mug digoxin showed a significant rise in CK, which lasted for 48 hours, and 6 of them had CK values exceeding the upper normal limit. Pentazocine in a dose of 30 mg given to 9 patients caused a significant rise in CK and LDH isoenzyme 1, but in no case did the level exceed the upper normal limit. No rise in ASAT or total LDH was found after digoxin and pentazocine injections. No changes in enzymes were discovered after bumetanide or isotonic sodium chloride. In the diagnostic evaluation of acute myocardial infarction, a moderate rise in CK must be assessed with caution when the patients have received i.m. injections of drugs with osmolarity and pH outside the physiological limits.