Serum creatine phosphokinase elevation in patients treated with intravenous magnesium sulfate.

ABSTRACT

OBJECTIVE: During the treatment of pre-term labor with magnesium sulfate, we noted an abnormal elevation of maternal serum creatine phosphokinase. This study was aimed at evaluating the relationship between tocolysis with MgSO4 and maternal serum CPK elevation, which represents the possible damage of muscles by magnesium sulfate. METHODS: Clinical records of 45 women treated with magnesium sulfate and beta-sympathomimetics for the treatment of pre-term labor were retrospectively examined. RESULTS: Serum CPK was abnormally elevated in 32 out of 45 cases (71.1%), but in only one out of 21 in the control group. In three cases, the decrease of serum creatine phosphokinase after cessation of magnesium sulfate was demonstrated, despite the continuous infusion of beta-sympathomimetics. CONCLUSION: Magnesium sulfate may cause muscular damage and abnormal elevation of maternal serum creatine phosphokinase. Special attention must be paid to patients when drugs acting on muscle cells, for example succinyl choline, are going to be used.