Second degree atrioventricular block Mobitz type I after administration of benzathine penicillin: case report.

BACKGROUND AND OBJECTIVES: Second degree atrioventricular block Mobitz type I is seen as a transitory change in the presence of inferior wall myocardial infarction or drug intoxication. The objective of this report was to present a case of second degree atrioventricular block Mobitz type I after administration of benzathine penicillin.

CASE REPORT: The patient had a syncopal episode and sudoresis after administration of benzathine penicillin. On physical exam, he presented diaphoresis, bradycardia, and irregular heart rate. The electrocardiogram (ECG) showed second degree atrioventricular block Mobitz type I. Intravenous atropine, 0.5 mg, was administered. An ECG done one hour later was normal. The patient remained asymptomatic and, and after six hours he was discharged.

CONCLUSIONS: The patient developed second degree atrioventricular block Mobitz type I after the administration of benzathine penicillin.