Pyridostigmine induced symptomatic bradycardia in a patient with atonic bladder

Drug induced bradycardia is a frequent reason for hospitalization in cardiology clinic. Knowing the causes of this type of bradycardia is important for the proper management of these patients. Pyridostigmine bromide is an indirect parasympathomimetic drug, inhibitor of the cholinesterase enzyme. Pyridostigmine decrease the breakdown of acetylcholine, which is the natural neurotransmitter of the electrical impulses send by the somatic and parasympathetic nervous systems. Despite its relative safety and effectiveness, in rare cases there have been reports of conduction disturbances of the heart. In this clinical case report, we present a patient with atonic bladder treated with pyridostigmine. The patient developed a rare adverse reaction of the drug with an induced second-degree аtrioventricular block 2:1 type. The bradycardia caused pronounced symptoms which forced hospitalization in intensive cardiology clinic.