Introduction: Hyperkalemia secondary to beta-adrenergic receptor blockade occurs in 1-5% of patients and is likely to develop with non-cardio-selective beta-blockers.
Case report: We have described hyperkalemia in a patient with angina pectoris receiving propranolol, clinically manifested as weakness, tightness behind the sternum and numbness in the limbs. Laboratory tests showed hyperkalemia (6.6 mmol/L), peaked T wave and a corrected QT interval of 510 ms. After discontinuation of propranolol, decline in potassium level, normalisation of electrocardiographic changes and clinical improvement were achieved. Causal relationship of drug related hyperkalemia has been confirmed as probable/likely according to Naranjo Adverse Drug Reaction Probability Score of 7 and the World Health Organization Uppsala Monitoring Centre Probability Scale.
Conclusion: Hyperkalemia can be unpredictable and life-threatening complication of propranolol or a non-selective adrenergic beta blocker treatment, and requires timely identification of cause and implementation of therapeutic measures.