Editing Sinus node dysfunction (section)

=== Extrinsic causes ===
Common cardiac pharmacology such as [[Beta blocker|beta-blockers]], [[calcium channel blocker]]s, [[digoxin]], sympatholytic medication, and other antiarrhythmics can alter sinus node function to create an arrhythmia such as sick sinus syndrome. Electrolyte abnormalities such as [[hyperkalemia]], [[hypokalemia]], and [[Hypocalcaemia|hypocalcemia]] can also alter normal sinus node functioning. [[Hypothyroidism]], [[Hypoxia (medical)|hypoxia]], [[hypothermia]], and various toxins have also been associated with sinus node dysfunctions.<ref name="Semelka20132" /><ref name="John2016" />