For refractory symptomatic cases, isoproterenol, epinephrine, dopamine, and pacing can be considered.[4,12] It is prudent to weigh these risk factors when considering initiating or increasing clonidine therapy, or when using other centrally acting alpha-2 receptor agonists, such as guanabenz and guanfacine, which may cause the same effect.[21,22] This should include taking a thorough cardiac and medication history and possibly obtaining renal function tests and an ECFG
if the history indicates potential problems. When following a patient on clonidine, the patient's pulse rate and blood pressure should be checked. Clonidine should be used with caution in a patient with known sinus node dysfunction, and patients with renal impairment should be considered for reduced dosages.