Most people have a resting heart rate between 60 and 100 beats per minute (bpm). A 15-minute brisk walk can increase heart rate to 110 to 120 bpm. Tachycardia is a heart rate above 100 bpm, and can be a side effect of clozapine. Tachycardia from clozapine is not accompanied by pain, signs of a heart attack, shortness of breath, fever, or signs of a heart rhythm problem. Those indicate a different problem and could be medical emergency. Evaluation of clozapine tachycardia excludes other causes, and can include an EKG and screening for fever, shortness of breath, smoking, caffeine, other simulants, hyperthyroidism, cardiovascular disorders, orthostatic hypotension and side effects of other medications. Early in treatment with clozapine, the possibility of myocarditis should be considered. A heart rate up to 120 beats per minute is often asymptomatic. Asymptomatic tachycardia up to 110 or 120 beats per minute can improve over time. It is typically not treated. Symptomatic tachycardia includes the medical symptoms described above, plus palpitations or anxiety. Additional evaluation, and intervention or referral, should be considered for symptomatic tachycardia or persistent tachycardia above 120 beats per minute. Interventions include reducing clozapine dosage, and reducing smoking, caffeine, stimulant medications, and stimulating supplements. Beta-blockers have been used to treat persistent tachycardia. However, beta-blockers can cause side effects, including orthostatic hypotension, and are not necessarily indicated.