Table 1.

Options for pharmacologic treatment

Drug	Mechanism of Action	Dosing	Side Effects
Propranolol	Reduces HR by beta-adrenergic blockade	10–20 mg up to 4 times a day	Bradycardia, hypotension, fatigue, bronchospasm
Fludrocortisone	Volume expansion	0.1–0.2 mg daily	Hypokalemia, edema, headache
Desmopressin (DDAVP)	Volume expansion	0.1–0.2 mg daily	Hyponatremia, edema
Midodrine	Vasoconstriction	2.5–15 mg 3 times a day	Headache, scalp tingling, hypertension
Pyridostigmine	Cholinergic, reduces HR	30–60 mg 3 times a day	Nausea, abdominal cramps, diarrhea
Ivabradine	Reduces HR	2.5–7.5 mg twice a day	Headache, palpitations, hypertension, visual disturbance

Abbreviation: HR, heart rate.