Table 3.

Short acting pressor agents used in the management of orthostatic hypotension

Agent	Mechanism of action	Dosing	Side effects	Comments
Midodrine	Alpha-1 adrenoreceptor agonist Increases peripheral vascular resistance	2.5–10 mg Up to three times/daytime	Scalp tingling (piloerection) Supine hypertension Urinary retention Avoid in heart failure (increases afterload)	Can be used as needed prior to upright activity [LE:1b]
Droxidopa	Prodrug, metabolized to norepinephrine by dopa-decarboxylase	100–600 mg Three times/daytime Rapid titration possible in hospital 42	Supine hypertension Headache Nausea	Ideally obtain baseline catecholamines before initiating this treatment More effective in patients with low plasma norepinephrine 30 Preferred over midodrine in heart failure patients 10 [LE:1b]
Pyridostigmine	Acetylcholinesterase inhibitor Enhances cholinergic transmission in autonomic ganglia	30–60 mg Two three times/daytime	GI disturbances (cramps, nausea, diarrhea)	More effective in patients with mild orthostatic hypotension cases and residual sympathetic reserve Less effective in severe cases, but synergistic pressor effect when given with atomoxetine 43 [LE:2b]
Atomoxetine	Norepinehrine reuptake inhibitor	10–40 mg (18 mg most often used) Twice/daytime	Headache Insomnia Nausea Supine hypertension (less than midodrine) Mood swings Tachycardia	Should not be used in patients with QT prolongation because of the risk of arrhythmias 44, 45 Potentiates endogenous released norepinephrine; more effective in patients with residual sympathetic reserve [LE:2b]

[LE], Level of Evidence