Medication Summary

The goals of pharmacotherapy are to reduce morbidity and prevent complications.

Class Summary

These agents improve the hemodynamic status by increasing myocardial contractility and heart rate, resulting in increased cardiac output. They also increase peripheral resistance by causing vasoconstriction. Increased cardiac output and increased peripheral resistance lead to increased blood pressure.

Droxidopa (Northera)

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Droxidopa is a synthetic amino acid analog directly metabolized to norepinephrine by dopadecarboxylase. Increases blood pressure by inducing peripheral arterial and venous constriction.

Class Summary

These agents have anti-inflammatory properties and cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli.

Fludrocortisone

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Fludrocortisone may increase blood volume by promoting salt and water retention.

Class Summary

These agents are hormones that stimulate the production of red cells from the erythroid tissues in the bone marrow.

Epoetin alfa (Procrit, Epogen)

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Purified glycoprotein produced from mammalian cells modified with gene coding for human erythropoietin (EPO). Amino acid sequence is identical to that of endogenous EPO. Biological activity mimics human urinary EPO, which stimulates division and differentiation of committed erythroid progenitor cells and induces release of reticulocytes from bone marrow into the blood stream. By increasing red blood cell mass it may increase blood volume.

Class Summary

These agents raise the concentration of acetylcholine, by inhibiting the degradation of Ach, at the myoneural junction and increase the chance of activating the acetylcholine receptor.

Pyridostigmine bromide (Mestinon)

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Pyridostigmine bromide acts in smooth muscle, CNS, and secretory glands where it blocks the action of ACh at parasympathetic sites. It may enhance autonomic activity.

Class Summary

These drugs are used to treat orthostatic hypotension that is refractory to nonpharmacologic recommendations.

Midodrine

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Midodrine is a selective alpha1-adrenergic agonist used for the treatment of hypotension.

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Media Gallery

Decreased CBFv measured by transcranial Doppler ultrasound occurs during a VVS (upper panel), and in postural tachycardia syndrome (POTS) (lower panel). During VVS, CBF declines gradually at first and then more abruptly as the patient acutely loses consciousness. In POTS, CBF is fairly uniformly reduced; there is no loss of consciousness although lightheadedness is typical.
Neurogenic Orthostatic Hypotension. Arterial blood pressure (upper panel) declines steadily during upright stance, while heart rate (lower panel) is only slightly increased.
Diagram showing representative heart rate (upper panel) and mean arterial pressure (MAP -lower panel) during upright tilt in a postural tachycardia syndrome patient (POTS). Heart rate increases, while MAP is stable throughout tilt in POTS.
Immediate Orthostatic Hypotension (IOH) upon standing. There is a short-lived decrease in blood pressure (BP - upper panel) and increase in heart rate (HR - lower panel). The fall in BP is resolved within 20 seconds. The patient experienced transient lightheadedness.
Heart rate (upper panel) and mean arterial pressure (MAP - lower panel) during upright tilt in a representative postural syncope patient. Changes during tilt occur over three stages: during the first stage (1), following initial hypotension, MAP stabilizes slightly higher than resting pressure while heart rate increases. During the second stage (2), MAP begins to fall gradually, while heart rate continues to increase. Note that the increment in heart rate from supine to upright fulfills tachycardia criteria for postural tachycardia syndrome (POTS). During the third stage (3), MAP and then heart rate fall abruptly and rapidly as loss of consciousness supervenes.
Hemodynamic and neurovascular changes during upright tilt in a representative healthy volunteer. The left panel shows from top to bottom: arterial pressure, muscle sympathetic nerve activity (MSNA) from the peroneal nerve, heart rate (HR) and cardiac output. The right panel shows from top to bottom: total peripheral resistance (TPR), cerebral blood flow velocity (CBFv) by transcranial Doppler ultrasound, stroke volume and a vagal index calculated from the respiratory sinus arrhythmia component of the frequency spectrum of HR variability. During upright tilt at 275 seconds (s), systolic, diastolic and arterial pressures increase slightly, while pulse pressure is decreased with a decrease in stroke volume by approximately 40%. HR increases so that cardiac output is only decreased by 20% because of the increase in HR. CBFv decreases by 5-10%. Both total peripheral vascular resistance and muscle sympathetic nerve activity increase, while the vagal index decreases, reflecting, respectively, sympathetic activation and parasympathetic withdrawal.
An asystolic faint. Electrocardiogram (upper panel) and blood pressure (BP) (lower panel) in a patient who experienced an asystole during faint. This is episodic, relatively infrequent, and unrelated to intrinsic sinus node disease. Asystolic faints are associated with opisthotonic posturing and have been sometimes referred to as convulsive syncope.

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Orthostatic Intolerance Medication

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Alpha/Beta Agonists