Midodrine is classified as a sympathomimetic amine [1]. It is specifically a prodrug that is converted to its active form, desglymidodrine, which acts as an alpha-1 adrenergic agonist [2].
What does midodrine do in the body?
Desglymidodrine causes vasoconstriction, meaning it narrows blood vessels [2]. This action increases peripheral vascular resistance, which in turn elevates blood pressure [2]. This effect is particularly useful in treating symptomatic orthostatic hypotension, a condition where blood pressure drops significantly upon standing [3].
How long does midodrine take to work?
The onset of action for midodrine occurs approximately 30 minutes after oral administration, with peak plasma concentrations reached around 2 hours post-dose [2]. The duration of its effect on blood pressure typically lasts for about 3 to 4 hours [2].
What are the side effects of midodrine?
Common side effects associated with midodrine include supine hypertension (elevated blood pressure while lying down), paresthesia (tingling or prickling sensation), pruritus (itching), and urinary urge or retention [4]. Less common side effects can involve dizziness, headache, and flushing [4].
How is midodrine prescribed?
Midodrine is typically administered orally three times a day. Dosing should be carefully adjusted to achieve the desired blood pressure response while minimizing side effects, particularly supine hypertension [3][4]. It is often advised to take the last dose several hours before bedtime to avoid nocturnal hypertension [3].
Are there alternatives to midodrine for orthostatic hypotension?
Other treatment options for orthostatic hypotension may include lifestyle modifications like increasing salt and fluid intake, and wearing compression stockings [3]. Pharmacological alternatives can include fludrocortisone and droxidopa [3]. The choice of treatment depends on the underlying cause and specific patient profile.