Midodrine is a prodrug which forms an active metabolite, desglymidodrine, which is an α1-receptor agonist and exerts its actions via activation of the alpha-adrenergic receptors of the arteriolar and venous vasculature, producing an increase in vascular tone and elevation of blood pressure.
After oral administration, midodrine is rapidly absorbed. The plasma levels of the prodrug peak after about half an hour, and decline with a half-life of approximately 25 minutes, while the metabolite reaches peak blood concentrations about 1 to 2 hours after a dose of midodrine and has a half-life of about 3 to 4 hours.
It can reduce dizziness and faints by about a third, but can be limited by troublesome goose bumps. Small studies have also shown that midodrine can be used to prevent excessive drops in blood pressure in people requiring dialysis.
Midodrine is contraindicated in patients with severe organic heart disease, acute renal disease, urinary retention, pheochromocytoma or thyrotoxicosis. Midodrine should not be used in patients with persistent and excessive supine hypertension.
Headache; feeling of pressure/fullness in the head, vasodilation/flushing face, confusion/thinking abnormality, dry mouth; nervousness/anxiety and rash