Products
Midodrine is commercially available in the form of tablets and drops (Gutron). It has been approved in many countries since 1985.
Structure and properties
Midodrine (C12H18N2O4, Mr = 254.28 g/mol) is present in drugs as midodrine hydrochloride. Like other sympathomimetics, it has a similar structure to the catecholamines epinephrine and norepinephrine. It is a prodrug that is converted to the active metabolite desglymidodrine by cleavage of the amino acid glycine.
Effects
Midodrine (ATC C01CA17) has peripheral α-sympathomimetic properties. It constricts blood vessels, thereby increasing peripheral resistance and blood pressure. Midodrine thus improves the symptoms of hypotension. It acts exclusively peripherally because it does not cross the blood–brain barrier and has no central or cardiac effects. It may inhibit bladder emptying and lower heart rate.
Indications
Midodrine is used for orthostatic hypotension of various causes.
Contraindications
Numerous precautions must be observed during treatment. Full details can be found in the drug label.
Interactions
Interactions are possible with the following agents, among others: alpha blockers, beta blockers, cardiac glycosides, atropine, glucocorticoids, vasoconstrictors, sympathomimetics, tricyclic antidepressants, antihistamines, thyroid hormones, MAO inhibitors, alcohol.
Adverse effects
Adverse effects can be attributed to the sympathomimetic effects. The most common possible complaints include increased blood pressure while lying down, formication, sensory disturbances, itching, skin redness, chills, and goose bumps.
