Midodrine Pharmacology Podcast

Midodrine is an oral alpha-1 agonist most commonly used for the treatment of symptomatic orthostatic hypotension. Its mechanism of action is through peripheral vasoconstriction, which helps increase blood pressure. Because of its short duration of action, it is typically dosed three times daily, with the last dose recommended in the late afternoon to reduce the risk of hypertension at night. Clinically, midodrine is often considered when non-pharmacologic strategies for orthostatic hypotension (such as increased salt/fluid intake, compression stockings, or physical counter-maneuvers) are not enough. Pharmacists should also be aware of prescribing cascades—such as urinary retention leading to tamsulosin initiation—that can arise when midodrine is used. Midodrine is generally not metabolized through cytochrome P450 pathways, so significant drug–drug interactions are less common. However, caution should be exercised with other agents that can raise blood pressure (like decongestants) or slow the heart rate (such as beta-blockers). Monitoring parameters include blood pressure, pulse, symptoms of urinary retention, and the patient’s overall response to therapy.