Midodrine 💊

📖 About Midodrine

• Always check the BNF entry here for current prescribing advice.
• Vasopressor used for orthostatic (postural) hypotension and autonomic dysfunction.
• Active metabolite = desglymidodrine.

⚙️ Mode of Action

• Peripheral α-adrenergic receptor agonist.
• Causes arteriolar and venous vasoconstriction → ↑ vascular tone → ↑ BP.

🎯 Indication & Dosing

• Indication: Symptomatic orthostatic hypotension.
• Start: 2.5 mg three times daily (TDS).
• Maintenance: usually 10 mg TDS (max 30 mg/day).
• ⚠️ Avoid evening dosing → last dose ≥ 4 hrs before bedtime (reduces risk of supine hypertension).

🔀 Interactions

• See BNF for complete list.
• Potential interactions with sympathomimetics, digoxin, and corticosteroids.

⚠️ Cautions

• Use with care in: atherosclerosis, elderly, prostate disease, renal impairment.
• Monitor BP lying & standing → risk of hypertension.

🚫 Contraindications

• Severe organic heart disease.
• Hypertension (including supine hypertension).
• Urinary retention or severe prostate disease.
• Phaeochromocytoma or thyrotoxicosis.
• See BNF for full list.

💥 Side Effects

• Pilomotor reactions (goosebumps), pruritus, paraesthesia.
• Urinary retention, dysuria.
• Supine hypertension (most important to monitor).
• Headache, chills, GI upset.

📚 References

• BNF – Midodrine
• European Society of Cardiology: management of autonomic dysfunction.