midodrine hydrochloride: clinical use

Prescribing considerations

• Confirm severe orthostatic hypotension due to autonomic dysfunction and address reversible factors before prescribing.
• Assess ongoing symptomatic benefit against risks, particularly supine hypertension; long-term evidence is limited.
• Use caution in atherosclerotic disease, prostate disorders, hepatic impairment and with medicines that reduce heart rate.
• Be aware that midodrine may interfere with some HILIC-based HPLC-MS/MS plasma metanephrine assays.

Contraindications and cautions

• Hypertension or clinically important supine hypertension
• Severe organic heart disease, including relevant bradycardia, conduction disease, heart failure, previous myocardial infarction or aortic aneurysm
• Serious occlusive vascular disease, cerebrovascular occlusion or vasospasm
• Acute kidney disease or severe renal impairment
• Serious prostate disorder or urinary retention
• Proliferative diabetic retinopathy
• Phaeochromocytoma
• Hyperthyroidism
• Narrow-angle glaucoma
• Hypersensitivity to the active substance or an excipient

Monitoring

• Supine and standing blood pressure before and during treatment
• Renal and hepatic parameters before treatment and periodically
• Heart rate and symptoms of bradycardia
• Urinary symptoms, particularly in patients with prostate disease
• Symptoms of excessive supine blood pressure, including chest pain, palpitations, dyspnoea, headache and blurred vision
• Intraocular pressure when combined with mineralocorticoids or glucocorticoids where clinically relevant

Clinical pharmacology

Midodrine is a rapidly absorbed prodrug converted in the intestine and plasma to desglymidodrine. The active metabolite selectively stimulates peripheral alpha-1 receptors, increasing venous tone and peripheral arterial resistance; elimination is predominantly renal.

Formulation and product differences

• The selected product is an oral tablet.
• Its score line facilitates breaking for swallowing but does not provide equal portions.
• Excipients and whether score lines provide equal portions can differ between manufacturers; check the product-specific SmPC.

Tablet

Route: Oral

Strengths: 2.5 mg, 5 mg, 10 mg