Midodrine Disease Interactions

Midodrine can cause marked elevation of supine blood pressure (BP>200 mmHg systolic) and should not be used in patients with persistent and excessive supine hypertension. Systolic elevations of this degree are most likely to be observed in patients with relatively elevated pre-treatment systolic blood pressures (mean 170 mmHg). There is no experience in patients with initial supine systolic pressure above 180 mmHg, as those patients were excluded from the clinical trials. Use of midodrine in such patients is not recommended. Additionally, care should be taken when using this agent in orthostatic hypotensive patients who are also diabetic. Supine and sitting hypertension should be evaluated at the beginning of therapy, and blood pressure (supine, sitting, and orthostatic) should be monitored regularly.

The use of midodrine is contraindicated in patients with severe organic heart disease, pheochromocytoma, or thyrotoxicosis.

The use of midodrine is contraindicated in patients with acute renal disease or urinary retention/obstruction disorder. Midodrine is primarily eliminated by the kidney as desglymidodrine (active metabolite). The serum concentration of midodrine is expected to be increased in patients with renal impairment. Desglymidodrine induces urinary retention by increasing bladder neck tone. Therapy with midodrine should be administered cautiously and initiated at 2.5 mg doses in patients with compromised renal function. Clinical monitoring of renal function prior to initiation of therapy and subsequently as appropriate and blood pressure (supine, sitting, and orthostatic) is recommended. Midodrine is removed by dialysis.

Midodrine, a prodrug, undergoes bioactivation in a variety of tissues to desglymidodrine, an alpha-1 agonist. The liver functions in the metabolism of midodrine and desglymidodrine. The pharmacokinetic disposition of midodrine has not been studied in patients with hepatic impairment. Therapy with midodrine should be administered cautiously in patients with compromised hepatic function. Clinical monitoring of hepatic function prior to initiation of therapy.