Desglymidodrine

Desglymidodrine

Desglymidodrine is a pharmacologically active metabolite of the prodrug midodrine, which is used primarily in the treatment of orthostatic hypotension. It is an alpha-1 adrenergic receptor agonist that causes vasoconstriction, thereby increasing blood pressure.

Pharmacology

Desglymidodrine is the active form of midodrine, which is converted in the liver. Once administered, midodrine is rapidly absorbed and undergoes enzymatic hydrolysis to form desglymidodrine. This conversion is crucial for its therapeutic effects, as desglymidodrine is responsible for the vasopressor activity.

Mechanism of Action

Desglymidodrine acts by stimulating alpha-1 adrenergic receptors located on the smooth muscle cells of blood vessels. This stimulation leads to vasoconstriction, which increases peripheral vascular resistance and subsequently elevates blood pressure. This mechanism is particularly beneficial in patients with orthostatic hypotension, where blood pressure drops significantly upon standing.

Clinical Use

Desglymidodrine, through its prodrug midodrine, is indicated for the treatment of symptomatic orthostatic hypotension. It helps in reducing symptoms such as dizziness, lightheadedness, and fainting by maintaining adequate blood pressure levels when a person stands up.

Pharmacokinetics

After oral administration of midodrine, it is rapidly absorbed and converted to desglymidodrine. The peak plasma concentration of desglymidodrine is typically reached within 1 to 2 hours. The elimination half-life of desglymidodrine is approximately 3 to 4 hours, which necessitates multiple dosing throughout the day to maintain its therapeutic effect.

Side Effects

Common side effects associated with desglymidodrine include:

• Supine hypertension
• Piloerection (goosebumps)
• Pruritus (itching)
• Urinary retention

Patients are advised to monitor their blood pressure regularly and report any significant increases, especially when lying down, as this can lead to supine hypertension.

Contraindications

Desglymidodrine is contraindicated in patients with:

• Severe organic heart disease
• Acute renal disease
• Urinary retention
• Pheochromocytoma

See Also

• Midodrine
• Orthostatic hypotension
• Alpha-1 adrenergic receptor

References

• Smith, M. C., & Porth, C. M. (2008). Pathophysiology: Concepts of Altered Health States. Lippincott Williams & Wilkins.
• Freeman, R. (2008). Clinical Autonomic Disorders: Evaluation and Management. Springer.