Milfasartan

Milfasartan

Milfasartan is a pharmaceutical compound classified as an angiotensin II receptor blocker (ARB), primarily used in the management of hypertension and certain types of heart failure. It functions by inhibiting the effects of angiotensin II, a potent vasoconstrictor, thereby promoting vasodilation and reducing blood pressure.

Pharmacology

Milfasartan selectively blocks the binding of angiotensin II to the AT1 receptor, which is found in various tissues such as vascular smooth muscle and the adrenal gland. By preventing this interaction, milfasartan reduces vasoconstriction, aldosterone secretion, and sodium reabsorption, leading to decreased blood pressure and reduced cardiac workload.

Mechanism of Action

Angiotensin II is a key component of the renin-angiotensin-aldosterone system (RAAS), which regulates blood pressure and fluid balance. Milfasartan's mechanism of action involves competitive antagonism at the AT1 receptor, thereby:

• Inhibiting vasoconstriction
• Reducing aldosterone release
• Decreasing sodium and water retention

Pharmacokinetics

Milfasartan is administered orally and is well absorbed from the gastrointestinal tract. It undergoes hepatic metabolism, primarily via the cytochrome P450 enzyme system, and is excreted in both urine and feces. The drug has a half-life of approximately 6-9 hours, allowing for once-daily dosing in most patients.

Clinical Uses

Milfasartan is indicated for:

• Hypertension: As a first-line treatment or in combination with other antihypertensive agents.
• Heart Failure: To improve symptoms and reduce the risk of hospitalization in patients with heart failure with reduced ejection fraction (HFrEF).
• Diabetic Nephropathy: To slow the progression of kidney disease in patients with type 2 diabetes and hypertension.

Adverse Effects

Common side effects of milfasartan include:

• Dizziness
• Hyperkalemia
• Fatigue
• Renal impairment

Rare but serious adverse effects may include:

• Angioedema
• Severe hypotension

Contraindications

Milfasartan is contraindicated in patients with:

• Hypersensitivity to the drug or its components
• Pregnancy, due to the risk of fetal toxicity
• Severe renal impairment without close monitoring

Drug Interactions

Milfasartan may interact with:

• Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): May reduce the antihypertensive effect and increase the risk of renal impairment.
• Potassium-sparing diuretics: May increase the risk of hyperkalemia.
• Lithium: May increase serum lithium levels and risk of toxicity.

Also see

• Angiotensin II receptor blocker
• Renin-angiotensin-aldosterone system
• Hypertension management
• Heart failure treatment

{{Drugbox | Verifiedfields = changed | verifiedrevid = 477002123 | IUPAC_name = (2-butyl-4-chloro-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-imidazol-5-yl)methanol | image = Milfasartan_structure.png | width = 250 | tradename = Milfartan | pregnancy_AU = D | pregnancy_US = D | legal_AU = S4 | legal_US = Rx-only | routes_of_administration = Oral | bioavailability = 60% | protein_bound = 99% | metabolism = Hepatic | elimination_half-life = 6–9 hours | excretion = Urine (35%), feces (65%) }}