Irbesartan

Irbesartan (中文:厄貝沙坦) is an angiotensin receptor blocker. 

Pronunciation

Irbesartan 150mg (APROVEL 150mg)

Generic Name:	Irbesartan
Class:	Cardiovascular Drug
Subclass:	angiotensin receptor blocker
Legal Classification:	P1S1S3

Drug Names

Generic Name 藥物化學名稱	HA Code 藥物代碼	Legal Classification法律藥物分類	Brand Name 藥名
Irbesartan Tablet 150mg	IRBE01	P1S1S3	APROVEL TABLET C0APROVEL TAB 150/12.5MG (irbesartan 150mg + hydrochlorothiazide 12.5mg) C0APROVEL TAB 300/12.5MG (irbesartan 300mg + hydrochlorothiazide 12.5mg)
Irbesartan Tablet 300mg	IRBE02	P1S1S3

Mechanism of Action

Irbesartan relaxes and widens your blood vessels. This lowers your blood pressure and makes it easier for your heart to pump blood around your body. It is used to treat high blood pressure and heart failure. It helps to prevent future strokes, heart attacks and diabetic kidney disease. If you have diabetic kidney disease, it helps to protect your kidneys and slows down the disease. It reduces high blood pressure and the amount of protein you lose through your kidneys.

Route of Administration

Irbesartan is given orally as tablets. After a dose the hypotensive effect peaks within 3 to 6 hours and persists for at least 24 hours. The maximum hypotensive effect is achieved within 4 to 6 weeks after starting therapy.

Dosage

The dose of irbesartan depends on why you need the medicine.

The usual dose for both high blood pressure and diabetic kidney disease is 150mg to 300mg, taken once a day.

If you are over 75, or you have liver or kidney problems, your dose may be lower. Initially 75mg – 150mg once a day.

Side Effects

The following definitions of frequencies are used:

Very common ≥ 1/10

Common ≥ 1/100 to < 1/10

Uncommon ≥ 1/1,000 to < 1/100

Rare ≥ 1/10,000 to < 1/1,000

Very rare < 1/10,000

System Organ Class	Frequency	Adverse reactions
Nervous system disorders	Very rare	Dizziness, fatigue
Respiratory disorders	Very rare	Very rare cough
Musculoskeletal disorders	common	Musculoskeletal pain
Gastro-intestinal disorders	Common	Nausea, vomiting
Vascular disorder	Common	Hypotension
Metabolism disorders	common	Hyperkalaemia
	Very rare	hyponatraemia

Pharmacokinetics

Peak plasma concentrations of irbesartan occur 1.5 to 2 hours after an oral dose.

Irbesartan is about 96% bound to plasma proteins.

It undergoes some metabolism in the liver, primarily by the cytochrome P450 isoenzyme CYP2C9, to inactive metabolites. It is excreted as unchanged drug and metabolites in the bile and in urine. The terminal elimination half-life is about 11 to 15 hours.

PREGNANCY should be avoided in pregnancy unless essential.

BREAST FEEDING They are not recommended.

MONITORING REQUIREMENTS

Monitor plasma-potassium concentration, particularly in the elderly and in patients with renal impairment.

Drug Interaction:

Diuretics: enhanced hypotensive effect when given with diuretics

Potassium sparing diuretics (triamterene, amiloride and spironolactone) or potassium supplement: increase risk of hyperkalaemia

Caution:

• Aortic or mitral valve stenosis
• Hypertrophic cardiomyopathy
• Patients with a history of angioedema
• Patients with primary aldosteronism

Contraindication:

The concomitant use of irbesartan with aliskiren-containing products is contraindicated in patients with diabetes mellitus or renal impairment (if eGFR < 60ml/minute/1.73m2)