Z-SAR-H (Losartan Potassium 50mg Hydrochlorothiazide 12.5mg Tablet)
Introduction
Z-Sar-H tablet is the combination of Losartan Potassium and Hydrochlorothiazide, which lowers the blood pressure effectively. Losartan is an angiotensin receptor blocker (ARB). It works by blocking the hormone angiotensin thereby relaxing blood vessels. This allows the blood to flow more smoothly and the heart to pump more efficiently. Hydrochlorothiazide is a diuretic that removes extra water and certain electrolytes from the body. Over time it also relaxes blood vessels and improves blood flow.
Indications
• congestive heart failure
• hepatic cirrhosis
• nephrotic syndrome
• chronic renal failure
• acute glomerulonephritis
• corticosteroid
Dosage : As directed by the physician
Mechanism of action
Losartan Potassium
Losartan reversibly and competitively prevents angiotensin II binding to the AT1 receptor in tissues like vascular smooth muscle and the adrenal gland. Losartan and its active metabolite bind the AT1 receptor with 1000 times more affinity than they bind to the AT2 receptor. Losartan's prevention of angiotensin II binding causes vascular smooth muscle relaxation, lowering blood pressure. Angiotensin II would otherwise bind to the AT1 receptor and induce vasoconstriction, raising blood pressure.
Hydrochlorothiazide
Hydrochlorothiazide prevents the reabsorption of sodium and water from the distal convoluted tubule, allowing for the increased elimination of water in the urine. Hydrochlorothiazide should be used with caution in patients with reduced kidney or liver function.
Pharmacology
• Losartan Potassium
Absorption
Losartan is approximately 33% orally bioavailable.
Distribution
The volume of distribution of losartan is 34.4±17.9L and 10.3±1.1L for the active metabolite (E-3174)
Excretion
A single oral dose of losartan leads to 4% recovery in the urine as unchanged losartan, 6% in the urine as the active metabolite.3,4 Oral radiolabelled losartan is 35% recovered in urine and 60% in feces. Intravenous radiolabelled losartan is 45% recovered in urine and 50% in feces.
• Hydrochlorothiazide
Absorption
An oral dose of hydrochlorothiazide is 65-75% bioavailable, when taken with a meal, bioavailability is 10% lower.
Distribution
The volume of distribution varies widely from one study to another with values of 0.83-4.19L/kg.
Excretion
Hydrochlorothiazide is eliminated in the urine as unchanged hydrochlorothiazide.
Contraindication
• Sleepiness
• Diarrhea
• Electrolyte imbalance
• Increased blood uric acid
• Glucose intolerance
• Dizziness
Precautions
• Pregnant and lactation
• Low blood pressure (hypotension) Using this drug may cause low blood pressure
• Sensitivity reaction
• Eye problems
• Allergy warning
• Alcohol interaction warning
• Warnings for people with certain health conditions