Osartil25 mg

Hypertension

Osartil is established (FDA-approved) for the treatment of hypertension, alone or in combination with other antihypertensive agents, in adults and in children 6 years of age and older, to lower blood pressure.

Diabetic Nephropathy

Osartil is established for the treatment of diabetic nephropathy in patients with type 2 diabetes and hypertension, with an elevated serum creatinine and proteinuria (urinary albumin-to-creatinine ratio ≥300 mg/g), or with a history of both type 2 diabetes and hypertension. In this population, Osartil reduces the rate of progression of nephropathy, as measured by the occurrence of doubling of serum creatinine or end-stage renal disease (need for dialysis or renal transplantation).

Stroke Risk Reduction in Hypertension with Left Ventricular Hypertrophy

Osartil is established for reducing the risk of stroke in patients with hypertension and electrocardiographically documented left ventricular hypertrophy (LVH). Of note, this benefit was not seen in Black patients in the pivotal trial, so alternative agents may be preferred for stroke-risk reduction in this population; Osartil still lowers blood pressure effectively in Black patients.

Each tablet contains Losartan Potassium as the active ingredient. In Bangladesh, Losartan Potassium is available as 25 mg, 50 mg, and 100 mg film-coated tablets, and is also marketed in fixed-dose combination products with hydrochlorothiazide.

Osartil is an angiotensin II receptor blocker (ARB) used mainly to treat high blood pressure (hypertension) and to protect the kidneys in people with type 2 diabetes who have diabetic kidney disease. It works by blocking the action of angiotensin II, a hormone that normally causes blood vessels to narrow, so blood vessels relax and blood pressure falls. Osartil is also used to reduce the risk of stroke in certain hypertensive patients with an enlarged heart (left ventricular hypertrophy). It is generally well tolerated and, unlike ACE inhibitors, is much less likely to cause a persistent dry cough.

Angiotensin II Receptor Blocker (ARB)

Losartan Potassium is well absorbed after oral administration and undergoes substantial first-pass metabolism, being converted in part by the liver (mainly CYP2C9 and CYP3A4) to an active carboxylic acid metabolite (E-3174), which is 10-40 times more potent than Losartan Potassium itself as an angiotensin II receptor antagonist and accounts for most of the angiotensin II receptor blockade. Peak plasma concentrations of Losartan Potassium occur about 1 hour after dosing, and of its active metabolite about 3-4 hours after dosing. The elimination half-life of Losartan Potassium is about 2 hours and of the active metabolite about 6-9 hours, but the antihypertensive effect is maintained over 24 hours, allowing once-daily dosing. Losartan Potassium and its active metabolite are excreted in both urine and bile/feces.

• Take Osartil once daily at approximately the same time each day, with or without food.
• Swallow the tablet whole with a glass of water.
• Continue taking Osartil even if you feel well; hypertension often has no symptoms, and Osartil works best when taken consistently.
• Do not stop taking Osartil without consulting your doctor.
• If a dose is missed, take it as soon as remembered unless it is almost time for the next dose; do not double the dose to make up for a missed one.

• Potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium: concurrent use with Osartil can lead to significant hyperkalemia; combined use requires caution and monitoring of serum potassium (see Precautions and Warnings).
• ACE inhibitors or aliskiren (dual renin-angiotensin system blockade): combining Osartil with these agents increases the risk of hyperkalemia, hypotension, and changes in renal function compared with either agent alone; dual blockade is generally not recommended, and concurrent use of Osartil with aliskiren is contraindicated in patients with diabetes (see Contraindications).
• NSAIDs (including selective COX-2 inhibitors): may reduce the antihypertensive effect of Osartil and, particularly in elderly, volume-depleted, or renally impaired patients, may increase the risk of acute kidney injury; renal function should be monitored when these are used together.
• Lithium: Osartil and other agents acting on the renin-angiotensin system can reduce lithium clearance and increase serum lithium levels, raising the risk of lithium toxicity; lithium levels should be monitored closely if co-administered.
• Rifampin and fluconazole: these drugs reduce the formation of the active metabolite of Osartil, which may reduce its antihypertensive effect; blood pressure should be monitored if used together.
• Other antihypertensive agents and drugs that lower blood pressure: combined use with Osartil has an additive blood-pressure-lowering effect, which is often intentional in combination therapy but increases the risk of symptomatic hypotension.

Common Side Effects

• Dizziness
• Upper respiratory tract infection symptoms and nasal congestion
• Back pain and muscle cramps
• Fatigue
• Diarrhea
• Mild to moderate increases in blood potassium (hyperkalemia)

Less Common or Serious Side Effects (Seek Medical Attention)

• Symptomatic low blood pressure: severe dizziness, lightheadedness, or fainting, especially after the first dose or in volume-depleted patients (see Precautions and Warnings)
• Signs of significant hyperkalemia: muscle weakness, irregular heartbeat, or tingling sensations (see Precautions and Warnings)
• Signs of worsening kidney function: decreased urination, swelling, or unusual fatigue, particularly in patients with renal artery stenosis or pre-existing kidney disease
• Signs of an allergic/anaphylactoid reaction or angioedema: swelling of the face, lips, tongue, or throat, and difficulty breathing or swallowing (rare, but requires immediate medical attention)
• Signs of liver problems: yellowing of the skin or eyes, dark urine, or unusual tiredness

Pregnancy

Osartil is contraindicated in pregnancy. Drugs that act directly on the renin-angiotensin system, including Osartil, can cause injury or death to the developing fetus when used during the second and third trimesters, including fetal renal failure, oligohydramnios, hypoplastic fetal lung development, skeletal deformations, and hypotension. When pregnancy is detected, Osartil should be discontinued as soon as possible, and an alternative antihypertensive agent should be used under a physician's guidance, since hypertension in pregnancy itself carries maternal and fetal risk.

Breastfeeding

It is not known whether Osartil passes into human breast milk in significant amounts. Because of the potential for serious adverse effects in a nursing infant, a decision should be made, in consultation with a physician, whether to discontinue breastfeeding or discontinue Osartil, taking into account the importance of the medicine to the mother; an alternative antihypertensive with a better-established breastfeeding safety profile is often preferred while nursing.

• Fetal toxicity: Osartil must be discontinued as soon as pregnancy is detected because of the risk of fetal injury or death (see Pregnancy and Lactation).
• Hypotension in volume- or salt-depleted patients: symptomatic hypotension may occur after the first dose in patients who are volume- or salt-depleted (e.g., from diuretic therapy, dietary salt restriction, dialysis, diarrhea, or vomiting); this should be corrected before starting Osartil, or Osartil should be started at a lower dose (25 mg once daily) under medical supervision.
• Hyperkalemia: Osartil can raise serum potassium, particularly in patients with renal impairment, diabetes, or those taking potassium supplements, potassium-sparing diuretics, or salt substitutes containing potassium; periodic monitoring of serum potassium is advised in at-risk patients (see Interaction).
• Impaired renal function: as with other drugs that inhibit the renin-angiotensin system, changes in renal function, including acute renal failure, can occur in patients whose renal function depends on the activity of this system (e.g., severe heart failure or bilateral renal artery stenosis, or stenosis in a single functioning kidney); Osartil should be used with caution in these patients, with monitoring of renal function.
• Anaphylactoid reactions and angioedema: rare cases of angioedema involving the face, lips, tongue, and/or throat have been reported; the risk is lower than with ACE inhibitors but not absent; if angioedema occurs, Osartil should be discontinued immediately and emergency care sought.
• Hepatic impairment: plasma concentrations of Osartil are significantly increased in patients with hepatic cirrhosis; a lower starting dose should be considered (see Dosage).

The most likely manifestations of Osartil overdose are hypotension and tachycardia; bradycardia could also occur from excessive vagal (parasympathetic) stimulation. If an overdose of Osartil is suspected, seek immediate medical attention or contact a poison control center right away; do not attempt home treatment. Management is supportive: maintenance of adequate fluid intake, and treatment of symptomatic hypotension with appropriate supportive measures under medical supervision. Osartil and its active metabolite are not removed by hemodialysis.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

• Children: the antihypertensive effect of Osartil has been studied in patients 6 to 16 years of age; it is not recommended in children under 6 years of age or in pediatric patients with glomerular filtration rate below 30 mL/min/1.73m², since it has not been studied in these groups (see Pediatric Uses).
• Elderly patients: no overall differences in effectiveness were observed between elderly and younger patients; dose adjustment based on age alone is generally not required, but elderly patients are more prone to volume depletion and hypotension.
• Hepatic impairment: Osartil exposure is significantly increased in patients with hepatic cirrhosis; a lower starting dose should be considered, with close monitoring (see Precautions and Warnings).
• Renal impairment: no initial dosage adjustment is generally necessary in mild-to-moderate renal impairment, but Osartil should be used cautiously with monitoring of renal function and serum potassium, particularly in patients with renal artery stenosis; Osartil is not removed by hemodialysis.
• Pregnant and breastfeeding women: see Pregnancy and Lactation for detailed guidance; Osartil is contraindicated in pregnancy.

Osartil is typically used long-term for the ongoing control of hypertension and for slowing the progression of diabetic kidney disease, since these are chronic conditions requiring continuous management rather than short-term treatment. The duration of therapy is determined by the prescribing physician based on blood pressure control, kidney function, and tolerability, with periodic follow-up to reassess the continued need for and dose of Osartil. Osartil should not be stopped without medical advice, except immediately upon detection of pregnancy.

Angiotensin II Receptor Blocker (ARB) - Biphenyl tetrazole derivative

Losartan Potassium and its active metabolite selectively block the binding of angiotensin II to the AT1 receptor found in vascular smooth muscle and the adrenal gland, without affecting the AT2 receptor or other hormone receptors or ion channels important for cardiovascular regulation. By blocking the AT1 receptor, Losartan Potassium prevents the vasoconstrictor and aldosterone-secreting effects of angiotensin II, resulting in vasodilation, reduced peripheral vascular resistance, and a decrease in aldosterone-mediated sodium and water retention, which together lower blood pressure. Because Losartan Potassium blocks the receptor rather than the angiotensin-converting enzyme, it does not affect bradykinin breakdown, which explains its much lower incidence of dry cough compared with ACE inhibitors.

D

Osartil's antihypertensive effect has been established in pediatric patients 6 to 16 years of age, based on studies in this age group; the typical initial dose is approximately 0.7 mg/kg once daily up to a maximum of 50 mg, adjusted according to blood pressure response, and doses above 1.4 mg/kg (or above 100 mg) daily have not been studied in children. Osartil is not recommended in children under 6 years of age or in pediatric patients with a glomerular filtration rate below 30 mL/min/1.73m², because it has not been studied in these populations. Safety and efficacy of Osartil for diabetic nephropathy or stroke risk reduction have not been established in pediatric patients.