Lozar

Category:

Antihypertensive , angiotensin II receptor antagonist.

Mechanism of Action:

Angiotensin II [ formed from angiotensin I in a reaction catalyzed by angiotensin converting enzyme (ACE , kininase II ) ] , is a potent vasoconstrictor , the primary vasoactive hormone of the renin - angiotensin system and an important component in the pathophysiology of hypertension. It also stimulates aldosterone secretion by the adrenal cortex. Losartan and its principal active metabolite block the vasoconstrictor and aldosterone – secreting effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor found in many tissues , (e . g ., vascular smooth muscle , adrenal gland).

Indications:

Lozar is indicated for the treatment of hypertension. It may be used alone or in combination with other antihypertensive agents. In considering the use of monotherapy with Lozar, it should be noted that in controlled trials Lozar had an effect on blood pressure that was notably less in black patients than in non-blacks , a finding similar to the small effect of angiotensin coverting enzyme inhibitors in blacks.

Contraindications:

Lozar is contraindicated in patients who are hypersensitive to any componet of this product.

Usage in pregnancy:

Pregnancy Categories C (first trimester) and D (second and third trimesters).

Nursing Mothers:

It is not known whether Lozar is excreted in human milk but significant Levels of Lozar and its avctive metabolite were shown to be present in rat milk. Because of the potential for adverse effects on the nursing infant , a decision should be made whether to discontinue nursing or discontinue the drug , taking into accountr the importance of the drug to the mother.

Pediatric Use:

Antihypertensive effects of lozar have been established in hypertensive pediatric patients aged 6 to 16 years.

Drug Interactions:

No significant drug – drug pharmacokinetic interactions have been found in interaction studies With hydrochlorothiazide, digoxin, Warfarin, cimetidine and Phenobarbital.As with other drugs that block angiotensin II or its eects , concomitant use of potassium – sparing diuretics (e.g.,spironolactone , triamterene, amiloride) , potassium supplements , or salt substitutes containing potassium may lead to increases in serum potassium.
Adverse Reactions: In general treatment with Lozar is well-tolerated. The overall incidence of adverse experiences reported with Lozar was similar to placebo. Some adverse reactions which occur in at least 1% of patients treated with Losartan and occur more frequent on Losartan than placebo are: diarrhea, muscle cramps, pain in back and leg, dizziness, nasal congestion upper respiratory infection, sinusitis

Dosage and Administration:

Initial: 50 mg once a day, Note: In patients with possible volume depletion and patients with a history of hepatic function impairment an initial dose of 25mg once a day is recommended. Maintenance: 25 to 100 mg a day. Dose may be given once a day or divided into two doses. If adequate blood pressure control is not achieved by losartan alone, a few dose of a diuretic may be added for an additive effect .
If the antigypertenseve effect measured at trough using once-a-day dosing is inadequate, a twice-a-day regimen at the same total daily dose or an increase in does may give a more satisfactory response. If blood pressure is not controlled by Lozar alone. A low does of a diuretic may be added. Hydrochlorothiazide has been shown to have an additive effect. Lozar may be administered with other antihypertensive agents, and with or without food.
Pedeiatric Hypertensive patients aged 6 to 16 years: The usual recommended starting dose is 0.7 mg/kg once daily (up to 50 mg total) administered as a tablet or a suspension.
Storage: Store below 300 C, in a tightly closed container. Protect from light.

How Supplied:

Lozar 25 & 50 mg is a available as scored, oblong film-coated tablet. There are blisters of 10'S, boxes of 30'S.

Refereces:

• USP DI 2005
• PDR 2007