Generic: Losartan Potassium Hydrochlorothiazide  |  Dosage Form: Tablet  |  Manufacturer: Novatek Pharmaceuticals Ltd.

Indications

This combination tablet is indicated for the treatment of hypertension. It is also indicated to reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy.

Dosage & Administration

Hypertension-

• The usual starting dose of this combination 50/12.5 is one tablet once daily.
• For patients who do not respond adequately to one tablet the dosage may be increased to 100/25 once daily.
• A patient whose blood pressure is not adequately controlled with Losartan 100 mg monotherapy may be switched to this combination 100/12.5 once daily.
• In hypertensive patients with left ventricular hypertrophy initial dose is 50/12.5, if additional blood pressure reduction is needed, 100/12.5 may be given, followed by 100/25 if required. The maximum dose is 100/25 once daily.
• In general, the antihypertensive effect is attained within three weeks after initiation of therapy.
• No initial dosage adjustment of 50/12.5 is necessary for elderly patients. But maximum dose of 100/25 once daily dose should not be used as initial therapy in elderly patients.

Severe Hypertension:

• The starting dose for initial treatment of severe hypertension is one tablet of 50/12.5 once daily.
• For patients who do not respond adequately to this dose after 2 to 4 weeks of therapy, the dosage may be increased to 100/25 once daily. The maximum dose is one tablet of 100/25 once daily.

Interaction

Losartan Potassium: 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 effects, concomitant use of potassium-sparing diuretics (e.g. Spironolactone, Triamterene, Amiloride), potassium supplements, or salt substitutes containing potassium may lead to increase in serum potassium. As with other antihypertensive agents, the antihypertensive effect of Losartan may be blunted by the non-steroidal anti-inflammatory drug Indomethacin.

Hydrochlorothiazide: When administered concurrently, the following drugs may interact with Thiazide diuretics: alcohol, barbiturates, or narcotics-potentiation of orthostatic hypotension may occur.

Antidiabetic drugs (oral agents and Insulin): dosage adjustment of the antidiabetic drug may be required.

Other antihypertensive drugs: additive effect or potentiation.

Cholestyramine and colestipol resins: absorption of Hydrochlorothiazide is impaired in the presence of anionic exchange resins

Contraindications

The combination of Losartan and Hydrochlorothiazide is contraindicated in patients who are hypersensitive to any component of this product. Because of the Hydrochlorothiazide component, this product is contraindicated in patients with anuria or hypersensitivity to other sulfonamide-derived drugs.

Side Effects

Side-effects are usually mild. Symptomatic hypotension including dizziness may occur, particularly in patients with intravascular volume depletion (e.g. those taking high-dose diuretics). Hyperkalaemia occurs occasionally; angioedema has also been reported with some angiotensin-II receptor antagonists. Vertigo; less commonly gastro-intestinal disturbances, angina, palpitation, oedema, dyspnoea, headache, sleep disorders, malaise, urticaria, pruritus, rash; rarely hepatitis, atrial fibrillation, cerebrovascular accident, syncope, paraesthesia; also reported pancreatitis, anaphylaxis, cough, depression, erectile dysfunction, anaemia, thrombocytopenia, hyponatraemia, arthralgia, myalgia, renal impairment, rhabdomyolysis, tinnitus, photosensitivity, and vasculitis (including Henoch-Schonlein purpura)

Precautions & Warnings

• Hypersensitivity: Angiooedema
• Periodic determination of serum electrolytes to detect possible electrolyte imbalance should be performed at appropriate intervals
• Hypokalemia may rarely develop, especially with brisk diuresis, when severe cirrhosis is present, or after prolonged therapy
• Impaired renal function and
• Symptomatic hypotension

Overdose Effects

Losartan Potassium: Limited data are available in regard to overdosage in humans. The most likely manifestation of overdosage would be hypotension and tachycardia; bradycardia could occur from parasympathetic (vagal) stimulation. If symptomatic hypotension should occur, supportive treatment should be instituted. Neither losartan nor its metabolite can be removed by hemodialysis.

Hydrochlorothiazide: The most common signs and symptoms observed are those caused by electrolyte depletion (hypokalemia, hypochloremia, and dehydration resulting from excessive diuresis. If digitalis has also been administered, hypokalemia, may accentuate cardiac arrhythmias. The degree to which Hydrochlorothiazide is removed by hemodialysis has not been established.

Therapeutic Class

Combined antihypertensive preparations

Storage Conditions

Do not store above 30°C. Keep out of the reach of children.