Losartic (Losartan Potassium-Hydrochlorothiazide) is a combination of an Angiotensin II receptor antagonist and a Thiazide diuretic used to treat high blood pressure. Losartic is also used to lower the risk of stroke in certain people with heart disease.
 

Each tablet Losartic contains Losartan Potassium 50 mg + Hydrochlorothiazide 12.5 mg.

Adults:
Losartic may be used alone or in combination with other antihypertensive agents for the treatment of:
Hypertension
Losartic is indicated for the treatment of hypertension. This fixed dose combination is indicated for initial therapy of hypertension, when the hypertension is severe enough to initiate combination therapy in these patients.

Hypertensive Patients with Left Ventricular Hypertrophy
Losartic is indicated to reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy, but there is evidence that this benefit does not apply to Black patients

Children and adolescents
Safety and effectiveness of Losartic in pediatric patients have not been established.

Pregnancy& breast-feeding 
 Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue Losartic as soon as possible.

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

It is not known whether Losartan is excreted in human milk, but significant levels of losartan and its active metabolite were shown to be present in rat milk. Thiazides appear in human 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 account the importance of the drug to the mother.

Adults:
Hypertension:
The usual starting dose of Losartic is (Losartan 50 mg/Hydrochlorothiazide 12.5 mg) once daily. The dosage can be increased after 3 weeks of therapy to a maximum of 100/25 (losartan 100 mg/hydrochlorothiazide 25 mg) two tablets once daily as needed to control blood pressure.
Initiate a patient whose blood pressure is not adequately controlled with losartan 50 mg monotherapy with Losartic once daily. If blood pressure remains uncontrolled after about 3 weeks of therapy, the dosage may be increased to two tablets of Losartic once daily.

Hypertensive Patients with Left Ventricular Hypertrophy:
In patients whose blood pressure is not adequately controlled on 50 mg losartan potassium, initiate treatment with Losartic. If additional blood pressure reduction is needed, increase the dose to two tablets of Losartic. For further blood pressure reduction add other antihypertensives.