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Hyzaar

Generic Name: hydrochlorothiazide and losartan (HYE droe KLOR oh THYE a zide and loe SAR tan)
Brand Names: Hyzaar

Medically reviewed by P. Thornton, DipPharm Last updated on May 7, 2019.

What is Hyzaar?

Hyzaar contains a combination of hydrochlorothiazide and losartan. Hydrochlorothiazide is a thiazide diuretic (water pill) that helps prevent your body from absorbing too much salt, which can cause fluid retention.

Losartan is an angiotensin II receptor antagonist (sometimes called an ARB blocker). Losartan keeps blood vessels from narrowing, which lowers blood pressure and improves blood flow.

Hyzaar is used to treat high blood pressure (hypertension).

Hyzaar is also used to lower the risk of stroke in certain people with heart disease.

Important Information

Do not use Hyzaar if you are pregnant, and tell your doctor right away if you become pregnant. This medicine can cause injury or death to the unborn baby during your second or third trimester.

You should not use this medicine if you are unable to urinate.

If you have diabetes, do not use Hyzaar together with any medication that contains aliskiren (a blood pressure medicine).

You may also need to avoid taking Hyzaar with aliskiren if you have kidney disease.

In rare cases, Hyzaar can cause a condition that results in the breakdown of skeletal muscle tissue, leading to kidney failure. Call your doctor right away if you have unexplained muscle pain, tenderness, or weakness especially if you also have fever, unusual tiredness, and dark colored urine.

Before taking this medicine

You should not use Hyzaar if you are allergic to hydrochlorothiazide or losartan, if you are unable to urinate.

Do not use if you are pregnant, and tell your doctor right away if you become pregnant. Hyzaar can cause injury or death to the unborn baby if you take the medicine during your second or third trimester.

To make sure this medicine is safe for you, tell your doctor if you have ever had:

  • lupus;

  • liver or kidney disease;

  • asthma or allergies;

  • diabetes;

  • gout;

  • congestive heart failure;

  • glaucoma;

  • low or high levels of potassium in your blood;

  • high cholesterol or triglyceride levels; or

  • an allergy to penicillin or sulfa drugs.

You should not breast-feed while using this medicine.

How should I take Hyzaar?

Take Hyzaar exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose.

Your blood pressure will need to be checked often.

Call your doctor if you are sick with vomiting or diarrhea, or if you are sweating more than usual. You can easily become dehydrated while taking this medicine. This can lead to very low blood pressure, a serious electrolyte imbalance, or kidney failure.

If you need surgery or medical tests, tell the surgeon ahead of time that you are using Hyzaar.

If you have high blood pressure, keep using Hyzaar even if you feel well. High blood pressure often has no symptoms. You may need to use blood pressure medicine for the rest of your life.

Store at room temperature away from moisture, heat, and light.

Hyzaar dosing information

Usual Adult Dose for Hypertension:

HYPERTENSION:
Hydrochlorothiazide 12.5 to 25 mg-Losartan 50 to 100 mg orally once a day

Maximum dose: Hydrochlorothiazide 25 mg-Losartan 100 mg orally once a day

Comments:
-A patient whose blood pressure is not adequately controlled with hydrochlorothiazide or losartan monotherapy may be switched to hydrochlorothiazide 12.5 mg-losartan 50 mg orally once a day.
-May increase dose if blood pressure remains uncontrolled after about 3 weeks.

Use: Treatment of hypertension. This drug is not indicated for initial therapy except when hypertension is severe enough that the benefit of achieving prompt blood pressure control exceeds the risk of initiating combination therapy.

SEVERE HYPERTENSION:
Initial treatment: Hydrochlorothiazide 12.5 mg-Losartan 50 mg orally once a day; if blood pressure remains uncontrolled after 2 to 4 weeks, may initiate maximum dose.

Maximum dose: Hydrochlorothiazide 25 mg-Losartan 100 mg orally once a day

HYPERTENSION WITH LEFT VENTRICULAR HYPERTROPHY:
Initial therapy: Losartan monotherapy; if blood pressure remains uncontrolled, may initiate this drug.

Add-on therapy: Hydrochlorothiazide 12.5 mg-Losartan 50 mg orally once a day; if blood pressure remains uncontrolled, initiate hydrochlorothiazide 12.5 mg-losartan 100 mg orally once a day, followed by hydrochlorothiazide 25 mg-losartan 100 mg orally once a day, if needed.

Use: 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.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Hyzaar?

Do not use potassium supplements or salt substitutes, unless your doctor has told you to.

Drinking alcohol can further lower your blood pressure and may cause side effects.

Avoid becoming overheated or dehydrated during exercise, in hot weather, or by not drinking enough fluids.

Hyzaar side effects

Get emergency medical help if you have signs of an allergic reaction to Hyzaar: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;

  • irregular heartbeats;

  • eye pain, vision problems;

  • kidney problems - little or no urination, rapid weight gain, swelling in your hands, feet, or ankles;

  • new or worsening symptoms of lupus - joint pain, and a skin rash on your cheeks or arms that worsens in sunlight; or

  • signs of an electrolyte imbalance - increased thirst or urination, confusion, vomiting, constipation, muscle pain, leg cramps, irregular heartbeats, numbness or tingling, severe weakness, loss of movement, feeling jittery or unsteady.

Common Hyzaar side effects may include:

  • dizziness;

  • back pain; or

  • cold symptoms such as stuffy nose, sneezing, sore throat.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Hyzaar?

If you also take cholestyramine or colestipol, take your Hyzaar dose 4 hours before or 4 to 6 hours after you take the other medicine.

Tell your doctor about all your other medicines, especially:

This list is not complete. Other drugs may interact with hydrochlorothiazide and losartan, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Hyzaar only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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