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The class of drugs called angiotensin receptor blockers (ARBs), as the class name suggests, are drugs that block the action of angiotensin. Specifically, ARBs preve"...
(losartan potassium and hydrochlorothiazide) Tablets
When pregnancy is detected, discontinue HYZAAR as soon as possible. Drugs that act directly on the renin-angiotensin system can cause injury and death to the developing fetus [see WARNINGS AND PRECAUTIONS].
HYZAAR 50/12.5 (losartan potassium-hydrochlorothiazide), HYZAAR 100/12.5 (losartan potassiumhydrochlorothiazide) and HYZAAR 100/25 (losartan potassium-hydrochlorothiazide) tablets combine an angiotensin II receptor blocker acting on the AT 1 receptor subtype and a diuretic, hydrochlorothiazide.
Losartan potassium, a non-peptide molecule, is chemically described as 2-butyl-4-chloro-1-[p-(o-1Htetrazol-5-ylphenyl)benzyl]imidazole-5-methanol monopotassium salt. Its empirical formula is C22H22ClKN6O, and its structural formula is:
Losartan potassium is a white to off-white free-flowing crystalline powder with a molecular weight of 461.01. It is freely soluble in water, soluble in alcohols, and slightly soluble in common organic solvents, such as acetonitrile and methyl ethyl ketone.
Oxidation of the 5-hydroxymethyl group on the imidazole ring results in the active metabolite of losartan.
Hydrochlorothiazide is 6-chloro-3,4-dihydro-2H-1,2,4-benzothiadiazine-7-sulfonamide 1,1-dioxide. Its empirical formula is C7H8ClN3O4S2 and its structural formula is:
Hydrochlorothiazide is a white, or practically white, crystalline powder with a molecular weight of 297.74, which is slightly soluble in water, but freely soluble in sodium hydroxide solution.
HYZAAR is available for oral administration in three tablet combinations of losartan and hydrochlorothiazide. HYZAAR 50/12.5 contains 50 mg of losartan potassium and 12.5 mg of hydrochlorothiazide. HYZAAR 100/12.5 contains 100 mg of losartan potassium and 12.5 mg of hydrochlorothiazide. HYZAAR 100/25 contains 100 mg of losartan potassium and 25 mg of hydrochlorothiazide. Inactive ingredients are microcrystalline cellulose, lactose hydrous, pregelatinized starch, magnesium stearate, hydroxypropyl cellulose, hypromellose, and titanium dioxide. HYZAAR 50/12.5 and HYZAAR 100/25 also contain D&C yellow No. 10 aluminum lake. HYZAAR 50/12.5, HYZAAR 100/12.5, and HYZAAR 100/25 may also contain carnauba wax.
HYZAAR 50/12.5 contains 4.24 mg (0.108 mEq) of potassium, HYZAAR 100/12.5 contains 8.48 mg (0.216 mEq) of potassium, and HYZAAR 100/25 contains 8.48 mg (0.216 mEq) of potassium.
What are the possible side effects of hydrochlorothiazide and losartan (Hyzaar)?
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
In rare cases, hydrochlorothiazide and losartan 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.
Stop using this medication and call your doctor at once if you have a serious...
What are the precautions when taking losartan potassium-hydrochlorothiazide (Hyzaar)?
Before taking this medication, tell your doctor or pharmacist if you are allergic to losartan or hydrochlorothiazide; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: gout, kidney disease, liver disease, lupus, severe loss of body water and minerals (dehydration).
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Severe sweating, diarrhea, or vomiting can increase the risk for lightheadedness or a serious...
Last reviewed on RxList: 12/26/2015
This monograph has been modified to include the generic and brand name in many instances.
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