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Patient Information on Losartan Potassium with Hydrochlorothiazide

written by: R. Elizabeth C. Kitchen•edited by: Leigh A. Zaykoski•updated: 10/29/2009

This article focuses on providing all of the important patient information on losartan potassium with hydrochlorothiazide.

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    Losartan potassium with hydrochlorothiazide is a type of prescription medication used in the treatment of certain cardiovascular disorders. This medication contains two drugs: hydrochlorothiazide (a diuretic/water pill) and losartan (an angiotensin receptor blocker). This drug is marked under the brand name Hyzaar.

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    This medication is mainly used to reduce high blood pressure by relaxing the blood vessels which results in them widening. The losartan component does this by blocking angiotensin, a hormone. By lowering blood pressure it can also help to prevent kidney problems, heart attacks, and strokes. The thiazide, the diuretic component, reduces the amount of salt and water in the body, by increasing the amount of urine the body makes. This drug can also be used to protect diabetes-related kidney damage and to treat congestive heart failure. The losartan component is also beneficial to patients with an enlarged heart and hypertension because it can help to reduce their stroke risk.

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    All patients should thoroughly read the attached patient pamphlet that comes with this medication before their first dose. This is a powerful medication and must be taken exactly as directed. All questions should be asked prior to taking the first dose. This medication is typically taken once per day by mouth. It can be taken without food or with food if it causes stomach upset. It must be taken daily and at the same time every day.

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    Patients who are allergic to ACE inhibitors should tell their doctor before taking this drug. Patients with certain medical conditions may not be able to take this drug. These medical conditions include urinary problems, asthma, kidney disease, high cholesterol, high triglycerides, liver disease, heart problems, lupus, sodium imbalance, severe body fluid loss (through vomiting, excessive sweating, or diarrhea), potassium imbalance, gout, calcium imbalance, magnesium imbalance, and other electrolyte/mineral imbalances.

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    Side Effects

    The common side effects often go away with time, but if they worsen or persist the patient should contact their physician. The common side effects of losartan potassium with hydrochlorothiazide include dizziness, stuffy nose, blurred vision, and lightheadedness. Serious side effects are unlikely, but they do occur. Patients who experience the serious side effects should contact their doctor immediately. The serious side effects include unusual thirst, reduced sexual ability, weakness, fainting, fast heartbeat, confusion, significant change in amount of urine, muscle pain, seizures, unusual fatigue, abdominal/stomach pain, dark urine, or yellowing of the eyes or skin. An allergic reaction is unlikely, but can occur. The signs include trouble breathing, rash, severe dizziness, itching, and swelling of the throat, face, tongue and lips.

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    Drug Interactions

    Patients taking salt or potassium supplements should consult their physician before starting this medication. Patients taking certain medications may not be able to use this drug. These medications include dofetilide, cisapride, rifampin, corticosteroids, probenecid, diazoxide, lithium, digoxin, fluconazole, drugs that may increase dizziness (such as narcotic analgesics and phenobarbitol), and drugs that are affected by the urine's acid level (such as methenamine, amphetamine, and quinidine). Certain over-the-counter medications may also interact and these include non-steroidal anti-inflammatory drugs (such as naproxen and ibuprofen), diet aids, cold and cough products, and low-dose aspirin.

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    Risks and Warnings

    This medication can cause dehydration so patients should consume an adequate amount of fluids. If patients are following a restricted fluid plan they should consult their doctor about how much fluids they should consume daily. This medication may cause a patients potassium level to decrease leading to serious side effects such as very slow heartbeat, muscle cramping and muscle weakness. This medication cannot be used by pregnant women because it can be fatal to a unborn fetus. Patients with diabetes should tell their doctor prior to starting these medication because it may affect blood sugar levels. Signs of high blood sugar include unusual tiredness, increased thirst, fruity breath odor, and vision changes. Patients should limit alcohol use and avoid dangerous activities because this medication can cause dizziness. Patients scheduled for surgery should tell their doctor they are taking this medication prior to having the procedure. This medication can increase sun sensitivity. This medication does pass into breast milk and should not be used by breastfeeding women.

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    RxList. (2009). Losartan Potassium with Hydrochlorothiazide. Retrieved on October 22, 2009 from Website: