Losartan potassium hydrochlorothiazide is a medication prescribed to treat hypertension, or high blood pressure. Decreasing a patient's high blood pressure can help prevent heart attacks and strokes. Losartan potassium hydrochlorothiazide is a combination drug, containing both a thiazide diuretic, or water pill, as well as an angiotensin receptor blocker, called losartan. This drug works by relaxing and widening the blood vessels, as well as increasing the amount of water and salt processed by the kidneys. Excess water and salt may then be excreted in urine.
Adults will typically take an initial dose of 50 milligrams (mg) of losartan and 12.5 mg of hydrochlorothiazide once daily, which may be increased as needed. It may be taken with or without food. Although most patients should consume plenty of water to avoid dehydration, patients with kidney disease should closely follow their doctor's recommended fluid intake. Since this medication results in an increased amount of urine, it is recommended that patients take their dose before evening to avoid disrupted sleep.
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Some side effects may occur with the use of losartan potassium hydrochlorothiazide, which should be reported to the doctor if they become bothersome. These side effects may include blurred vision, dizziness, and lightheadedness. Back pain, nausea, and diarrhea may also occur. Some patients have reported tiredness, numbness or tingling, and a stuffy nose. In addition, this drug will cause an increased amount of urine when the patient begins treatment; however, this will decrease as the body adjusts to the medicine.
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More serious side effects from losartan potassium hydrochlorothiazide require a doctor's immediate care. These may rarely include a rapid heartbeat, abdominal pain, and confusion. Fainting, unusual thirst, and weakness have also been reported. Other patients have experienced jaundice, seizures, and muscle pain. Signs of a possible allergic reaction can include severe dizziness, swelling of the facial area, and difficulty breathing, as well as a rash.
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Certain precautions should be followed while using losartan potassium hydrochlorothiazide. Hot weather, exercise, and the consumption of alcohol can worsen side effects. Patients should avoid excessive exposure to sunlight, as they will be more susceptible to sunburns. Diabetics may notice that losartan potassium hydrochlorothiazide increases blood sugar levels, which may become dangerous unless it is managed. Patients may be prescribed a potassium tablet to take with this drug; however, they should not take additional potassium, including a salt substitute or other product containing potassium.
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Before using losartan potassium hydrochlorothiazide, patients must disclose their other medical conditions, medications, and supplements. Women who are pregnant or breastfeeding should never use this drug. It is also contraindicated for use by those who have urinary problems, kidney disease, and high cholesterol. Losartan potassium hydrochlorothiazide may interact with other drugs, including corticosteroids, narcotic pain relievers, and muscle relaxants.