Hyzaar (losartan / hydrochlorothiazide) is a combination medication that contains two first-choice options for lowering blood pressure. This medication is taken by mouth once daily. Like other blood pressure medications, Hyzaar (losartan / hydrochlorothiazide) can cause you to feel dizzy, especially when you first start this medication or when your provider raises your dose.
High blood pressure
Lower the risk of stroke in people with high blood pressure and an enlarged left ventricle of the heart
Hyzaar (losartan / hydrochlorothiazide) is a combination of two medications that work together to lower blood pressure:
Losartan is an angiotensin II receptor blocker (ARB). It works by blocking angiotensin II, a hormone that raises your blood pressure, from attaching to its receptors (signaling proteins). In doing so, losartan lowers your blood pressure by relaxing the blood vessels.
Hydrochlorothiazide is a thiazide diuretic (water pill). It works in your kidneys to remove extra water and certain electrolytes (like sodium and potassium). This helps lower blood pressure.
Source:Â Daily
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Rare
Black, tarry stools
blood in the urine or stools
cough or hoarseness accompanied by chills or fever, lower back or side pain, or painful or difficult urination
fainting
pinpoint red spots on the skin
pounding heartbeat
severe stomach pain, nausea, and vomiting
skin rash
swelling of the feet or lower legs
unusual bleeding or bruising
Incidence not known
Bleeding gums
blistering, peeling, loosening of the skin
blurred vision
chest pain or tightness
chills
coma
confusion
dark-colored urine
decreased frequency of urine
decreased urine output
difficulty swallowing
dizziness
fast, irregular, pounding, or racing heartbeat or pulse
increased sensitivity of the skin to sunlight
increased thirst
irritability
joint or muscle pain
large, flat, blue, or purplish patches in the skin
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or sex organs
light-colored stools
loss of appetite
lower back or side pain
muscle cramps, pain, spasms, stiffness, or twitching
nausea or vomiting
numbness or tingling in the hands, feet, or lips
painful knees and ankles
persistent non-healing sore
pink growth
puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
raised red swellings on the skin, the buttocks, legs, or ankles
red, irritated eyes
red skin lesions, often with a purple center
reddish patch or irritated area
redness or other discoloration of the skin
restlessness
seizures
severe sunburn
shiny bump
sores, ulcers, or white spots in the mouth or on the lips
swelling of the face, ankles, or hands
trouble breathing
upper right abdominal or stomach pain
unusual tiredness or weakness
weak or irregular heartbeat
white, yellow or waxy scar-like area
yellow eyes and skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Rare
Incidence not known
Acid or sour stomach
belching
change or loss of taste
difficulty having a bowel movement (stool)
general feeling of discomfort or illness
inability to have or keep an erection
indigestion
loss in sexual ability, desire, drive, or performance
trouble sleeping
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Contains two first-choice blood pressure medications
Convenient to take a combination of two medications in one pill taken just once a day
Protects your kidneys, which is especially useful for people with diabetes or mild-to-moderate kidney disease
Taken by mouth once per day
Can make you urinate more often
Must be avoided in pregnant females
More difficult to customize the dose since Hyzaar (losartan / hydrochlorothiazide) is a combination of two medications
Only available as a tablet
Take Hyzaar (losartan / hydrochlorothiazide) with or without food at any time of day. If it hurts your stomach, try taking it with food to help.
You might feel dizzy when you start taking Hyzaar (losartan / hydrochlorothiazide), and when the dose is raised. This should get better over time as you continue taking the medication and your body gets used to your new blood pressure. Stand up slowly and carefully from a sitting or lying down position to avoid falling.
If you feel dizzy, lightheaded, feeling like you're going to faint, tired, or confused while taking Hyzaar (losartan / hydrochlorothiazide), your blood pressure might be too low. Make sure to hold onto something when standing and slowly sit or lie down if you can. Call your provider if this happens because your dose might need to be changed.
Make sure to mark your calendar with your appointments to see your provider and to get any blood work done when you take Hyzaar (losartan / hydrochlorothiazide). Your provider may order tests (e.g., potassium level, kidney function, blood pressure) during treatment and might change your dose of Hyzaar (losartan / hydrochlorothiazide) based on your lab results.
Take Hyzaar (losartan / hydrochlorothiazide) exactly as prescribed. Don't change your dose or suddenly stop taking the medication without talking to your provider first. Doing so can cause your blood pressure to rise quickly. If you want to stop Hyzaar (losartan / hydrochlorothiazide), ask your provider if it's safe to do so. You might need to lower your dose slowly over time before you can completely stop taking it.
Hyzaar (losartan / hydrochlorothiazide) can raise your potassium levels, which can be serious. Ask your provider if you need to limit eating foods that are high in potassium. Contact your provider if you experience nausea, vomiting, or muscle weakness because these might be signs of high potassium levels.
It's recommended you measure and record your blood pressure at home and bring a record to your medical appointments. This will help your provider see how well the medication is working for you and guide any dose changes.
Make sure to have a healthy diet, including a low-salt diet, while taking Hyzaar (losartan / hydrochlorothiazide) to help lower your blood pressure. Depending on your risk factors and other medical problems, it's possible you might be able to stop taking Hyzaar (losartan / hydrochlorothiazide) if your blood pressure gets within goal.
If you accidentally miss a dose of Hyzaar (losartan / hydrochlorothiazide), take it as soon as you remember. But if it's close to your next dose, then skip that dose and take your next dose at your regularly scheduled time. Don't take 2 doses of Hyzaar (losartan / hydrochlorothiazide) at the same time to make up for any missed doses, because this could lead to dangerous side effects.
Hyzaar (losartan / hydrochlorothiazide) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Hyzaar (losartan / hydrochlorothiazide) shouldn't be taken by pregnant females because it can cause severe harm and even death to unborn babies. If you find out that you're pregnant while taking Hyzaar (losartan / hydrochlorothiazide), stop and let your provider know right away. If you're pregnant before starting Hyzaar (losartan / hydrochlorothiazide) or thinking of becoming pregnant during treatment, discuss with your provider about safer options to treat your blood pressure.
Risk factors: Not enough fluid in your body | Having diarrhea or vomiting for a long time | Low salt levels in your body | Taking higher doses of diuretic medications
Hyzaar (losartan / hydrochlorothiazide) can cause your blood pressure to drop too much, which can make you feel dizzy, tired, or lightheaded. This side effect is more common when you first start Hyzaar (losartan / hydrochlorothiazide) or when the dose is raised. Make sure to stay well-hydrated. If your blood pressure drops too much and you feel dizzy, make sure to sit down slowly while holding onto something and let your provider know. If you fall and hit your head, get medical help right away. If you feel dizzy, lightheaded, faint, tired, or confused while taking Hyzaar (losartan / hydrochlorothiazide), contact your provider right away.
Risk factors: Severe heart failure | Kidney problems | Not enough fluid in your body | Taking other medications that can cause kidney damage | History of narrow heart valves (aortic stenosis)
Sometimes, Hyzaar (losartan / hydrochlorothiazide) can affect your kidneys and cause them to not work as well. The risk is higher for people who have certain types of kidney problems, such as renal artery stenosis or very severe heart failure. Your provider might order lab tests every so often to make sure your kidneys are healthy and working properly. If you develop kidney problems, or if your kidney problems worsen while taking Hyzaar (losartan / hydrochlorothiazide), your provider might recommend that you stop taking this medication. Let your provider know if you're urinating less often than usual, as this could be a sign that your kidneys aren't working as well.
Hyzaar (losartan / hydrochlorothiazide) can affect the level of certain electrolytes in your body, including sodium, potassium, and magnesium. Your provider might order bloodwork regularly while you're taking this medication to make sure your electrolyte levels are in a safe range. Let your provider know if you experience a fast heart beat, weakness, low energy, muscle pain or cramps, less urination than usual, nausea, or vomiting. These can be signs of electrolyte changes in your body.
In addition, hydrochlorothiazide can change the way your body responds to blood sugar. It can also raise your cholesterol levels. Your provider might also check your blood sugar and cholesterol levels regularly while you're taking this medication.
Risk factors: Sulfa or penicillin allergies
Though rare, some people experience vision changes within hours or weeks after starting Hyzaar (losartan / hydrochlorothiazide) because of the hydrochlorothiazide part of the medication. Tell your provider right away about any vision changes or eye pain and stop taking Hyzaar (losartan / hydrochlorothiazide) as soon as possible. In some cases, surgery might be required to avoid permanent vision loss.
Rarely, Hyzaar (losartan / hydrochlorothiazide) can cause worsening of or new lupus. Let your provider know if you notice a rash across your cheeks and nose or feel very tired.
The typical dose of Hyzaar ranges from 50 mg/12.5 mg (losartan/hydrochlorothiazide) to 100 mg/25 mg (losartan/hydrochlorothiazide) by mouth once daily.
Your provider will adjust your dose based on how well it's helping your blood pressure and if you're having side effects.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Not producing urine
Taking at the same time as aliskiren (Tekturna) in people with diabetes (high blood sugar)
High blood pressure
Lower the risk of stroke in people with high blood pressure and an enlarged left ventricle of the heart
High blood pressure
High blood pressure in adults
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American Heart Association. (2020). What is left ventricular hypertrophy (LVH)?
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Hermida, R. C., et al. (2020). Bedtime hypertension treatment improves cardiovascular risk reduction: The Hygia Chronotherapy Trial. European Heart Journal.
Hill, R. D., et al. (2022). Angiotensin II Receptor Blockers (ARB). StatPearls.
Mackenzie, I. S., et al. (2022). Cardiovascular outcomes in adults with hypertension with evening versus morning dosing of usual antihypertensives in the UK (TIME study): A prospective, randomised, open-label, blinded-endpoint clinical trial. The Lancet.
Macleods Pharmaceuticals Limited. (2023). LOSARTAN POTASSIUM AND HYDROCHLOROTHIAZIDE - losartan potassium and hydrochlorothiazide tablet, film coated [package insert]. DailyMed.
Whelton, P. K., et al. (2017). 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/ PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: A report of the American College of Cardiology/American Heart Association Task Force on clinical practice guidelines. Hypertension. Â
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