Losartan and hydrochlorothiazide (Oral)
Generic name: losartan and hydrochlorothiazide [ loe-SAR-tan-poe-TAS-ee-um, hye-droe-klor-oh-THYE-a-zide ]
Brand name: Hyzaar
Drug class: Angiotensin II inhibitors with thiazides
Medically reviewed by Drugs.com. Last updated on Oct 12, 2024.
Drugs that act directly on the renin-angiotensin system can cause injury or death to the developing fetus. Stop therapy as soon as possible when pregnancy is detected .
Uses for losartan and hydrochlorothiazide
Losartan and hydrochlorothiazide combination is used alone or together with other medicines to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. Lowering blood pressure may reduce the risk of strokes and heart attacks.
Losartan and hydrochlorothiazide combination is also used to reduce the risk of stroke in patients with high blood pressure and enlargement of the heart.
Losartan is an angiotensin II receptor blocker (ARB). It works by blocking a substance in the body that causes the blood vessels to tighten. Losartan relaxes the blood vessels and lowers the blood pressure. A lower blood pressure will increase the supply of blood and oxygen to the heart.
Hydrochlorothiazide is a thiazide diuretic (water pill) . It reduces the amount of water in the body by increasing the flow of urine, which helps lower the blood pressure.
This medicine is available only with your doctor's prescription.
Before using losartan and hydrochlorothiazide
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Allergies
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Pediatric
Appropriate studies have not been performed on the relationship of age to the effects of losartan and hydrochlorothiazide combination in the pediatric population. Safety and efficacy have not been established.
Geriatric
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of losartan and hydrochlorothiazide combination in the elderly. However, elderly patients are more likely to have unwanted side effects, which may require caution in patients receiving losartan and hydrochlorothiazide combination.
Breast Feeding
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with Medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
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.
- Aliskiren
- Dofetilide
- Sparsentan
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.
- Acarbose
- Aceclofenac
- Acemetacin
- Acetyldigoxin
- Albiglutide
- Albuterol
- Alogliptin
- Amphetamine
- Amtolmetin Guacil
- Arsenic Trioxide
- Aspirin
- Benazepril
- Benzphetamine
- Bromfenac
- Bromocriptine
- Bufexamac
- Buprenorphine
- Canagliflozin
- Capecitabine
- Captopril
- Celecoxib
- Ceritinib
- Chlorpropamide
- Choline Salicylate
- Cilazapril
- Clarithromycin
- Clonixin
- Codeine
- Dapagliflozin
- Deslanoside
- Desmopressin
- Dexibuprofen
- Dexketoprofen
- Dextroamphetamine
- Diclofenac
- Diflunisal
- Digitalis
- Digitoxin
- Digoxin
- Dipyrone
- Droperidol
- Droxicam
- Dulaglutide
- Empagliflozin
- Enalapril
- Enalaprilat
- Entacapone
- Etodolac
- Etofenamate
- Etoricoxib
- Exenatide
- Felbinac
- Fenoprofen
- Fepradinol
- Feprazone
- Flecainide
- Floctafenine
- Flufenamic Acid
- Flurbiprofen
- Formoterol
- Fosinopril
- Furosemide
- Glimepiride
- Glipizide
- Glyburide
- Ibuprofen
- Indomethacin
- Insulin
- Insulin Aspart, Recombinant
- Insulin Bovine
- Insulin Degludec
- Insulin Detemir
- Insulin Glulisine
- Ketanserin
- Ketoprofen
- Ketorolac
- Levomethadyl
- Linagliptin
- Liraglutide
- Lisdexamfetamine
- Lisinopril
- Lithium
- Lixisenatide
- Lornoxicam
- Loxoprofen
- Lumiracoxib
- Mavacamten
- Meclofenamate
- Mefenamic Acid
- Meloxicam
- Methamphetamine
- Methotrexate
- Metildigoxin
- Miglitol
- Moexipril
- Morniflumate
- Nabumetone
- Naproxen
- Nateglinide
- Nepafenac
- Niflumic Acid
- Nimesulide
- Nimesulide Beta Cyclodextrin
- Ouabain
- Oxaprozin
- Oxyphenbutazone
- Parecoxib
- Perindopril
- Phenobarbital
- Phenylbutazone
- Piketoprofen
- Pioglitazone
- Piroxicam
- Porfimer
- Potassium Citrate
- Potassium Phosphate
- Pramlintide
- Primidone
- Proglumetacin
- Propyphenazone
- Proquazone
- Proscillaridin
- Quinapril
- Ramipril
- Repaglinide
- Rofecoxib
- Rosiglitazone
- Salicylic Acid
- Salsalate
- Saxagliptin
- Sitagliptin
- Sodium Salicylate
- Sotalol
- Spirapril
- Sulindac
- Tacrolimus
- Tapentadol
- Tenoxicam
- Tiaprofenic Acid
- Tolazamide
- Tolbutamide
- Tolfenamic Acid
- Tolmetin
- Topiramate
- Trandolapril
- Trimethoprim
- Valdecoxib
- Vildagliptin
- Zofenopril
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.
- Aceclofenac
- Acemetacin
- Aminolevulinic Acid
- Amtolmetin Guacil
- Bepridil
- Bromfenac
- Bufexamac
- Carbamazepine
- Celecoxib
- Cholestyramine
- Choline Salicylate
- Clonixin
- Dexibuprofen
- Dexketoprofen
- Diclofenac
- Diflunisal
- Dipyrone
- Droxicam
- Etodolac
- Etofenamate
- Etoricoxib
- Felbinac
- Fenoprofen
- Fepradinol
- Feprazone
- Floctafenine
- Fluconazole
- Flufenamic Acid
- Flurbiprofen
- Ginkgo
- Gossypol
- Ibuprofen
- Indomethacin
- Ketoprofen
- Ketorolac
- Licorice
- Lornoxicam
- Loxoprofen
- Lumiracoxib
- Meclofenamate
- Mefenamic Acid
- Meloxicam
- Morniflumate
- Nabumetone
- Naproxen
- Nepafenac
- Niflumic Acid
- Nimesulide
- Nimesulide Beta Cyclodextrin
- Oxaprozin
- Oxyphenbutazone
- Parecoxib
- Phenylbutazone
- Piketoprofen
- Piroxicam
- Pranoprofen
- Proglumetacin
- Propionic Acid
- Propyphenazone
- Proquazone
- Rifampin
- Rofecoxib
- Salicylic Acid
- Salsalate
- Sodium Salicylate
- Sulindac
- Tenoxicam
- Tiaprofenic Acid
- Tolfenamic Acid
- Tolmetin
- Valdecoxib
Interactions with Food/Tobacco/Alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Angioedema (an allergic reaction) with other blood pressure medicines (eg, benazepril, enalapril, lisinopril, Lotrel®, Vasotec®, Zestoretic®, Zestril®), history of—Use may cause this condition to reoccur.
- Anuria (not able to form urine) or
- Diabetic patients who are also taking aliskiren (Tekturna®) or
- Patients with kidney disease who are also taking aliskiren (Tekturna®)—Should not be used in patients with these conditions.
- Asthma, or history of—May increase likelihood of having an allergic reaction.
- Congestive heart failure, severe—Use may lead to kidney problems.
- Diabetes or
- Electrolyte imbalances (eg, high or low calcium, magnesium, potassium, or sodium in the body) or
- Fluid imbalances (caused by dehydration, vomiting, or diarrhea) or
- Glaucoma, secondary angle closure or
- Gout or
- Hypercholesterolemia (high cholesterol in the blood) or
- Hypertriglyceridemia (high triglycerides or fats in the blood) or
- Kidney disease or
- Liver disease (including cirrhosis) or
- Myopia (changes in the eyeball causing vision problems), acute or
- Systemic lupus erythematosus (an autoimmune disorder)—Use with caution. May make these conditions worse.
- Sympathectomy—Blood pressure–lowering effects of this medicine may be increased.
Proper use of losartan and hydrochlorothiazide
In addition to the use of the medicine your doctor has prescribed, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium (salt). Your doctor will tell you which of these is most important for you. You should check with your doctor before changing your diet.
Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well.
Remember that this medicine will not cure your high blood pressure but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease.
This medicine comes with a patient information insert. Read and follow the instructions carefully. Ask your doctor if you have any questions.
Swallow the tablet whole. Do not break, crush, or chew it. This medicine may be taken with or without food.
If you also use cholestyramine or colestipol, take these at least 4 hours after you take this medicine.
Dosing
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage form (tablets):
- For high blood pressure:
- Adults—At first, one tablet once a day. Your doctor may increase your dose as needed. However, the dose is usually not more than 100 mg of losartan and 25 mg of hydrochlorothiazide per day.
- Children—Use and dose must be determined by your doctor.
- For lowering risk of stroke in patients with high blood pressure and enlargement of the heart:
- Adults—At first, one tablet once a day. Your doctor may increase your dose as needed.
- Children—Use and dose must be determined by your doctor.
- For high blood pressure:
Missed Dose
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Storage
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Related/similar drugs
amlodipine, lisinopril, metoprolol, losartan, furosemide, hydrochlorothiazide
Precautions while using losartan and hydrochlorothiazide
It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood and urine tests may be needed to check for unwanted effects.
Using this medicine while you are pregnant can harm your unborn baby, especially in your second or third trimester. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away. You may need to stop using this medicine.
This medicine may cause dizziness, lightheadedness, or fainting, especially when you get up suddenly from a lying or sitting position. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are dizzy. If you feel dizzy, lie down so you do not faint. Then sit for a few moments before standing to prevent the dizziness from returning.
Check with your doctor right away if you become sick while taking this medicine, especially if you have severe or continuing nausea or vomiting, or diarrhea that does not stop. These conditions may cause you to lose too much water and may lead to low blood pressure. You can also lose water by sweating, so drink plenty of water during exercise or in hot weather.
Check with your doctor right away if you have bloody urine, a decrease in frequency or amount of urine, an increase in blood pressure, increased thirst, loss of appetite, lower back or side pain, nausea, swelling of the face, fingers, or lower legs, trouble breathing, unusual tiredness or weakness, vomiting, or weight gain. These could be symptoms of a serious kidney problem.
Check with your doctor immediately if blurred vision, difficulty reading, eye pain, or any other change in vision occurs during or after treatment. This could be a sign of a serious eye problem. Your doctor may want an eye doctor to check your eyes.
This medicine may affect blood sugar levels. Diabetic patients may notice a change in the results of blood or urine glucose tests. Talk to your doctor if you have any questions.
Ask your doctor before you use medicines, supplements, or salt substitutes that contain potassium.
Drinking alcohol or taking narcotic pain relievers or sleeping pills with this medicine may intensify feeling lightheaded, dizzy, or faint. Tell your doctor if you are drinking alcohol or using pain relievers or sleeping pills.
This medicine may increase your risk of getting skin cancer (eg, non-melanoma skin cancer). Avoid sun exposure. Use a sunscreen when you are outdoors. Avoid sunlamps and tanning beds. Talk to your doctor if you have concerns about this risk.
Do not take other medicines unless they have been discussed with your doctor. This especially includes prescription or nonprescription (over-the-counter [OTC]) medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems, and herbal or vitamin supplements.
Side Effects of losartan and hydrochlorothiazide
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
- cough
- dark-colored urine
- decreased frequency of urine
- decreased urine output
- diarrhea
- difficulty swallowing
- dizziness
- dry mouth
- fast, irregular, pounding, or racing heartbeat or pulse
- fever
- hives, itching skin, rash
- 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
- sore throat
- 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
- weight gain
- 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:
More common
- Body aches or pain
- headache
- loss of voice
- sneezing
- sore throat
- stuffy or runny nose
Rare
- Dry cough
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
- heartburn
- inability to have or keep an erection
- indigestion
- loss in sexual ability, desire, drive, or performance
- trouble sleeping
- weight loss
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.
Commonly used brand name(s)
In the U.S.
- Hyzaar
Available Dosage Forms:
- Tablet
Therapeutic Class: Angiotensin II Receptor Antagonist/Thiazide Combination
Pharmacologic Class: Losartan
Chemical Class: Thiazide
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