Valsartan and Hydrochlorothiazide (Oral)

Known in the US as Diovan HCT, valsartan and hydrochlorothiazide is a drug designed to treat hypertension which works by both relaxing narrow blood vessels and reducing fluid retention.


Valsartan and hydrochlorothiazide, US brand name Diovan HCT, is a medicine used to treat high blood pressure. Sometimes it is used in combination with other medications to reduce blood pressure, but it can also be used alone.

How does valsartan and hydrochlorothiazide work?

High blood pressure forces the heart to work much harder than usual to deliver blood throughout the body, and over time this can damage the heart and arteries. It also makes it harder for the body to receive adequate amounts of oxygen. By reducing blood pressure, the heart is able to continue to work at a normal rate and is less likely to become damaged. The rest of the body will also become healthier due to the increased flow of oxygen-rich blood.

Valsartan is an angiotensin II receptor blocker, also known as an ARB. It works by blocking a hormone called angiotensin II, which has two effects on the body. Firstly, it causes blood vessels to constrict and become narrower, which increases blood pressure. Secondly, it triggers the production of a hormone that causes the body to retain water, and this extra fluid can also contribute to high blood pressure. By blocking angiotensin II, valsartan successfully widens blood vessels and relieves fluid retention to reduce blood pressure to healthy levels.

Hydrochlorothiazide is a thiazide diuretic, also known as a water pill. These types of medications work to flush salt out of the body, something which causes fluid retention. People who take thiazide diuretics often find that they need to urinate more frequently, since the body flushes both salt and water out of the body at an increased rate. Many people find that hydrochlorothiazide is most effective when they also minimize their salt intake.

By combining both valsartan and hydrochlorothiazide into one medicine, hypertension can be tackled in two ways, which often makes for a more successful treatment than using the medicines alone.

Who can use valsartan and hydrochlorothiazide?

Valsatran and hydrochlorothiazide might be given to a wide variety of people with high blood pressure. It can help to reduce the risk of heart attack, stroke, heart failure and kidney failure, all of which are possible consequences of high blood pressure. Often, it's given to people who have experienced unpleasant side effects after using ACE (angiotensin-converting-enzyme) inhibitors in an attempt to reduce high blood pressure.

ARBs such as Valsatran and hydrochlorothiazide can be particularly useful for individuals who have diabetes or kidney disease, as well as hypertension. This is because the medicine helps to flush salt and fluid from the body which can help to protect the kidneys from additional damage.

What other treatment is recommended with valsartan and hydrochlorothiazide?

High blood pressure often occurs as a result of lifestyle factors, such as being overweight or eating an unbalanced diet. Doctors may recommend adjusting certain lifestyle factors to help control high blood pressure alongside medicine. They may recommend the following:

  • Losing weight
  • Reducing salt intake
  • Reducing cholesterol intake
  • Reducing intake of trans fats
  • Increasing exercise

Adopting a new diet or exercise regime can put a lot of pressure on the body, even if it is designed to improve the health of the body in the long term. Always discuss such dramatic lifestyle changes with your doctor first. When it comes to exercise, ask your doctor what types of activity are safest for you, considering your high blood pressure and other health problems you may suffer from. It is usually recommended to begin at a low rate of physical activity and gradually increase the frequency and intensity of exercise as your body becomes fitter.

Condition(s) treated

  • High blood pressure (hypertension)

Type of medicine

  • Angiotensin II receptor blocker (ARB), thiazide diuretic

Side Effects

There are a variety of potential side effects of valsartan and hydrochlorothiazide, some of which require no medical attention, while others should always be reported to a doctor.

One of the most common side effects of valsartan and hydrochlorothiazide is an increased need to urinate. Since the drug is a thiazide diuretic designed to alleviate fluid retention, this is nothing to worry about and may only pose a slight inconvenience to the patient.

The following side effects are reasonably common, but not ones which require medical attention:

  • Headache
  • Mild diarrhea
  • Cough

The following are rare side effects which also do not require medical attention:

  • Sunlight sensitivity
  • Increased rate of sweating
  • Redness of skin on the face and neck
  • Reduction in sex drive or sexual performance
  • Anxiety

Some people who take valsartan and hydrochlorothiazide also experience increased hair loss or thinning of the hair. The frequency at which this side effect occurs is unknown, but it is not something that requires medical attention.

The side effects listed above may dissipate over time as the body adjusts to the treatment, but if they continue and cause you significant discomfort, consult your doctor. They may be able to recommend lifestyle adjustments which could prevent or reduce the side effects. If this is not possible, it may be necessary to find an alternative medicine or medicine combination.

The following side effects, although reasonably uncommon, may occur with the use of valsartan and hydrochlorothiazide and should be reported to a doctor immediately.

  • Difficulty swallowing
  • Cold or flu-like symptoms
  • Sore throat
  • Swollen or tender lymph nodes (glands) in the neck
  • Body weakness or unusual fatigue

The following side effects are very rare, but should be reported to a doctor immediately:

  • Stomach pain or bloating
  • Blurred vision, eye pain, watering of eyes or itching, swelling or redness of the eye or eyelid
  • Fever or chills
  • Fainting
  • Flushing of the skin throughout the body
  • Sudden swelling or stiffness in the joints
  • Nausea
  • Rash or hives on the skin
  • Difficulty breathing or wheezing when breathing
  • Vomiting
  • Yellow skin or eyes

The following side effects, which should be reported to a doctor immediately, occur at a frequency that is unknown:

  • Confusion or nervousness
  • Seizures or muscle cramps or spasms
  • Stiffness or pain in muscles
  • Heaviness or weakness in legs
  • Tingling or numbness in lips, hands or feet
  • Decreased urine output or very dark urine
  • Dizziness or lightheadedness
  • Drowsiness
  • Dry mouth or increased thirst
  • Fast heartbeat or irregular heartbeat
  • Large swellings on face, eyelids, mouth, throat, hands, feet, legs or genitals
  • Light-colored stools


Valsartan and hydrochlorothiazide is administered in tablet form. It is not necessary to take the drug with water, but it may be helpful. The medicine can be taken both with or without food.

Dosage of Diovan HCT varies from one patient to the next, but most adults begin with 320 mg valsartan and 25mg hydrochlorothiazide. Both medicines are combined into one pill (Diovan HCT) which is usually taken once each day. Doctors may adjust this dosage depending on the severity of your condition, other health conditions you suffer from and other medications you currently take.

Sometimes children are prescribed valsartan and hydrochlorothiazide, but in these instances, the dosage is always determined by the doctor on a case-by-case basis.

If a dose of valsartan and hydrochlorothiazide is missed, take the medication as soon as you remember. If, when you realize you have missed a dose it is almost time for the next one, simply skip the missed dose and continue to take the medication as normal from then on out. Do not double up doses of valsartan and hydrochlorothiazide if you have missed one.

Always follow the recommendations given to you by your doctor. It's also very important to follow advice on the frequency of doses, the time of day they are taken and the length of time in between doses. Do not stop taking valsartan and hydrochlorothiazide unless your doctor recommends it. This medication is designed for long-term use, and even if your blood pressure returns to a healthy level you should continue to take it. Stopping the use of valsartan and hydrochlorothiazide could cause further health complications.


It is not recommended that Diovan HCT is taken with the following medications:

  • Aliskiren (a direct renin inhibitor used to treat essential hypertension)
  • Dofetilide (an anti-arrhythmic drug used to treat irregular heartbeat)

If you are taking either of these medications, your doctor will either choose not to prescribe you Diovan HCT, or they may change your existing medications for alternative treatments.

The following medications may interact with Diovan HCT and cause side effects:

  • Aceclofenac
  • Acemetacin
  • Acetyldigoxin
  • Amphetamine
  • Amtolmetin Guacil
  • Arsenic Trioxide
  • Aspirin
  • Benazepril
  • Bromfenac
  • Bufexamac
  • Captopril
  • Celecoxib
  • Choline Salicylate
  • Clonixin
  • Cyclophosphamide
  • Deslanoside
  • Dexibuprofen
  • Dexketoprofen
  • Diclofenac
  • Diflunisal
  • Digitalis
  • Digitoxin
  • Digoxin
  • Dipyrone
  • Droperidol
  • Droxicam
  • Enalapril
  • Enalaprilat
  • Etodolac
  • Etofenamate
  • Etoricoxib
  • Felbinac
  • Fenoprofen
  • Fepradinol
  • Feprazone
  • Flecainide
  • Floctafenine
  • Flufenamic Acid
  • Flurbiprofen
  • Fosinopril
  • Ibuprofen
  • Indomethacin
  • Ketanserin
  • Ketoprofen
  • Ketorolac
  • Levomethadyl
  • Lisinopril
  • Lithium
  • Lornoxicam
  • Loxoprofen
  • Lumiracoxib
  • Meclofenamate
  • Mefenamic Acid
  • Meloxicam
  • Methotrexate
  • Metildigoxin
  • Moexipril
  • Morniflumate
  • Nabumetone
  • Naproxen
  • Nepafenac
  • Niflumic Acid
  • Nimesulide
  • Nimesulide Beta Cyclodextrin
  • Ouabain
  • Oxaprozin
  • Oxyphenbutazone
  • Parecoxib
  • Perindopril
  • Phenylbutazone
  • Piketoprofen
  • Piroxicam
  • Proglumetacin
  • Propyphenazone
  • Proquazone
  • Proscillaridin
  • Quinapril
  • Ramipril
  • Rofecoxib
  • Salicylic Acid
  • Salsalate
  • Simeprevir
  • Sodium Salicylate
  • Sotalol
  • Sulindac
  • Tenoxicam
  • Tiaprofenic Acid
  • Tolfenamic Acid
  • Tolmetin
  • Trandolapril
  • Trimethoprim
  • Valdecoxib

If you are already taking any of these medications, your doctor may adjust the dosages of your medicines or change the frequency at which you take some medicines. It's vital that your doctor is aware of all medications you currently take when considering the prescription of Diovan HCT.


Some people may be at an increased risk of side effects or of an allergic reaction to valsartan and hydrochlorothiazide if they have other medical conditions. If you suffer from the following conditions, be sure to let your doctor know:

  • Anuria (inability to produce urine)
  • Asthma
  • Diabetes if also taking aliskiren
  • Electrolyte imbalances such as high or low sodium, calcium, magnesium or potassium
  • Fluid imbalances
  • Gallstones
  • Glaucoma
  • Gout
  • Hypercholestorolemia (high cholesterol levels)
  • Hypertriglyceridemia (high fat levels in blood)
  • Lupus (an autoimmune disorder)
  • Myopia (vision problem)
  • Previous allergic reaction to other blood pressure medicines
  • revious allergy to sulfa drug
  • Severe congestive heart failure
  • Severe kidney disease

Pregnancy and valsartan and hydrochlorothiazide

Diovan HCT is not recommended for pregnant women during any stage of pregnancy. Studies have proven that the drug poses a risk to the fetus. However, in very life-threatening situations, the benefits of the drug may be greater than the potential risk to the fetus. In these instances, doctors may prescribe Diovan HCT if other medicines or medicine combinations are not suitable for alleviating high blood pressure.

Little research has been performed on the effects of valsartan and hydrochlorothiazide on infants when taken by breastfeeding mothers. For this reason, it is generally not recommended for women who are nursing. Doctors may prefer to use alternative medicines or treatments where possible. It is recommended that new mothers make their doctor aware that they are breastfeeding when discussing treatment options for high blood pressure.

Lifestyle factors to consider when taking valsartan and hydrochlorothiazide

People with diabetes may find that valsartan and hydrochlorothiazide affects their blood sugar levels. When you first begin taking the drug, check your blood sugar levels regularly and report any irregularities to your doctor. If it does seem to affect blood sugar, your doctor may adjust the dosage, your diet or your diabetes medication.

Since valsartan and hydrochlorothiazide can cause dizziness, it's recommended that you do not operate machinery, drive a vehicle or do any other activity which requires concentration and alertness until you can be sure how the medicine affects you. Take care when consuming alcohol too, as this may worsen dizziness; you may have to limit alcohol intake or stop drinking alcohol completely.

Valsartan and hydrochlorothiazide tends to cause an increase in urination. Drink plenty of fluids to maintain healthy hydration, particularly if the drug has also caused diarrhea. If diarrhea is severe and prolonged, visit your doctor immediately.


Valsartan and hydrochlorothiazide should be kept in a room temperature environment, away from direct light, heat or moisture. It should be stored in a closed container and out of reach of children. Always retain the information leaflet provided with the medicine for future reference.

Outdated medicine should never be consumed. If you have valsartan and hydrochlorothiazide tablets that you no longer require, consult your healthcare professional on how to dispose of them correctly. Do not toss unused medication into the trash.


Valsartan and hydrochlorothiazide is prescribed to reduce high blood pressure (hypertension). It works in two ways. Firstly, valsartan works to block a hormone called angiotensin II which constricts and narrows blood vessels. Secondly, hydrochlorothiazide works to flush salt and fluid from the body, which further reduces the constriction of blood vessels. When combined, these medicines are more effective in treating hypertension than when used alone.

Adults are most commonly prescribed valsartan and hydrochlorothiazide, but in rare instances children may be prescribed it too. It is not recommended that valsartan and hydrochlorothiazide is used by pregnant women, as it poses a risk to the fetus during each trimester of pregnancy. However, in life-threatening instances, the benefits of the drug may outweigh the potential risks to the fetus.

Valsartan and hydrochlorothiazide should never be taken with aliskiren or dofetilide. Individuals who take these medications should notify their doctor when discussing treatment options for hypertension. Other medications or treatments will be considered instead.

There are a range of side effects associated with valsartan and hydrochlorothiazide use, many of which do not require medical attention. Since the drug is a diuretic it increases the rate of urination, and this tends to be the most common side effect. Patients may also notice headaches, a cough, mild diarrhea, increased sweating, sensitivity to sunlight, and a reduction in sexual performance. Often, these side effects dissipate as the body adjusts to the medication. If they become an ongoing problem, it may be possible to adjust the dosage or some lifestyle factors to reduce or prevent them.

Some side effects, although rare, are serious and should be reported to a doctor immediately. This includes pain in the eyes, joints or muscles, difficulty swallowing or breathing, sore throat, swollen glands or other cold or flu-like symptoms, vomiting or severe diarrhea, reduce urination or dark urine, rash or hives on the skin, yellowing of the skin or eyes, and dry mouth or increased thirst.

Valsartan and hydrochlorothiazide tends to be most effective when patients adopt other positive lifestyle changes to reduce their blood pressure. It may be helpful to lose weight, consume less salt, adopt a more balanced diet and take additional exercise. However, patients should always consult their doctor when adopting significant changes to their lifestyle.

Last Reviewed:
December 23, 2017
Last Updated:
April 05, 2018
Content Source: