Olmesartan and hydrochlorothiazide (Oral)
Medically reviewed by Drugs.com. Last updated on Dec 3, 2022.
Drugs that act directly on the renin-angiotensin system can cause injury or death to the developing fetus when used during pregnancy. Stop therapy as soon as possible if pregnancy is detected .
Commonly used brand name(s)
In the U.S.
- Benicar HCT
Available Dosage Forms:
Therapeutic Class: Angiotensin II Receptor Antagonist/Thiazide Combination
Pharmacologic Class: Angiotensin II Receptor Antagonist
Chemical Class: Thiazide
Uses for olmesartan and hydrochlorothiazide
Olmesartan 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 can reduce the risk of strokes and heart attacks.
Olmesartan is an angiotensin II receptor blocker (ARB). It works by blocking a substance in the body that causes blood vessels to tighten. As a result, olmesartan relaxes the blood vessels. This lowers blood pressure and increases 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.
Olmesartan and hydrochlorothiazide is available only with your doctor's prescription.
Before using olmesartan 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 olmesartan and hydrochlorothiazide, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to olmesartan and hydrochlorothiazide 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.
Appropriate studies have not been performed on the relationship of age to the effects of olmesartan and hydrochlorothiazide combination in the pediatric population. Safety and efficacy have not been established.
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of olmesartan and hydrochlorothiazide combination in the elderly. However, elderly patients are more likely to have age-related kidney, liver, or heart problems, which may require caution and an adjustment in the dose for patients receiving olmesartan and hydrochlorothiazide combination.
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 olmesartan and hydrochlorothiazide, 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 olmesartan and hydrochlorothiazide 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 olmesartan and hydrochlorothiazide 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.
- Amtolmetin Guacil
- Arsenic Trioxide
- Choline Salicylate
- Flufenamic Acid
- Mefenamic Acid
- Niflumic Acid
- Nimesulide Beta Cyclodextrin
- Salicylic Acid
- Sodium Salicylate
- Tiaprofenic Acid
- Tolfenamic Acid
Using olmesartan and hydrochlorothiazide 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.
- Aminolevulinic Acid
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. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of olmesartan and hydrochlorothiazide. Make sure you tell your doctor if you have any other medical problems, especially:
- Angle-closure glaucoma or
- Diabetes or
- Gout or
- Hypercalcemia (high calcium in the blood) or
- Hyperlipidemia (high cholesterol in the blood) or
- Hyperuricemia (high uric acid in the blood) or
- Hypokalemia (low potassium in the blood) or
- Hypomagnesemia (low magnesium in the blood) or
- Liver disease or
- Myopia (nearsighted; can't see objects at a distance) or
- Systemic lupus erythematosus (immune system disease)—Use with caution. May make these conditions worse.
- Asthma, or history of or
- Congestive heart failure, severe or
- Dehydration, severe or
- Hyponatremia (low sodium in the blood) or
- Penicillin allergy, history of or
- Sulfa drug allergy, history of—Use with caution. May cause side effects to become worse.
- Kidney disease—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
Proper use of olmesartan and hydrochlorothiazide
Take olmesartan and hydrochlorothiazide only as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered.
Take olmesartan and hydrochlorothiazide with or without food.
If you are also using colesevelam (Welchol®), take it at least 4 hours after taking Benicar HCT®.
The dose of olmesartan and hydrochlorothiazide 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 olmesartan and hydrochlorothiazide. 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—One tablet once a day. Your doctor may adjust your dose if needed.
- Children—Use and dose must be determined by your doctor.
- For high blood pressure:
If you miss a dose of olmesartan and hydrochlorothiazide, 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.
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.
Precautions while using olmesartan and hydrochlorothiazide
It is very important that your doctor check your progress at regular visits to make sure olmesartan and hydrochlorothiazide is working properly. Blood and urine tests may be needed to check for unwanted effects.
Using olmesartan and hydrochlorothiazide while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using olmesartan and hydrochlorothiazide, tell your doctor right away.
Dizziness, lightheadedness, or fainting may also occur, especially when you get up suddenly from a lying or sitting position. Make sure you know how you react to the medicine before you drive, use machines, or do other things that could be dangerous if you are dizzy. If you feel dizzy, sit for a few moments before standing.
Check with your doctor right away if you become sick while taking olmesartan and hydrochlorothiazide, especially with severe or continuing nausea, vomiting, or diarrhea that does not stop. These conditions may cause you to lose too much water or salt and lead to low blood pressure. You can also lose water by sweating, so drink plenty of water during exercise or in hot weather.
Severe, chronic diarrhea with weight loss may develop months to years after taking olmesartan and hydrochlorothiazide. Tell your doctor right away if you have these symptoms.
Check with your doctor right away if blurred vision, difficulty with reading, eye pain, or any other vision change occurs with olmesartan and hydrochlorothiazide. This could be a sign of a serious eye problem. Your doctor may want an eye doctor to check your eyes.
Olmesartan and hydrochlorothiazide may affect blood sugar levels. Diabetic patients may notice a change in the results of blood or urine sugar tests. Talk to your doctor if you have any questions.
Do not take other medicines unless they have been discussed with your doctor. This 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.
Olmesartan and hydrochlorothiazide side effects
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:
- Bladder pain
- bloating or swelling of the face, arms, hands, lower legs, or feet
- bloody or cloudy urine
- blurred vision
- chest pain
- difficult, burning, or painful urination
- flushed, dry skin
- frequent urge to urinate
- fruit-like breath odor
- increased hunger
- increased urination
- joint pain, stiffness, or swelling
- lower back, side, or stomach pain
- rapid weight gain
- swelling of the feet or lower legs
- tingling of the hands or feet
- troubled breathing
- unexplained weight loss
- unusual weight gain or loss
- Swelling or puffiness of the face
Incidence not known
- decrease in amount of urine
- dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
- severe diarrhea with weight loss
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:
- Back pain
- body aches or pain
- difficulty with breathing
- ear congestion or pain
- head congestion
- hoarseness or other voice changes
- loss of voice
- runny or stuffy nose
- sore throat
- Acid or sour stomach
- difficulty with moving
- dizziness or lightheadedness
- feeling of constant movement of self or surroundings
- joint pain, stiffness, or swelling
- loss of appetite
- muscle pain or stiffness
- pain, swelling, or redness in the joints
- sensation of spinning
- stomach discomfort or upset
Incidence not known
- muscle pain or stiffness
- weakness or heaviness of the legs
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.
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