olmesartan - hydrochlorothiazide
In this drug factsheet:
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- abdominal pain
- back pain
- upper respiratory tract infection (such as colds or sinus infections)
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- changes to hearing
- fainting or severe dizziness
- flu-like illness (e.g., runny nose, sore throat, cough)
- dark coloured or brown urine
- joint pain
- muscle pain
- signs of bronchitis (e.g., high fever, cough, shortness of breath, weakness, fatigue)
- signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
Stop taking the medication and seek immediate medical attention if any of the following occur:
- signs of a serious allergic reaction (swelling of face, lips, tongue, or throat; hives; difficulty breathing)
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Cholesterol: Cholesterol and triglyceride levels may increase when taking hydrochlorothiazide. Your doctor may want you to have regular blood tests to monitor your cholesterol levels while you are taking this medication.
Diabetes: Hydrochlorothiazide may make it more difficult for people with diabetes to control their blood sugar levels. The dose of your antidiabetes medications, including insulin, may need to be adjusted. Your doctor may ask you to test your blood sugar levels more frequently when you are taking this medication.
Drowsiness/reduced alertness: Blood pressure medications may cause drowsiness or dizziness. Avoid driving or operating machinery until you know whether the medication affects you in this way.
Fluid and electrolyte balance: Your levels of electrolytes such as potassium, sodium, magnesium, chloride, and calcium may change due to the hydrochlorothiazide in this medication. If you experience symptoms of fluid and electrolyte imbalance such as muscle pains or cramps; dry mouth; numb hands, feet, or lips; or racing heartbeat, contact your doctor as soon as possible. Your doctor may want you to have regular blood tests to monitor these levels while you are taking this medication.
Gout: This medication may cause high levels of uric acid in the blood or cause gout. If you have gout, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Kidney function: This medication may affect kidney function, especially for people who already have kidney problems. If you have reduced kidney function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. This medication should not be taken by people with severely impaired kidney function.
Liver function: People with reduced liver function may need a lower-than-usual dose of olmesartan; therefore, it may be necessary to use the components of the combination product separately. If you have reduced liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. This medication is not recommended for people with severe liver impairment.
Low blood pressure: Occasionally, a greater-than-expected drop in blood pressure occurs after taking this medication. It is more likely to occur if you are taking additional diuretics (water pills), have reduced salt intake, are on dialysis, have diarrhea, or are vomiting. Blood pressure should be monitored more often in these situations. To reduce the risk of dizziness, people with low blood pressure or those just starting to take this medication should stand or sit up slowly when getting up from a lying down or sitting position. If low blood pressure causes you to faint or feel lightheaded, contact your doctor.
Lupus: There have been reports of a worsening or activation of lupus in people taking hydrochlorothiazide. Talk to your doctor if you have any concerns.
Pregnancy: This medication may cause harm to an unborn baby and should not be used during pregnancy. If you become pregnant while taking this medication, stop taking the medication and contact your doctor immediately.
Breast-feeding: It is not known if olmesartan passes into breast milk. Hydrochlorothiazide does pass into breast milk. If you are a breast-feeding mother and are taking olmesartan - hydrochlorothiazide, it may affect your baby. Do not breast-feed while you are taking this medication.
Children: The safety and effectiveness of using this medication have not been established for children. This medication is not recommended for children.
What other drugs could interact with this medication?
There may be an interaction between olmesartan - hydrochlorothiazide and any of the following:
- ACTH (adrenocorticotropic hormone)
- antidiabetes medications (e.g., insulin, glyburide)
- barbiturates (e.g., phenobarbital)
- colestipol resins
- corticosteroids (e.g., cortisone, prednisone)
- medications that increase potassium levels (such as potassium supplements, spironolactone, triamterene, amiloride, or salt substitutes containing potassium)
- narcotic medications (e.g., morphine, codeine)
- nonsteroidal anti-inflammatory drugs (NSAIDs; e.g., ibuprofen, indomethacin, naproxen)
- other diuretics (e.g., furosemide)
- other medications that lower blood pressure
- sympathomimetics (e.g., phenylephrine, xylometazoline) which may be found in decongestants, cold and allergy medications
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.