How does this medication work? What will it do for me?
This is a combination product that contains two medications used to lower hypertension (high blood pressure): telmisartan and hydrochlorothiazide. It is used to treat high blood pressure for people who require treatment with both telmisartan and hydrochlorothiazide.
Telmisartan belongs to a class of medications called angiotensin II blockers, which help to lower blood pressure by relaxing blood vessels. Hydrochlorothiazide is a diuretic (water pill) that helps control blood pressure by getting rid of excess salt and water.
This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.
Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.
What form(s) does this medication come in?
CO Telmisartan/HCT is no longer being manufactured for sale in Canada. For brands that may still be available, search under telmisartan – hydrochlorothiazide. This article is being kept available for reference purposes only. If you are using this medication, speak with your doctor or pharmacist for information about your treatment options.
How should I use this medication?
The recommended dose is 1 tablet once daily. This medication is intended to be used by people who have not had their blood pressure well-controlled with just telmisartan, or by people who have had doses of telmisartan and hydrochlorothiazide already established.
The medication can be taken with or without food, but it should be taken the same way every time (i.e., always with food or always without food).
Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.
It is important that this medication be taken exactly as prescribed by your doctor. If you miss a dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.
Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children. It should be left in the protective blisters until immediately before you take it.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
Who should NOT take this medication?
Do not take telmisartan - hydrochlorothiazide if you:
- are allergic to telmisartan, hydrochlorothiazide, or any ingredients of the medication
- are allergic to sulfa (sulfonamide) medications (e.g., sulfamethoxazole)
- are pregnant or breast-feeding
- have anuria (able to pass little or no urine)
- have diabetes or kidney disease and are taking aliskiren
- have fructose intolerance (a rare hereditary condition)
- have galactose intolerance (a rare hereditary condition)
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 or leg pain
- cold-like symptoms (e.g., runny or stuffy nose, sore throat, headache)
- decreased appetite
- dizziness or lightheadedness when rising from a lying or sitting position
- dry mouth
- flu-like symptoms
- joint or muscle pain
- muscle spasms
- pins and needles sensation
- sexual difficulties
- skin rash
- swollen glands (in mouth)
- trouble sleeping
Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- pounding, rapid heartbeat
- signs of anemia (low red blood cells; e.g., dizziness, pale skin, unusual tiredness or weakness, shortness of breath)
- signs of bleeding (e.g., unusual nosebleeds, bruising, blood in urine, coughing blood, bleeding gums, cuts that don't stop bleeding)
- signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
- signs of electrolyte changes (e.g., confusion, drowsiness, dry mouth, muscle fatigue, nausea, thirst, weakness)
- signs of gout (e.g., joint pain, swelling and warmth of joints)
- signs of infections (symptoms may include fever or chills, severe diarrhea, shortness of breath, prolonged dizziness, headache, stiff neck, weight loss, or listlessness)
- signs of kidney problems (e.g., decreased urination, nausea, vomiting, swelling of the feet and ankles)
- signs of liver damage (yellowing of skin or whites of eyes, abdominal pain, loss of appetite, brown urine, light-coloured stools, tiredness, or weakness)
- signs of non-melanoma skin cancer (e.g., lump or discoloured patch on skin, pink/red firm lumps, or flat and scaly patches)
- signs of pancreatitis (e.g., abdominal pain on the upper left side, back pain, nausea, fever, chills, rapid heartbeat, swollen abdomen)
- swelling legs, ankles, or hands
- symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
- symptoms of low blood sugar (e.g., cold sweat, cool pale skin, headache, fast heartbeat, weakness)
- symptoms of a urinary tract infection (e.g., pain when urinating, urinating more often than usual, low back or flank pain)
- unexplained muscle tenderness or weakness
- vision changes, blurred vision, or eye pain
Stop taking the medication and seek immediate medical attention if any of the following occur:
- chest pain
- severe skin rash, including skin blistering and peeling (possibly with headache, fever, coughing, or aching before the rash begins)
- signs of a serious allergic reaction (e.g., swelling of face or throat, hives, difficulty breathing)
- symptoms of sepsis (blood poisoning; e.g., confusion, chills, fever or low body temperature, shakiness, irregular heartbeat)
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.
Allergic reaction: Some people who are allergic to sulfonamide medications also experience allergic reactions to hydrochlorothiazide. Before you take this medication, tell your doctor about any previous reactions you have had to medications, especially to sulfonamide antibiotics or diabetes medications. Contact your doctor at once if you experience signs of an allergic reaction, such as skin rash, itching, difficulty breathing, or swelling of the face and throat.
Angioedema: This medication may cause a serious allergic reaction called angioedema, which may be fatal if not treated promptly. If you have difficulty breathing or notice hives or swelling of the face, lips, tongue, or throat, stop taking this medication and get emergency medical help immediately. Other angiotensin II receptor antagonists should not be taken in the future. People who have had angioedema caused by other substances may be at increased risk of angioedema while taking this medication.
Cholesterol: Cholesterol and triglyceride levels may increase when taking hydrochlorothiazide. If you have increased cholesterol or triglyceride levels, 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.
Diabetes: Hydrochlorothiazide may make it more difficult for people with diabetes to control their blood sugar levels. High blood sugar may occur, glucose tolerance may change, and diabetes may worsen. A dose adjustment of diabetes medications, including insulin, may be required. If you have diabetes, 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.
Electrolytes: The use of hydrochlorothiazide can reduce the levels of electrolytes such as potassium, sodium, magnesium, and chloride and increase the levels of calcium. Your doctor will periodically check to see if these levels are in balance, and a potassium supplement may be recommended. Warning signs or symptoms of fluid and electrolyte imbalance include:
- dryness of mouth
- low blood pressure
- muscle pains or cramps
- muscular fatigue
- nausea and vomiting
- racing heartbeat
Hereditary fructose or galactose intolerance: Due to the sorbitol and lactose content in the medication, this medication is not suitable for people with hereditary fructose or galactose intolerance.
Gout: An acute gout attack may occur in some patients taking telmisartan - hydrochlorothiazide as a result of high levels of uric acid in the blood. Symptoms of an acute gout attack include sudden pain, swelling, and stiffness in the affected joint, often the big toe. You may also experience a fever. If this is your first attack, seek medical attention as soon as possible. If you have had gout attacks before, follow your doctor's instructions for dealing with the attack.
Kidney function: Telmisartan - hydrochlorothiazide can cause changes to kidney function that may result in decreased kidney function, kidney failure, or possibly death. Certain people have experienced changes in kidney function (e.g., people with narrowed blood vessels in their kidneys, or those with severe congestive heart failure). The use of diuretics (water pills), nonsteroidal anti-inflammatory drugs (NSAIDs), or aliskiren may further increase risk of kidney problems for people already at risk for this problem. If you have reduced kidney function, renal artery stenosis (narrowing of blood vessels in the kidneys), or congestive heart failure, 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. If you have reduced kidney function, you may require lower doses of this medication.
Liver function: Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have reduced liver function or liver disease, 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.
This medication may also cause a decrease in liver function. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately.
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) or the medication aliskiren, have reduced salt intake, are on dialysis, or are experiencing diarrhea or vomiting. Blood pressure should be monitored more often in these situations. To reduce the risk of dizziness, people with low blood pressure or who are 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.
Excessive sweating and lack of fluid intake may lead to an extreme drop in blood pressure because of reduced fluid in your blood vessels. Vomiting or diarrhea may also lead to a drop in blood pressure. Consult your doctor if you feel your blood pressure is too low.
Lupus: There have been reports of a worsening or activation of lupus in people taking hydrochlorothiazide. If you have lupus or a history of lupus, 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.
Sensitivity to sunlight: This medication may increase the sensitivity of the skin to sunlight, increasing the risk of sunburn. Avoid exposure to sunlight for long periods of time, particularly between the hours of 10 am and 2 pm, while you are taking this medication. Wear a broad-spectrum sunscreen with an SPF of 30 or higher. If you notice any unusual skin rash or peeling, contact your doctor immediately.
Skin cancer: Recent studies of hydrochlorothiazide have suggested that long-term use of hydrochlorothiazide may be associated with an increased risk of developing non-melanoma skin cancer. Regularly check your skin for new moles or lesions or changes to any existing ones and let your doctor know if you have any concerns.
Vision changes: Hydrochlorothiazide occasionally causes vision changes, including increased eye pressure and myopia (nearsightedness). If you experience any eye symptoms, such as pain or change in vision, contact your doctor as soon as possible.
Pregnancy: Telmisartan can cause injury or death to the developing fetus if taken by a woman who is pregnant. This medication should not be taken by pregnant women. If you become pregnant while taking telmisartan - hydrochlorothiazide, consult your doctor immediately as the medication should be stopped as soon as possible.
Breast-feeding: It is not known if telmisartan passes into breast milk. Hydrochlorothiazide does pass into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children and is not recommended.
Seniors: Seniors may be more sensitive to the side effects of this medication.
What other drugs could interact with this medication?
There may be an interaction between telmisartan - hydrochlorothiazide and any of the following:
- alpha-agonists (e.g., clonidine, methyldopa)
- alpha-adrenergic blocking agents (e.g., alfuzosin, doxazosin, prazosin, terazosin)
- amphetamines (e.g., dextroamphetamine, lisdexamfetamine)
- angiotensin-converting enzyme inhibitors (ACEIs; captopril, enalapril, ramipril)
- other angiotensin receptor blockers (ARBs; e.g., candesartan, irbesartan, losartan)
- antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
- antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
- barbiturates (e.g., butalbital, pentobarbital, phenobarbital)
- beta-blockers (e.g., atenolol, carvedilol, propranolol)
- beta-2 agonists (e.g., salbutamol, formoterol, terbutaline)
- calcium carbonate, calcium citrate
- calcium channel blockers (e.g., amlodipine, diltiazem, nifedipine, verapamil)
- colestipol resins
- oral corticosteroids (e.g., dexamethasone, hydrocortisone, prednisone)
- diabetes medications (e.g., canagliflozin, glyburide, insulin, linagliptin, liraglutide, metformin, rosiglitazone)
- diuretics (water pills; e.g., furosemide, hydrochlorothiazide, triamterene)
- iron sucrose
- low-molecular-weight heparins (e.g., dalteparin, enoxaparin, tinzaparin)
- medications that increase blood levels of potassium (e.g., potassium chloride, salt substitutes containing potassium)
- monoamine oxidase inhibitors (MAOIs; e.g., moclobemide, phenelzine, rasagiline, selegiline, tranylcypromine)
- muscle relaxants (e.g., baclofen, cyclobenzaprine, orphenadrine, tizanidine)
- narcotic pain relievers (e.g., codeine, fentanyl, morphine)
- nitrates (e.g., nitroglycerin, isosorbide dinitrate, isosorbide mononitrate)
- nonsteroidal anti-inflammatory drugs (NSAIDs; e.g., ibuprofen, naproxen)
- phosphodiesterase-5 inhibitors (e.g., sildenafil, tadalafil, vardenafil)
- selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, fluoxetine, paroxetine, sertraline)
- sodium phosphates
- sulfonamide antibiotics ("sulfas"; sulfadiazine, sulfamethoxazole)
- tricyclic antidepressants (e.g., amitriptyline, clomipramine, desipramine, trimipramine)
- vitamin D analogues (e.g., alfacalcidol, calcitriol, cholecalciferol)
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 that 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.
All material copyright MediResource Inc. 1996 – 2023. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/CO-TelmisartanHCT