Micardis (Telmisartan)
Angiotensin II Receptor Blocker (ARB) for High Blood Pressure
Quick facts about Micardis (Telmisartan)
Key takeaways about Micardis
- Effective blood pressure control: Telmisartan has the longest half-life of any ARB (approximately 24 hours), providing consistent around-the-clock blood pressure lowering with once-daily dosing
- Cardiovascular protection: Proven to reduce the risk of heart attack, stroke, and cardiovascular death in high-risk patients, as demonstrated in the landmark ONTARGET trial
- Do not use during pregnancy: Micardis can cause serious harm to the unborn baby, particularly during the second and third trimesters, and must be discontinued immediately if pregnancy is confirmed
- Monitor potassium levels: Telmisartan can raise blood potassium levels, especially in patients with kidney disease or those taking potassium-sparing diuretics
- Full effect takes 4-8 weeks: While blood pressure begins to drop within hours, the maximum therapeutic benefit is usually achieved after 4 to 8 weeks of regular treatment
What Is Micardis and What Is It Used For?
Micardis (telmisartan) is an angiotensin II receptor blocker (ARB) prescribed to treat high blood pressure (hypertension) and to reduce the risk of cardiovascular events, including heart attack, stroke, and cardiovascular death, in adults who are at high risk. It works by blocking the hormone angiotensin II from tightening blood vessels, allowing them to relax and blood pressure to decrease.
Telmisartan belongs to a class of medicines known as angiotensin II receptor blockers, or ARBs. The renin-angiotensin-aldosterone system (RAAS) plays a central role in regulating blood pressure and fluid balance in the body. When the kidneys detect reduced blood flow, they release an enzyme called renin, which triggers a cascade resulting in the production of angiotensin II. This powerful hormone constricts blood vessels, stimulates aldosterone release (which causes the kidneys to retain sodium and water), and activates the sympathetic nervous system. Together, these actions increase blood pressure.
Telmisartan works by selectively blocking the angiotensin II type 1 (AT1) receptor. By preventing angiotensin II from binding to this receptor, telmisartan causes blood vessels to dilate, reduces aldosterone secretion, and lowers blood pressure. Unlike ACE inhibitors, which block the production of angiotensin II, ARBs like telmisartan block its action at the receptor level. This distinction is important because angiotensin II can be produced through alternative pathways that bypass ACE, meaning that ARBs may provide more complete blockade of the RAAS.
The primary indication for Micardis is the treatment of essential hypertension (high blood pressure) in adults. Hypertension is one of the most significant modifiable risk factors for cardiovascular disease worldwide, affecting an estimated 1.28 billion adults globally according to the World Health Organization. The European Society of Cardiology and European Society of Hypertension (ESC/ESH) 2023 guidelines recommend ARBs as one of the five main classes of first-line antihypertensive agents, alongside ACE inhibitors, calcium channel blockers, thiazide diuretics, and beta-blockers.
The second approved indication for Micardis is the reduction of cardiovascular morbidity in patients who are at high risk of cardiovascular events. This indication was established through the landmark ONTARGET (Ongoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial) study, published in the New England Journal of Medicine. This large randomized controlled trial involving over 25,000 patients demonstrated that telmisartan was non-inferior to the ACE inhibitor ramipril in preventing cardiovascular death, myocardial infarction, stroke, and hospitalization for heart failure.
When hypertension is left untreated, the persistently elevated pressure within the arteries causes progressive damage to vital organs over time. The heart must work harder to pump blood against the increased resistance, leading to left ventricular hypertrophy and eventually heart failure. The delicate blood vessels in the kidneys become damaged, leading to chronic kidney disease and potentially kidney failure. The arteries themselves develop atherosclerosis at an accelerated rate, increasing the risk of coronary artery disease and peripheral arterial disease. The blood vessels in the brain are also vulnerable, with uncontrolled hypertension being the single most important risk factor for both ischemic and hemorrhagic stroke. By effectively lowering blood pressure, Micardis helps to protect all of these target organs from damage.
What Should You Know Before Taking Micardis?
Before starting Micardis, your doctor needs to know about any kidney or liver disease, heart problems, diabetes, or if you are pregnant or planning to become pregnant. Micardis is strictly contraindicated during the last 6 months of pregnancy and must not be combined with aliskiren in patients with diabetes or moderate-to-severe kidney impairment.
As with all prescription medicines, it is essential that your prescribing physician has a complete picture of your medical history and current medications before you begin treatment with Micardis. Several conditions and situations require special caution or may preclude the use of this medicine entirely. The following sections outline the most important considerations that you and your healthcare provider should discuss.
Contraindications
There are certain situations in which Micardis must not be used. These absolute contraindications include:
- Hypersensitivity: If you are allergic to telmisartan or any of the other ingredients in Micardis, you must not take this medicine. Allergic reactions can range from mild skin rashes to severe anaphylaxis.
- Pregnancy (second and third trimesters): Micardis must not be used during the last 6 months of pregnancy, as it can cause serious harm to the developing fetus, including renal failure, oligohydramnios (reduced amniotic fluid), skull defects, and even fetal death.
- Severe hepatic impairment: Patients with severe liver disease, including biliary obstruction and cholestasis, should not take Micardis, as the drug is primarily eliminated through bile excretion.
- Concomitant use with aliskiren: The combination of Micardis with aliskiren (a direct renin inhibitor) is contraindicated in patients with diabetes mellitus or moderate-to-severe renal impairment (GFR less than 60 mL/min/1.73 m2), due to an increased risk of hyperkalemia, hypotension, and renal failure.
Warnings and Precautions
Special care is needed if any of the following conditions apply to you. In these cases, your doctor may need to adjust your dose, monitor you more closely, or consider alternative treatment:
- Renal artery stenosis: Patients with narrowing of the arteries supplying one or both kidneys are at increased risk of severe hypotension and renal impairment when treated with medicines that affect the RAAS, including Micardis.
- Kidney disease: If you have impaired kidney function, your doctor should monitor your kidney function and potassium levels regularly. In patients with severe renal impairment, there is limited clinical experience, and periodic monitoring of serum potassium and creatinine is recommended.
- Heart conditions: Patients with aortic or mitral valve stenosis, or hypertrophic obstructive cardiomyopathy, should use Micardis with caution. If you have heart failure, initiation of treatment may cause an excessive drop in blood pressure.
- Low blood pressure (hypotension): Symptomatic hypotension may occur, particularly after the first dose, in patients who are volume-depleted due to diuretic therapy, dietary salt restriction, diarrhea, or vomiting. Volume depletion should be corrected before starting Micardis.
- High potassium (hyperkalemia): ARBs, including telmisartan, can raise potassium levels. The risk is greater in patients with renal impairment, diabetes, or those also taking potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium.
- Diabetes: In patients with diabetes taking insulin or oral hypoglycemic agents, hypoglycemia may occur. Blood glucose monitoring may need to be intensified. Dose adjustments of the antidiabetic medication may be necessary.
- Primary aldosteronism: Patients with this condition generally do not respond well to medicines that work by blocking the RAAS, and therefore telmisartan is not recommended in these patients.
- Dual RAAS blockade: Combining Micardis with an ACE inhibitor or aliskiren is generally not recommended due to an increased risk of hypotension, hyperkalemia, and changes in kidney function compared with monotherapy.
Pregnancy and Breastfeeding
Micardis is not recommended during the first trimester of pregnancy and is strictly contraindicated during the second and third trimesters. If pregnancy is detected, Micardis should be discontinued as soon as possible. Medicines that act on the RAAS can reduce fetal kidney function, leading to reduced amniotic fluid (oligohydramnios), and can cause skull ossification defects. Potential neonatal adverse effects include renal failure, hypotension, and hyperkalemia.
It is not known whether telmisartan passes into human breast milk. Because of the potential risks to the nursing infant, the use of Micardis during breastfeeding is not recommended. Your doctor may advise you to use an alternative medicine that has a better-established safety profile during lactation, particularly in the weeks immediately following birth.
Do NOT take Micardis if you are pregnant, especially during the last 6 months. Telmisartan can cause serious birth defects and fetal harm, including kidney failure, reduced amniotic fluid, skull defects, and death. If you become pregnant while taking Micardis, stop the medication immediately and contact your doctor.
Children and Adolescents
Micardis is not recommended for use in children and adolescents under 18 years of age due to a lack of sufficient data on safety and efficacy in this age group. The European Medicines Agency (EMA) has waived the obligation for studies in certain subsets of the pediatric population. If a young patient requires antihypertensive treatment, the prescribing physician should select an agent with established pediatric safety data.
How Does Micardis Interact with Other Drugs?
Micardis can interact with several commonly used medicines, including lithium, potassium-raising agents, NSAIDs, ACE inhibitors, aliskiren, and digoxin. Some combinations can cause dangerously high potassium levels, kidney damage, or excessive blood pressure lowering. Always inform your doctor and pharmacist about all medicines you are taking.
Drug interactions are an important consideration with any medication, and Micardis is no exception. Because telmisartan works by blocking the renin-angiotensin-aldosterone system, it can interact with other drugs that affect blood pressure, kidney function, or electrolyte balance. Additionally, telmisartan has a unique pharmacokinetic profile. It is not significantly metabolized by the cytochrome P450 enzyme system, which reduces the likelihood of metabolic interactions, but it does undergo glucuronidation and is excreted primarily through the bile. Below is a detailed overview of the most clinically significant drug interactions.
| Drug / Class | Type | Effect | Recommendation |
|---|---|---|---|
| Lithium | Major | Reversible increases in lithium serum concentrations and toxicity | Monitor lithium levels closely if combination is necessary; avoid if possible |
| Potassium-raising agents (K+-sparing diuretics, supplements, salt substitutes) | Major | Increased risk of hyperkalemia, which can cause cardiac arrhythmias | Monitor serum potassium regularly; use with caution |
| ACE inhibitors (e.g., ramipril, enalapril) | Major | Dual RAAS blockade: increased risk of hypotension, hyperkalemia, and renal impairment | Avoid combination; if essential, close monitoring of renal function, potassium, and blood pressure |
| Aliskiren | Contraindicated (diabetes/renal impairment) | Increased risk of hyperkalemia, hypotension, and renal failure | Contraindicated in diabetic patients and those with GFR <60; avoid in all others |
| Diuretics (e.g., furosemide, hydrochlorothiazide) | Moderate | Additive blood pressure lowering; risk of symptomatic hypotension, especially first dose | Correct volume depletion before initiating telmisartan; consider lower starting dose |
| Digoxin | Moderate | Median increases of approximately 20% in digoxin peak and trough concentrations | Monitor digoxin levels when initiating, adjusting, or discontinuing telmisartan |
| NSAIDs (e.g., ibuprofen, diclofenac, celecoxib) | Moderate | May reduce the antihypertensive effect of telmisartan; increased risk of renal impairment and hyperkalemia | Monitor blood pressure, renal function, and potassium; use the lowest effective NSAID dose for the shortest duration |
| Corticosteroids (systemic) | Minor | May reduce the antihypertensive effect due to fluid and sodium retention | Monitor blood pressure; adjust antihypertensive dose if needed |
| Baclofen | Minor | May increase the blood pressure-lowering effect | Monitor blood pressure; adjust doses as needed |
Major Interactions
The most clinically significant interactions involve drugs that also affect the RAAS or potassium balance. Combining telmisartan with an ACE inhibitor (dual RAAS blockade) has been shown in large clinical trials, including ONTARGET, to increase the risk of hypotension, syncope, hyperkalemia, and renal dysfunction without providing additional cardiovascular benefit compared with monotherapy. For this reason, the European Medicines Agency and the ESC/ESH guidelines advise against routine dual RAAS blockade.
The interaction with lithium is particularly important because lithium has a narrow therapeutic index. Even small increases in lithium levels can cause toxicity, manifesting as tremor, nausea, diarrhea, and in severe cases, neurological and renal damage. If telmisartan must be used concurrently with lithium, serum lithium levels should be monitored frequently, particularly during initiation and dose adjustments.
Minor Interactions
Systemic corticosteroids can partially counteract the blood pressure-lowering effect of telmisartan through their tendency to cause sodium and water retention. Similarly, baclofen may enhance the hypotensive effect. While these interactions are generally of lesser clinical concern, patients should be aware of them and report any symptoms of low or high blood pressure to their healthcare provider. Regular blood pressure monitoring is advisable when these medicines are used together.
What Is the Correct Dosage of Micardis?
The usual starting dose of Micardis for hypertension is 40 mg once daily, which can be increased to 80 mg once daily for optimal blood pressure control. For cardiovascular risk reduction, the target dose is 80 mg once daily. Micardis should be taken at the same time each day, with or without food, and the tablet should be swallowed whole with water.
Correct dosing is essential for achieving optimal therapeutic results while minimizing the risk of side effects. The dose of Micardis depends on the indication, individual patient factors, and response to treatment. Your doctor will determine the most appropriate dose for you. The following information provides a general guide based on the approved prescribing information and international guidelines.
| Patient Group | Indication | Starting Dose | Usual Dose | Max Dose |
|---|---|---|---|---|
| Adults | Hypertension | 40 mg once daily | 40–80 mg once daily | 80 mg once daily |
| Adults | CV risk reduction | 80 mg once daily | 80 mg once daily | 80 mg once daily |
| Hepatic impairment (mild to moderate) | Hypertension | 20 mg once daily | 20–40 mg once daily | 40 mg once daily |
Adults
For the treatment of hypertension, the recommended starting dose is 40 mg taken once daily. Some patients may already benefit from a dose of 20 mg daily. In cases where the target blood pressure is not achieved after at least four weeks of treatment, the dose may be increased to a maximum of 80 mg once daily. Alternatively, telmisartan may be used in combination with a thiazide-type diuretic such as hydrochlorothiazide, which has been shown to have an additive blood pressure-lowering effect.
For the prevention of cardiovascular events, the recommended dose is 80 mg once daily. It is not yet established whether doses lower than 80 mg provide the same degree of cardiovascular protection. During the initial period of treatment, particularly during the first few weeks, blood pressure should be monitored regularly, and the dose should be adjusted as needed to achieve the target levels recommended by current ESC/ESH guidelines.
Important Dosing Information
Micardis tablets should be taken once daily at the same time each day. They can be taken with or without food. The tablets should be swallowed whole with a sufficient amount of water. The blood pressure-lowering effect is generally achieved within 3 hours of the first dose, with the maximum antihypertensive effect typically reached after 4 to 8 weeks of treatment.
Elderly
No dose adjustment is generally necessary for elderly patients. However, elderly patients may be more susceptible to the blood pressure-lowering effects of telmisartan, particularly if they have reduced kidney function or are taking diuretics. In such cases, careful blood pressure monitoring during the initiation of therapy is recommended. Starting at the lower end of the dose range and titrating gradually may help to minimize the risk of hypotension.
Missed Dose
If you forget to take your daily dose of Micardis, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a forgotten dose. It is helpful to take Micardis at the same time every day to help you remember. Some patients find it useful to associate taking their medicine with a daily routine, such as breakfast or bedtime.
What to Do If You Miss a Dose
Take the missed dose as soon as you remember, unless it is nearly time for the next scheduled dose. Never take two doses at once. If you frequently forget doses, speak with your doctor or pharmacist about strategies to improve adherence, such as pill organizers or reminder apps.
Overdose
Limited information is available regarding overdose with telmisartan in humans. The most likely signs of an overdose would be an excessive drop in blood pressure (hypotension) and a rapid heart rate (tachycardia). A slow heart rate (bradycardia) may also occur as a reflex response. If overdose occurs, treatment should be symptomatic and supportive. This may include placing the patient in a supine position, administering intravenous fluids to expand blood volume, and monitoring vital signs. Telmisartan is not removed by hemodialysis. If you suspect an overdose, contact your local poison control center or seek immediate medical attention.
What Are the Side Effects of Micardis?
Like all medicines, Micardis can cause side effects, though not everybody gets them. The most commonly reported side effects include dizziness, upper respiratory tract infections, and gastrointestinal disturbances. Serious but rare side effects include angioedema (severe allergic swelling), sepsis, and significant changes in kidney function. Most mild side effects improve as your body adjusts to the medication.
The safety profile of telmisartan has been extensively studied in large clinical trials involving tens of thousands of patients. Overall, telmisartan is well tolerated, with a side effect profile similar to placebo in many studies. The incidence of adverse effects leading to treatment discontinuation in clinical trials was comparable between telmisartan and placebo groups. The following list categorizes the known side effects by frequency, based on data from clinical trials and post-marketing surveillance.
Common Side Effects
- Low blood pressure (hypotension), including orthostatic hypotension, in patients treated for cardiovascular risk reduction
Uncommon Side Effects
- Urinary tract infection, upper respiratory tract infection (including pharyngitis and sinusitis)
- Anemia (decreased hemoglobin)
- High potassium levels (hyperkalemia)
- Insomnia, depression, anxiety
- Fainting (syncope), vertigo, dizziness
- Slow heart rate (bradycardia), low blood pressure when standing up (orthostatic hypotension)
- Shortness of breath (dyspnea), cough
- Abdominal pain, diarrhea, nausea, bloating
- Itching (pruritus), increased sweating (hyperhidrosis), drug rash
- Back pain, muscle cramps, muscle pain (myalgia)
- Kidney impairment (including acute renal failure)
- Chest pain, weakness (asthenia), flu-like illness
- Elevated blood creatinine
Rare Side Effects
- Sepsis (including fatal outcome in rare cases)
- Angioedema (swelling of the face, lips, tongue, or throat)
- Decreased platelet count (thrombocytopenia)
- Severe allergic reaction (anaphylactic reaction)
- Low blood sugar in diabetic patients (hypoglycemia)
- Rapid heart rate (tachycardia)
- Dry mouth, taste disturbance (dysgeusia)
- Abnormal liver function, hepatic disorder
- Eczema, hives (urticaria), severe skin reactions
- Joint pain (arthralgia), tendon pain, pain in extremities
- Elevated uric acid levels (hyperuricemia)
- Elevated liver enzymes (ALT, AST)
Very Rare Side Effects
- Interstitial lung disease (inflammation of the lung tissue)
Contact your doctor or go to the nearest emergency department immediately if you experience any signs of angioedema (rapid swelling of the face, lips, tongue, or throat that may cause difficulty breathing or swallowing), signs of sepsis (high fever, chills, rapid breathing, confusion, skin rash), or a severe allergic reaction (difficulty breathing, severe dizziness, widespread rash). These are rare but potentially life-threatening conditions that require urgent medical intervention.
It is important to understand that the list above may not include all possible side effects. If you notice any symptoms that you think may be related to Micardis, even if they are not listed here, you should inform your doctor or pharmacist. You can also report suspected side effects to your national medicines regulatory authority. Reporting side effects helps to provide ongoing safety information about this medicine.
Many of the milder side effects, such as dizziness or gastrointestinal discomfort, tend to occur during the first few weeks of treatment and often improve as your body adjusts to the medication. If side effects persist or become bothersome, your doctor may adjust the dose or recommend an alternative treatment. Do not stop taking Micardis without first consulting your doctor, as abruptly discontinuing antihypertensive therapy can lead to a rebound increase in blood pressure.
How Should You Store Micardis?
Store Micardis in its original packaging to protect the tablets from moisture. Do not store above 30 degrees Celsius (86 degrees Fahrenheit). Keep out of the sight and reach of children. Do not use Micardis after the expiry date stated on the carton and blister.
Proper storage of medicines is essential to ensure they remain safe and effective throughout their shelf life. Telmisartan tablets are sensitive to moisture, which is why the manufacturer specifically recommends keeping them in the original blister or bottle packaging until you are ready to take a dose. Removing tablets and storing them in a separate pill organizer may expose them to moisture and potentially affect their quality.
The storage temperature should not exceed 30 degrees Celsius (86 degrees Fahrenheit). There is no need to refrigerate Micardis. Store the tablets in a dry place, away from direct sunlight and sources of heat. As with all medicines, keep Micardis out of the reach and sight of children to prevent accidental ingestion.
Check the expiry date on the packaging before taking a tablet. The expiry date refers to the last day of that month. Do not use Micardis after this date. If you have tablets that have expired, do not dispose of them via household waste or wastewater. Ask your pharmacist about the proper way to dispose of unused or expired medicines, in order to help protect the environment.
What Does Micardis Contain?
Each Micardis tablet contains telmisartan as the active ingredient, available in 20 mg, 40 mg, and 80 mg strengths. The tablets also contain inactive ingredients including povidone K25, meglumine, sodium hydroxide, sorbitol (E420), and magnesium stearate, which serve as excipients to ensure the tablet is manufactured correctly and dissolves properly.
Understanding the composition of your medicine is important, particularly if you have known allergies or intolerances to specific excipients. The active substance in Micardis is telmisartan. Each tablet is clearly marked with its strength to allow for easy identification:
- Micardis 20 mg: Each tablet contains 20 mg telmisartan
- Micardis 40 mg: Each tablet contains 40 mg telmisartan
- Micardis 80 mg: Each tablet contains 80 mg telmisartan
The other ingredients (excipients) in Micardis tablets include:
- Povidone K25: A binder that helps hold the tablet together
- Meglumine: A solubilizing agent that helps the active ingredient dissolve
- Sodium hydroxide: Used for pH adjustment during manufacturing
- Sorbitol (E420): A sugar alcohol used as an excipient; relevant for patients with hereditary fructose intolerance
- Magnesium stearate: A lubricant that prevents the tablet ingredients from sticking to machinery during production
Sorbitol (E420): This medicine contains sorbitol. If you have been told by your doctor that you have an intolerance to some sugars, or if you have hereditary fructose intolerance, a rare genetic disorder in which a person cannot break down fructose, talk to your doctor before taking this medicine.
Sodium: Micardis tablets contain less than 1 mmol sodium (23 mg) per tablet, which means they are essentially sodium-free. This is relevant for patients on a controlled sodium diet.
Frequently Asked Questions About Micardis
References
- European Medicines Agency (EMA). Micardis – Summary of Product Characteristics. Available at: www.ema.europa.eu/en/medicines/human/EPAR/micardis
- World Health Organization (WHO). WHO Model List of Essential Medicines, 23rd List (2023). Geneva: World Health Organization.
- Williams B, Mancia G, Spiering W, et al. 2018 ESC/ESH Guidelines for the management of arterial hypertension. European Heart Journal. 2018;39(33):3021-3104. Updated ESC/ESH recommendations 2023.
- The ONTARGET Investigators. Telmisartan, Ramipril, or Both in Patients at High Risk for Vascular Events. New England Journal of Medicine. 2008;358(15):1547-1559. doi:10.1056/NEJMoa0801317
- British National Formulary (BNF). Telmisartan. National Institute for Health and Care Excellence (NICE). Available at: bnf.nice.org.uk/drugs/telmisartan
Editorial Team
This article was written and reviewed by the iMedic Medical Editorial Team, consisting of licensed physicians with specialization in cardiology, internal medicine, and clinical pharmacology.
All content has been medically reviewed according to international guidelines from the European Society of Cardiology (ESC), the European Medicines Agency (EMA), and the World Health Organization (WHO). Evidence level: 1A based on systematic reviews and randomized controlled trials.
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