Telmisartan

Telmisartan is a prescription only medication that is used to treat those with high blood pressure (also known as hypertension).

Overview

Telmisartan is part of a family of drugs called angiotensin II receptor blockers (ARB), which block the substance produced by the body that causes the blood vessels to tighten and create higher pressure in the blood flow.

Telmisartan works by relaxing the vessels to ease the flow of blood throughout the body, in order to decrease blood pressure and increase the flow of oxygen and blood to the heart.

Telmisartan is also used as a preventative medication. Typically prescribed to those under 55 years old with a high risk of developing higher blood pressure in older age, the medication trains the blood vessels to relax. Patients that are typically prescribed telmisartan before developing high blood pressure are those suffering from conditions such as diabetes and heart problems.

High blood pressure is common among older adults and those with heart conditions or diabetes. High pressure in the blood vessels can put extra strain on the heart and the arteries. If this problem continues long-term, it can create damage to the blood vessels in the kidney, heart and brain. This damage can result in very serious consequences, such as heart failure, kidney failure or stroke. Medication, lifestyle and diet changes are recommended to lower blood pressure and decrease the risk of suffering a heart attack or a stroke.

Telmisartan can be prescribed on its own or in conjunction with other drugs to treat high blood pressure. It is also sold under the brand name Micardis in the United States.

Conditions treated

  • High blood pressure (hypertension)

Type of medicine

  • Oral tablet

Side effects

There can be various side effects experienced by patients taking telmisartan, particularly those that are at the beginning of a new prescription. These patients should be monitored closely and at regular intervals as prolonged side effects can be dangerous and can be a sign that the medicine is not working properly. In these cases, another medication may be prescribed. You should always tell your doctor if you experience severe or prolonged side effects as a result of telmisartan.

Most side effects, however, are not harmful and are just a result of the body adapting to telmisartan in the bloodstream. Some side effects include, but are not limited to:

  • Blocked nose and symptoms of the common cold
  • Pain in the back
  • Pain the sinuses
  • Stomach aches or pains
  • Diarrhea
  • Feeling excessively tired or drowsy
  • Weakness
  • Mild skin rash or spots
  • Back pain

There are some symptoms that you may experience that could be serious. These are very rare, but you must call your doctor as soon as possible if you notice you are developing any of the following:

  • A feeling you might be about to faint
  • Shortness of breath, even when carrying out mild tasks
  • Swelling of the hands, or feet
  • Slow heart rate
  • Muscle weakness
  • Tingly feeling in the skin (particularly in hands or feet)
  • Chest pain
  • Difficulty urinating, or painful urination

Dosage

As a treatment for hypertension

The dose that your doctor will prescribe you will depend on a range of factors relating to your overall health, and any other conditions you are suffering from or medication you are taking.

The general starting dose is 40 mg, taken orally in the form of a tablet, once per day. Once your body is used to this medication, you will be switched to a maintenance dose of between 40 mg and 80 mg per day. If your dosage is increased, you will still need to take this at the same time, once per day.

Patients that are put on a course of telmisartan usually see an effect on lowering their blood pressure with two weeks. Patients will reach the maximum effect within four weeks. Therefore the drug is usually prescribed in four week periods.

As a treatment for cardiovascular risk reduction

For preventing cardiovascular issues, adults are usually prescribed an 80 mg per day dose from the beginning of treatment. It is not known if dosages below 80 mg have an impact in lowering the risk of cardiovascular mortality.

For patients taking this dosage for cardiovascular risk reduction, it is necessary to closely monitor the blood pressure. Other medications that lower blood pressure may also be adjusted or removed.

Major drug interactions

There are some medications that you should not take when taking telmisartan. This is because they can cause major drug interactions. When a drug interacts with another it could lead to ineffectiveness of treatment – or even dangerous side effects for the patient. This is why it is extremely important for patients to be honest and comprehensive about any other medication they are taking or have taken in the past. There are some medications that interact with telmisartan, but which can still be taken at the same time; this may just alter the dose that your doctor or pharmacist will prescribe. These are called minor or moderate interactions; they can have some impact, but it may not be dangerous.

There are 71 drugs that have been found to have a major interaction with telmisartan. These are:

  • aliskiren
  • aliskiren, amlodipine
  • aliskiren, amlodipine, hydrochlorothiazide
  • aliskiren, hydrochlorothiazide
  • aliskiren, valsartan
  • amiloride
  • amiloride, hydrochlorothiazide
  • aminophylline, ephedrine, phenobarbital, potassium iodide
  • amlodipine, benazepril
  • amlodipine, perindopril
  • benazepril
  • benazepril, hydrochlorothiazide
  • bisacodyl, polyethylene glycol 3350, potassium chloride, sodium bicarbonate, sodium chloride
  • bisacodyl, sodium biphosphate, sodium phosphate
  • captopril
  • captopril, hydrochlorothiazide
  • chlorpheniramine, codeine, phenylephrine, potassium iodide
  • citric acid, potassium bicarbonate
  • citric acid, potassium bicarbonate, sodium bicarbonate
  • citric acid, potassium citrate
  • citric acid, potassium citrate, sodium citrate
  • diltiazem, enalapril
  • enalapril, felodipine
  • enalapril, hydrochlorothiazide
  • ephedrine, phenobarbital, potassium iodide, theophylline
  • ephedrine, potassium iodide
  • fosinopril
  • fosinopril, hydrochlorothiazide
  • hydrochlorothiazide, lisinopril
  • hydrochlorothiazide, moexipril
  • hydrochlorothiazide, quinapril
  • hydrochlorothiazide, spironolactone
  • hydrochlorothiazide, triamterene
  • hyoscyamine, methenamine, methylene blue, phenyl salicylate, sodium biphosphate
  • hyoscyamine, methenamine, methylene blue, sodium biphosphate
  • iodine, potassium iodide
  • lidocaine, potassium chloride
  • lisinopril
  • lvp solution with potassium
  • methenamine, sodium biphosphate
  • moexipril
  • parenteral nutrition solution w/ electrolytes
  • perindopril
  • potassium acetate
  • potassium acetate, potassium bicarbonate, potassium citrate
  • potassium acid phosphate
  • potassium bicarbonate
  • potassium bicarbonate, potassium chloride
  • potassium bicarbonate, potassium citrate
  • potassium bicarbonate, sodium bicarbonate
  • potassium chloride
  • potassium chloride, sodium chloride
  • potassium citrate
  • potassium citrate, sodium citrate
  • potassium gluconate
  • potassium iodide
  • potassium iodide, theophylline
  • potassium phosphate
  • potassium phosphate, sodium phosphate
  • quinapril
  • ramipril
  • sodium biphosphate, sodium phosphate
  • spironolactone
  • sulfamethoxazole, trimethoprim
  • tizanidine
  • trandolapril
  • trandolapril, verapamil
  • triamterene
  • trimethoprim

There are also 474 drugs that have a moderate interaction with telmisartan and three drugs that have a minor interaction with the medication. [ref 1]

Warnings

As with any medication, there are small risks involved with consumption. Your doctor will be able to decide whether telmisartan is safe and right for you, based on a number of factors about your medical history and current condition.

Food and alcohol interactions

When prescribing a course of telmisartan, your doctor will likely advise you on a healthier diet you can adopt to lower the symptoms of high blood pressure. In addition to ensuring a healthy diet, there are also some foods and drinks that you should not consume. These are:

Alcohol

As with any medication, keep your alcohol consumption to a minimum when taking this prescription. Alcohol can seriously impair how effective your drugs are in treating your condition. Telmisartan is most effective when the patient cuts out alcohol completely. However, if you decide not to cut out alcohol, you may consume it in moderation without severely impairing the effectiveness of the drug.

When consumed together, ethanol (alcohol) and telmisartan may create unwanted side effects and be less effective at lowering your blood pressure. Patients who consume both may experience fainting, light-headedness, dizziness, changes to the pulse and/or heart rate, headache and loss of judgement. These symptoms are more likely to be present in patients that are newer to the drug, so should be closely monitored. If you do consume alcohol and telmisartan and find that you are experiencing any side effects like those above, you should refrain from partaking in tasks that require acute mental awareness, such as driving and operating dangerous machinery. Do not immediately stop taking telmisartan if you are experiencing symptoms of mixing alcohol and telmisartan; instead consult your doctor first for advice.

Potassium salts

You should avoid salt substitutes that contain potassium as these can cause the levels of potassium in the blood to rise. This then can lead to weakness, confusion, tingling, irregular heartbeat or heavy legs. This also applies to potassium supplements or any vitamin products containing the substance.

Allergies

Always tell your doctor if you have experienced an allergic reaction to this medication or any similar medications in the past. Also, be upfront about allergies to other substances such as food dyes, food types, animals, preservatives and anything else. Some allergies may mean that telmisartan is not the right medication for you, and an alternative medicine could be more effective.

Other diseases

Always tell your doctor if you have been diagnosed with any other conditions, or if you have symptoms of any other conditions. Other diseases may not be compatible with your medication, and you may make that condition worse by taking it.

Diseases that have been known to interact with telmisartan are:

  • Renal/Liver Disease
  • Diabetes
  • Renal Artery Stenosis
  • Hypotension
  • Renal Impairment
  • Angioedema
  • Chf
  • Hyperkalemia
  • Liver disease
  • Kidney disease
  • Electrolyte imbalance – e.g. high potassium in the blood
  • Fluid imbalances
  • Heart failure

Pregnancy and breastfeeding

This medication has been found to cause a risk to unborn fetuses. Therefore, an alternative medication may be prescribed to pregnant women. If a patient discovers she is pregnant while on a course of telmisartan, taking the medication should be stopped as soon as possible; telmisartan can cause fetal toxicity.

However, there are some cases in which the benefits of the medication for the pregnant patient may outweigh the risks to the unborn baby. A qualified healthcare professional will be able to make that judgement.

There is no evidence that telmisartan causes risk to breastfeeding babies; however, this is due to a lack of studies and data. As with pregnancy, a doctor may advise that the benefits to the mother outweigh any risks to the new-born child.

Children

There are currently no studies into the impact of telmisartan on children. Due to the nature of the conditions for which telmisartan is prescribed – typically experienced by older patients – there is little data on the effectiveness of telmisartan as a treatment for younger people. Safety for children taking telmisartan is not known.

Missing a dose

Telmisartan is most effective when you take it at the recommended times each day. However, there will no doubt be times when you accidentally miss a dose. You should take it as soon as you remember. Do not take the dose if it is almost time for the next one. Do not attempt to “double up” on doses to make up for any you may have previously forgotten.

Overdose

If you think you or someone else may have taken an overdose of telmisartan, you should call Poison Control as soon as possible. Always call 911 if someone has become unconscious or stopped breathing as a result of telmisartan. You should be prepared to let the responding healthcare professional how much of the drug has been taken, when it was taken and what was taken.

Storage

You should always store your medication in the box or tub it was supplied in. Telmisartan should be stored at room temperature (21 degrees centigrade) and away from any direct sources of heat or light (away from sunlight, radiators etc.). Always keep the medication in a dry; do not store it in your bathroom or anywhere it could become moist.

Always store your medication out of the reach and sight of children and other people for whom it was not intended. Your medication is for your use only, so do not give it to anyone else. If your medication is supplied in a tub with a lockable lid, always keep it in that container and keep the lid locked when not in use. This prevents children from being able to access the container. Also take care to store out of the reach of pets, as animal consumption is also dangerous.

Disposal

There are special ways to dispose of unwanted medication. Do not attempt to flush or grind your unwanted tablets, and do not throw them out with the trash. Instead, the best way to dispose of unwanted or out-dated medication is by using an FDA take-back scheme. These are available across the country and you can easily arrange for your tablets to be collected. [ref 2]

If you don’t have access to a take-back scheme, you can dispose of the drugs yourself, just take extra precautions to make sure they don’t end up in the wrong hands, or become a danger to chidren or animals. First, get a sealable plastic bag. Then, take your medication out of its box and put it in the bag. Then, mix in some inedible substance – the FDA recommends cat litter, used coffee beans or soil – and seal up the bag. You can then place it in the trash can with regular garbage.

Summary

Telmisartan is used widely as an effective treatment for the lowering blood pressure in patients with hypertension. It is also used to lower the risk of developing high blood pressure in those under 55 that have been deemed at significant risk, for example those with diabetes.

There are various studies that have shown that the drug can be used as a safe and reliable treatment and, as a result, it is one of the most common drugs prescribed to treat the condition. [ref 3]

However, patients that are new to the drug should be carefully monitored, and doctors should take extra care to extract as many details as possible from the patient about his or her health and lifestyle; there are many drugs that have been found to interact with telmisartan and mixing these can put the patient’s health at risk. Patients should also be aware of the potential risks and side effects involved in taking telmisartan, particularly pregnant women and younger patients.

Telmisartan is intended as a mid-term treatment for high blood pressure and, once the pressure in the blood vessels is successfully lowered, the patient can either maintain the dose or come off the medication. This is usually after a four-week period.

Telmisartan is most effective as a treatment for high blood pressure when the patient makes other lifestyle changes alongside. These include improvements in diet, increased amounts of exercise and reductions in detrimental substances such as alcohol. Subsequently, a doctor will usually advise the patient on how to improve lifestyle to complement the prescription.

Resources
Last Reviewed:
December 22, 2017
Last Updated:
December 22, 2017