Meds and you

Updated 11 February 2013


Telmisartan is often prescribed to relax and widen blood vessels in persons with high blood pressure.


Telmisartan is the active ingredient of Micardis.

Telmisartan is also one of multiple active ingredients found in Co-Micardis (telmisartan + hydrochlorothiazide).

General information

Telmisartan is often prescribed to relax and widen blood vessels in persons with high blood pressure. As a result, blood pressure is lowered and the heart's workload is reduced.

It is of particular use among patients taking drugs such as enalapril, captopril and related products (ACE inhibitors), which cause a dry and irritating cough. While still providing the same benefit, telmisartan reduce the likelihood of coughing.

Telmisartan may be used on its own or in combination with other medication for high blood pressure.

The first few doses may cause dizziness if you get up suddenly from sitting or lying down. It is advised to get up carefully until you know how this drug affects you.

Telmisartan should not be used if you are pregnant or planning to become pregnant. Adequate contraception is advised in women of childbearing age.

How does it work?

Telmisartan blocks the effect of angiotensin II, a naturally occurring substance that narrows blood vessels. As a result, blood vessels widen and high blood pressure is reduced.

Fast facts

Drug schedule: Schedule 3

Available as: Tablets

What does it do? Telmisartan lowers blood pressure and reduces the workload on the heart

Overdose risk: Medium

Dependence risk: Low

Available as a generic? No

Available on prescription only? Yes

User information

Onset of effect: Maximum effect is reached within 6 weeks.

Duration of action: Up to 24 hours.

Dietary advice: This medication can be taken with or without food.

Stopping: Premature stopping may mean symptoms return, or even worsen symptoms develop.

Prolonged use: No problems anticipated. Your doctor may keep an eye on blood potassium levels.

Special precautions

Alert your doctor before using this drug if:

  • You have liver or kidney disease,
  • You have congestive heart failure,
  • You have a narrowing to the arteries of the kidneys,
  • You are allergic to ANY medicine, or
  • You are taking other medication.

Pregnancy: Avoid. Potential risk to the foetus has been reported. Consult your doctor before use, or if you are planning to fall pregnant.

Breastfeeding: Avoid. This medication is passed through breast milk and may affect your baby adversely. Consult your doctor before use.

Porphyria: Avoid. It is unknown how this medication may affect your condition. Consult your doctor before use.

Infants and children: This medication is not intended for use in children.

Elderly: Caution is advised in the elderly as a reduced dose may be needed in patients above the age of 75.

Driving and hazardous work: Caution is advised as use of this medication may lead to dizziness, light-headedness and/or sedation. Avoid such activities until you know how it affects you.

Alcohol: Avoid concomitant use of alcohol.

Possible side effects:

Side effect


Consult your doctor



Only if severe

In all cases






Diarrhoea/ constipation



Nausea, diarrhoea



Taste disturbance



Skin rash/ itch



Cough/ difficulty breathing



Tiredness/ Unwell feeling




Drug interactions:

Anaesthetic drugs

May lower blood pressure further


May cause potassium toxicity


May lower blood pressure further


Increased risk of lithium toxicity

Non-steroidal anti-inflammatory drugs

May reduce effect of telmisartan

Potassium supplements

May cause potassium toxicity


May reduce effect of telmisartan

Overdose action

A small overdose is no cause for concern. In case of intentional large overdose, seek emergency medical attention. Symptoms may include dizziness and fainting.

Recommended dosage

Adults: 40-80mg once daily

This material is not intended to substitute medical advice, but is for informational purposes only. Please consult a physician for specific treatment and recommendations.


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