Eplerenone tablets (Inspra)

Take eplerenone tablets once a day.

Do not use salt substitutes while you are taking eplerenone.

Make sure your doctor knows about any other medicines you are taking alongside eplerenone.

Type of medicineAldosterone antagonist
Used forHeart failure
Also calledInspra®
Available asTablets

Heart failure means that your heart is not functioning as well as it should. In a healthy heart, a set amount of blood enters the heart during each heartbeat and is pumped out again. If you have heart failure, your heart cannot cope with pumping the full amount of blood in each heartbeat.

If you have heart failure which affects the left ventricle of your heart (left-sided heart failure), it may cause you to be short of breath. It can also be associated with a cough. This is generally worse when you are active (for example, walking up hill) or when you are lying flat in bed.

Eplerenone is prescribed alongside other medicines to help prevent worsening of heart failure in people who have left-sided heart failure. It works by blocking the action of a substance in your body called aldosterone. High levels of aldosterone can cause changes that result in heart failure. By blocking aldosterone, eplerenone helps prevent heart failure from worsening.

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking eplerenone it is important that your doctor knows:

  • If you have any problems with the way your kidneys work, or any problems with the way your liver works.
  • If you have been told you have high levels of potassium in your blood.
  • If you are pregnant, trying for a baby or breast-feeding.
  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
  • If you have ever had an allergic reaction to a medicine.
  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The manufacturer's leaflet will give you more information about eplerenone and a full list of the side-effects which you may experience from taking it.
  • Take eplerenone exactly as your doctor tells you to. You will be prescribed one tablet to take every day. There are two strengths of tablet - you will be prescribed the lower (25 mg) strength tablet to begin with, but this will be increased to the 50 mg strength tablet within a few weeks.
  • Swallow the tablet whole with a drink of water. It is not important whether you take eplerenone before or after food.
  • Unless your doctor tells you otherwise, you can generally take eplerenone at a time of day you find easy to remember. It is best, however, to try to take your doses at the same time of day each day, as this will help you to remember to take your doses regularly.
  • If you forget to take a dose, take one as soon as you remember, if this is during the same day as your dose was due. If you do not remember until the following day, skip the forgotten dose and just take the dose that is due. Do not take two doses at the same time to make up for a missed dose.
  • Try to keep your regular appointments with your doctor. This is so your doctor can check on your progress. The salt balance in your bloodstream may be upset by eplerenone and your doctor will want you to have a blood test from time to time to check the amount of potassium in your blood.
  • Try to avoid things with a high potassium content, such as 'salt substitutes'. This is so the level of potassium in your body does not become too high.
  • For most people with heart failure, regular exercise is advised. The fitter the heart, the better it will pump. The level of exercise recommended varies from person to person, so before you start to exercise, get the go-ahead from your doctor.
  • Your doctor may advise you to make some lifestyle changes, like losing weight if you are overweight, reducing the amount of alcohol you drink and stopping smoking. Following this advice will help to improve the health of your heart.
  • If you buy any medicines, check with a pharmacist that they are suitable to take with your other medicines. This is because some painkillers called non-steroidal anti-inflammatory drugs (NSAIDs) may not be recommended for you.
  • If you are having an operation or dental treatment, tell the person carrying out the treatment which medicines you are taking.
  • Treatment with eplerenone is usually long-term, so continue to take the tablets unless you are advised otherwise.

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with eplerenone. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Common eplerenone side-effects - these affect less than 1 in 10 people who take this medicineWhat can I do if I experience this?
Feeling dizzy or light-headedIf you begin to feel dizzy, lie down so that you do not faint, then sit for a few moments before standing. Do not drive or use tools or machines until you feel better. If this continues, speak with your doctor
Feeling sickStick to simple foods - avoid rich or spicy meals. If this continues, speak with your doctor
DiarrhoeaDrink plenty of water to replace lost fluids. If this continues, speak with your doctor
ConstipationEat a well-balanced diet and drink several glasses of water each day
Infections, cough, itchy skin rash, kidney problems, muscle spasmsSpeak with your doctor if you are concerned about any of these
Changes to blood tests (such as high blood potassium)Your doctor will check for this

If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

  • Keep all medicines out of the reach and sight of children.
  • Store in a cool, dry place, away from direct heat and light.

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Did you find this information useful?

Further reading & references

Original Author:
Helen Allen
Current Version:
Helen Allen
Peer Reviewer:
Prof Cathy Jackson
Document ID:
13597 (v3)
Last Checked:
18 December 2013
Next Review:
17 December 2016
The Information Standard - certified member

The information on this page is written and peer reviewed by qualified clinicians.

Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.