Most people with heart failure are treated with medication. Often you'll need to take two or three different medicines.
Some of the main medicines for heart failure include:
You may need to try a few different medicines before you find a combination that controls your symptoms but doesn't cause unpleasant side effects.
ACE inhibitors
Angiotensin-converting enzyme (ACE) inhibitors work by relaxing and opening up your blood vessels, which makes it easier for your heart to pump blood around the body.
Examples of ACE inhibitors include ramipril, captopril, enalapril, lisinopril and perindopril.
The most common side effect of ACE inhibitors is a dry, irritating cough. If you have a troublesome cough, an ACE inhibitor may be switched to an ARB.
ACE inhibitors can also cause your blood pressure to fall too low, and they may cause kidney problems. Your GP will monitor this.
Beta-blockers
Beta-blockers work by slowing your heart down and protecting your heart from the effects of adrenaline and noradrenaline, "fight or flight" chemicals produced by the body.
There are several different beta-blockers, but the main ones used to treat heart failure in the UK are bisoprolol, carvedilol and nebivolol.
Possible side effects of beta-blockers include dizziness, tiredness and blurred vision.
But most people taking them have either no or very mild side effects that become less troublesome with time.
Angiotensin receptor blockers (ARBs)
Angiotensin receptor blockers (ARBs) work in a similar way to ACE inhibitors, by relaxing blood vessels and reducing blood pressure.
They tend to be used as an alternative because they don't usually cause a cough, although they may not be quite as effective as ACE inhibitors.
Examples of ARBs include candesartan, losartan, telmisartan and valsartan.
Side effects of ARBs can include low blood pressure and high levels of potassium in your blood. Your doctor will carry out regular blood tests to monitor your potassium level.
Hydralazine with nitrate
Hydralazine in combination with nitrate can help relax and open up the blood vessels.
These medicines are sometimes prescribed by heart specialists (cardiologists) for people who are unable to take an ACE inhibitor or ARB.
Side effects can include headaches, a fast heartbeat and a pounding, fluttering or irregular heartbeat (palpitations).
Diuretics
Diuretics (water pills) make you pass more urine, and help relieve ankle swelling and breathlessness caused by heart failure.
There are many different types of diuretic, but the most widely used for heart failure are furosemide (also called frusemide) and bumetanide.
Possible side effects of diuretics include dehydration and reduced levels of sodium and potassium in the blood.
Aldosterone antagonists
Aldosterone antagonists work in a similar way to diuretics, but they don't cause reduced potassium levels. The most widely used aldosterone antagonists are spironolactone and eplerenone.
Spironolactone may cause enlarged breasts (gynaecomastia) in men, and breast tenderness and increased hair growth in women. Eplerenone can cause sleeping difficulties, dizziness and headaches.
The most serious side effect of these medicines is that they can cause the level of potassium in your blood to become dangerously high. Your doctor will carry out regular blood tests to check for this.
Sacubitril valsartan
Sacubitril valsartan is a new heart failure medication recommended by NICE. It's a single tablet that combines an ARB and a medication called a neprilysin inhibitor.
It's suitable for people with more severe heart failure, whose heart is only able to pump a reduced amount of oxygenated blood around the body despite taking other medication.
The most common side effects of sacubitril valsartan are low blood pressure, high potassium levels and kidney problems.
You can read more about sacubitril valsartan for treating chronic heart failure on the NICE website.
Ivabradine
Ivabradine is a medicine that can help slow your heart down, and is a useful alternative to beta-blockers if you can't take them or they cause troublesome side effects.
It can also be used alongside beta-blockers if they don't slow the heart enough.
Possible side effects include headaches, dizziness and blurred vision.
Digoxin
Digoxin, derived from the foxglove plant, can improve your symptoms by strengthening your heart muscle contractions and slowing down your heart rate.
It's normally only recommended for people who have symptoms despite treatment with ACE inhibitors, ARBs, beta-blockers and diuretics.
Possible side effects include dizziness, blurred vision, feeling and being sick, diarrhoea, and an irregular heartbeat.