Like all medicines eplerenone can cause side effects, although not everyone gets them. Side effects often improve as your body gets used to the medicine.
Common side effects
These common side effects of eplerenone happen in more than 1 in 100 people. They're usually mild and do not last long. There are things you can do to help cope with them:
Feeling dizzy
If eplerenone makes you feel dizzy, especially when you stand up, stop what you're doing and sit or lie down until you feel better. Do not drive, ride a bike or operate machinery.
If this continues for more than a few days, speak to your doctor as you may need your potassium levels checked.
Headaches
Make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Ask your pharmacist to recommend a painkiller. Talk to your doctor if the headaches do not go away or are severe.
Difficulty sleeping (insomnia)
Avoid caffeine (such as tea, coffee, cola, energy drinks and chocolate) in the afternoon and evening. Keep your bedroom dark and quiet, and try going to bed at the same time each day. Try not to watch TV or use your mobile phone before going to bed. Instead, try to relax for an hour before bedtime.
Coughing
Sometimes, your cough will get better on its own. Talk to your doctor if it carries on, bothers you, or stops you sleeping.
Feeling or being sick (nausea and vomiting)
Take eplerenone with or just after a meal.
If you're being sick, take small, regular sips of water or squash so you do not get dehydrated (ask your doctor how much fluid you can drink). Speak to a pharmacist if you have signs of dehydration, such as peeing less than usual or having dark, strong-smelling pee.
If you take the combined contraceptive pill or the progestogen-only pill and you're being sick, your contraception may not protect you from pregnancy. Check the pill packet for advice.
You can also talk to your doctor or pharmacist if the advice on how to cope does not help and these side effects bother you.
Serious side effects
Serious side effects after taking eplerenone are less common and happen in less than 1 in 100 people.
Call your doctor or call 111 straight away if:
- you have muscle cramps, diarrhoea, or feel sick or weak – your potassium levels may have increased and you may need a blood test
- you're peeing less than usual or have dark, strong-smelling pee, feel thirsty or feel dizzy or light-headed – these can be signs of dehydration
- you have diarrhoea, are peeing less than usual, are feeling or being sick, and feel drowsy or confused – these can be signs of loss of kidney function
Immediate action required: Call 999 or go to A&E if:
- you have an irregular or fast heartbeat (your heart feels like it's pounding or is beating a lot faster than normal)
- you have chest pain – this needs to be checked out as chest pain is a possible sign of a heart attack
Serious allergic reaction
In rare cases, eplerenone may cause a serious allergic reaction (anaphylaxis).
Immediate action required: Call 999 now if:
- your lips, mouth, throat or tongue suddenly become swollen
- you're breathing very fast or struggling to breathe (you may become very wheezy or feel like you're choking or gasping for air)
- your throat feels tight or you're struggling to swallow
- your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
- you suddenly become very confused, drowsy or dizzy
- someone faints and cannot be woken up
- a child is limp, floppy or not responding like they normally do (their head may fall to the side, backwards or forwards, or they may find it difficult to lift their head or focus on your face)
You or the person who's unwell may also have a rash that's swollen, raised, itchy, blistered or peeling.
These can be signs of a serious allergic reaction and may need immediate treatment in hospital.
Other side effects
These are not all the side effects of eplerenone. For a full list, see the leaflet inside your medicine packet.
You can report any suspected side effect using the Yellow Card safety scheme.