The higher the dose of prednisolone that you take and the longer you take it for, the greater the chance of side effects. You're less likely to get side effects if you take a relatively low dose of prednisolone daily.
If you have been taking prednisolone for more than a few weeks, check with your doctor before stopping it suddenly to reduce your chances of withdrawal side effects.
Some side effects, such as stomach upset or mood changes, can happen straight away. Others, such as getting a rounder face, happen after weeks or months.
Common side effects
These common side effects of prednisolone happen in more than 1 in 100 people. There are things you can do to help cope with them:
Weight gain
If you have to take prednisolone for more than a few weeks, it's likely that you'll put on weight. Prednisolone can make you hungrier and also can make you retain more water in your body.
Try to eat well without increasing your portion sizes. Regular exercise will also help to keep your weight stable.
Once you stop taking prednisolone, your appetite and the way your body retains water should return to normal.
Indigestion
Take prednisolone with food to reduce the chances of stomach problems. It may also help if you avoid rich or spicy food while you're taking this medicine.
If symptoms carry on, ask your doctor if you may benefit from taking an additional medicine to protect your stomach.
Problems sleeping (insomnia)
Take prednisolone in the morning so the levels are the lowest at bedtime.
Feeling restless
If you're feeling restless when you're trying to sleep, take prednisolone in the morning so the levels are the lowest at bedtime.
Sweating a lot
Try wearing loose clothing and use a strong anti-perspirant. If this does not help, talk to your doctor as you may be able to try a different medicine.
Mild mood changes
Prednisolone can affect your mood in different ways. Talk to your doctor if you are finding it hard to cope.
Speak to a doctor or pharmacist if the advice on how to cope does not help and any of these side effects bother you or last more than a few days.
Serious side effects
You are more likely to have a serious side effect if you take a higher dose of prednisolone or if you have been taking it for more than a few weeks.
Call a doctor or call 111 straight away if you get:
- a high temperature, chills, a very sore throat, ear or sinus pain, a cough, more saliva or a change in colour of saliva (yellowish and possibly with streaks of blood), pain when you pee, mouth sores or a wound that will not heal – these can be signs of an infection
- sleepy or confused, feeling very thirsty or hungry, peeing more often, flushing, breathing quickly or breath that smells like fruit – these can be signs of high blood sugar
- weight gain in your upper back or belly, "moon face" (a puffy, rounded face), very bad headaches and slow wound healing – these can be signs of Cushing's syndrome
- a very upset stomach or you're being sick (vomiting), very bad dizziness or passing out, muscle weakness, feeling very tired, mood changes, loss of appetite and weight loss – these can be signs of adrenal gland problems
- muscle pain or weakness, muscle cramps, or changes in your heart rate – these can be signs of low potassium levels
- severe stomach pain, severe back pain, severe upset stomach or you're being sick – these can be signs of pancreas problems
- breathlessness
- swelling in your arms or legs
- changes in your eyesight
- any bruising or bleeding that is not normal
- red or black poo
Immediate action required: Call 999 or go to A&E if:
- you have black or dark brown vomit or you're vomiting blood
Mood changes
You may notice mood changes and mental health problems while taking prednisolone.
Talk to your doctor or contact 111 if you have any mood changes including:
- feeling depressed
- feeling high, or moods that go up and down
- feeling anxious, having problems sleeping, difficulty in thinking, or being confused and losing your memory
- feeling, seeing or hearing things that do not exist (hallucinations)
- having strange and frightening thoughts, changing how you act, or having feelings of being alone
The higher the dose, the more intense the mood changes can be.
Go to 111.nhs.uk or call 111.
Immediate action required: Call 999 or go to A&E if:
- you have thoughts about harming yourself or ending your life
Do not drive to A&E. Ask someone to drive you or call 999 and ask for an ambulance.
Bring all the medicines you take with you.
Serious allergic reaction
In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to prednisolone.
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.
Do not drive yourself to A&E.
The person you speak to at 999 will give you advice about what to do.
Long-term side effects
Taking prednisolone for a long time can lead to side effects such as:
- thinner bones (osteoporosis)
- poorly controlled diabetes
- eyesight problems
- high blood pressure (hypertension)
Children and teenagers
Taking prednisolone at higher doses for a long time can slow down the normal growth of children and teenagers.
Your child's doctor will monitor their height and weight carefully for as long as they're taking this medicine. This will help them spot any slowing down of your child's growth and change their treatment if needed.
Even if your child's growth slows down, it does not seem to have much effect on their eventual adult height.
Talk to your doctor if you're worried. They'll be able to explain the benefits and risks of giving your child prednisolone.
Other side effects
These are not all the side effects of prednisolone. For a full list, see the leaflet inside your medicine packet.
Reporting side effects
You can report any suspected side effect using the Yellow Card safety scheme.
Visit the Yellow Card website for more information about reporting side effects.