Like all medicines, methylphenidate can cause side effects, although not everyone gets them.
Common side effects of methylphenidate
These common side effects of methylphenidate may happen in more than 1 in 100 people. Side effects will depend on the type and brand of methylphenidate you're taking.
There are things you can do to help cope with them:
Headaches
Make sure you rest and drink plenty of fluids. Painkillers such as paracetamol can help. Talk to your doctor if the headaches are severe or do not go away.
Trouble sleeping (insomnia)
If you're finding it hard to sleep, try taking the last dose of methylphenidate more than 6 hours before bedtime.
Loss of appetite
It may help to take methylphenidate with a meal.
You may notice some weight loss during the first few months of treatment. You'll probably put this weight back on once you're used to the medicine.
If you notice that you are losing a lot of weight, speak to your doctor.
Stomach ache
Try to rest and relax. It can help to eat and drink slowly and have smaller and more frequent meals. Putting a heat pad or covered hot water bottle on your stomach may also help.
If you're in a lot of pain, or the pain does not go away, speak to your pharmacist or doctor.
Dry mouth
This usually gets better quite quickly. Taking sips of water and eating citrus fruits (like oranges or satsumas) can help.
Feeling or being sick
Stick to simple meals and do not eat rich or spicy food if you feel sick. It might help to take methylphenidate with or after a meal or snack.
If you are being sick try taking small, frequent sips of water or squash to avoid dehydration. See your doctor if you are being sick or having severe stomach pains.
If you take the combined contraceptive pill or progestogen-only pill and you're being sick, your contraception may not protect you from pregnancy. Check the pill packet for advice.
Keep taking your medicine but tell your doctor if these side effects bother you or do not go away.
Your doctor should review your medicine at least once a year to make sure there are no problems.
Serious side effects
Serious side effects are uncommon and happen in less than 1 in 100 people.
Methylphenidate can cause a small increase in your blood pressure and heart rate. Your doctor will usually measure your blood pressure and pulse every 6 months.
Call your doctor or call 111 straight away if you:
- have mood or personality changes, such as feeling aggressive, irritable, depressed, anxious or tense
- have fast or irregular heartbeats (palpitations)
- start seeing, feeling or hearing things that are not real (hallucinations)
- have started to get facial tics, which are quick, little movements in the muscles of your face that you cannot control – if this happens, your doctor may stop your treatment
Immediate action required: Call 999 or go to A&E if you have:
- thoughts about harming yourself or others
- chest pains
- symptoms of a stroke, such as drooping on one side of the face, weakness on one side of the body, and slurring your words
- fits or seizures
Serious allergic reaction
In rare cases, methylphenidate 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.
Do not drive yourself to A&E.
The person you speak to at 999 will give you advice about what to do.
Other side effects
These are not all the side effects of methylphenidate. For a full list, see the leaflet inside the medicines 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.