Methylphenidate misuse: risks, warning signs and getting help

The NHS says methylphenidate is used to treat attention deficit hyperactivity disorder (ADHD) and sometimes narcolepsy. It belongs to a group of medicines called stimulants, which work by increasing activity in the brain, particularly in areas that help control attention and behaviour. It comes as standard tablets and as slow release tablets and capsules.

Under supervision it is a well-established treatment. The NHS says it usually takes a few weeks to work fully, can take time to find the right type and dose, and should start to work within 30 to 60 minutes once the right dose is found. Misuse refers to taking it in a way that is not as prescribed or for someone it was not prescribed for.

The NHS describes taking methylphenidate more often than the prescription says, or at a higher dose, as not taking it properly. MHRA guidance for prescribers uses the term diversion for transfer of the medicine from the person it was prescribed for to someone for whom it is not prescribed, and asks clinicians to look out for diversion, misuse and abuse.

The NHS leaflet advice also shows how misuse can arise by accident. It says slow release tablets should not be crushed or broken because the medicine will not work properly, that you should take the next dose as planned rather than doubling up after a missed dose, and that you should stick to the same brand.

Methylphenidate can cause a small increase in blood pressure and heart rate even when taken as prescribed, which is why the NHS says doctors usually check blood pressure and pulse every 6 months. Higher doses and use outside medical supervision remove that safety net.

The NHS lists serious side effects: mood or personality changes, fast or irregular heartbeats, seeing, feeling or hearing things that are not real, and facial tics, with a 999 or A&E response to thoughts of harming yourself or others, chest pains, stroke symptoms or fits. MHRA guidance says methylphenidate could cause or worsen psychiatric disorders such as depression, suicidal thoughts, hostility, anxiety, agitation, psychosis and mania, and recommends prompt cardiac evaluation for symptoms such as palpitations, exertional chest pain and unexplained fainting.

The NHS also says alcohol can increase the effects of methylphenidate and make side effects more likely, advises people with problems with drugs or alcohol to check with their doctor first, and says mixing with some other medicines is dangerous. It specifically says not to take methylphenidate with MAOI antidepressants or within 14 days of stopping them, because this can cause a sudden increase in blood pressure.

The NHS says the amount that causes an overdose is different for everyone, and that you should get medical advice if you take more than your prescribed dose. It advises calling 999 or going to A&E if you have taken more than prescribed and have a fit or seizure, or a fast, slow or irregular heartbeat. If you have taken more than prescribed without symptoms, it says to contact NHS 111 for advice now.

Do not drive yourself to A&E. The NHS says to ask someone to drive you or call 999, and to bring the packet or leaflet, any remaining medicine and any other medicines you take. The same urgency applies if someone has taken methylphenidate that was not prescribed to them.

On addiction, the NHS says you are unlikely to have problems if you follow your doctor's instructions, but the risk may increase if you take it more often or at a higher dose than prescribed. If you become physically dependent you are more likely to get withdrawal symptoms, such as depression, if you suddenly stop.

The NHS advises never stopping suddenly without talking to your doctor, who may reduce the dose gradually. If you are struggling with how you are taking methylphenidate, or are tempted to take more, say so. Prescribers are used to having these conversations, and the aim is to adjust the plan rather than to judge.

The NHS suggests attending your check-up with the doctor every 12 months to see if you still need the medicine, and says that you may not need to take it for life. For those wanting alternatives, it says other ADHD medicines such as dexamfetamine, lisdexamfetamine or atomoxetine exist, and psychological treatments such as behavioural therapy and talking therapy can also help.

If you think someone else is taking your medicine, or you are worried about taking methylphenidate that was not prescribed to you, speak to your prescriber, pharmacist or GP. Do not give your medicine to anyone else. For drug-related support more broadly, GP surgeries and local drug and alcohol services can help.

ADHD medicines are prescribed through NHS services or by private specialists. Both are subject to the same controlled-drug rules and monitoring expectations, including blood pressure and pulse checks and annual review. If you receive prescriptions from more than one source, tell each prescriber so that the full picture of your medicines is known and the risk of taking too much is reduced.