BMA Concise Guide to Medicine & Drugs

Methylphenidate

Brand names Concerta XL, Equasym XL, Medikinet XL, Ritalin

Used in the following combined preparations None

QUICK REFERENCE

Drug group Nervous system stimulant

Overdose danger rating High

Dependence rating Medium

Prescription needed Yes

Available as generic Yes

GENERAL INFORMATION

Methylphenidate is related to amfetamine and shares similar stimulant properties. Paradoxically, however, methylphenidate is used, under specialist supervision, to treat overactivity in children with severe, persistent attention deficit hyperactivity disorder (ADHD). Children with moderate ADHD should only receive this medicine when psychological treatments have been unsuccessful. In all cases, the drug should be part of an overall treatment programme for ADHD. Growth may be retarded in children receiving methylphenidate and should be closely monitored. However, if affected, growth often returns to normal once the drug is stopped. Methylphenidate is also used to treat narcolepsy in adults and children.

INFORMATION FOR USERS

Your drug prescription is tailored for you. Do not alter dosage without checking with your doctor.

How taken/used Tablets, XL tablets, XL capsules.

Frequency and timing of doses 1 or 2 x daily (an extra bedtime dose may be needed) swallowed whole, not chewed. Take before meals.

Dosage range ADHD 5mg (2.5mg under 6 years) – 100mg daily. Narcolepsy 10–60mg daily.

Onset of effect 1–2 hours.

Duration of action 3–6 hours (up to 9 hours for XL preparations).

Diet advice None.

Storage Keep in original container at room temperature out of the reach of children.

Missed dose Take next dose at the usual time. Do not take a double dose.

Stopping the drug Do not stop the drug without consulting your doctor; symptoms may recur.

OVERDOSE ACTION

Seek immediate medical advice. Although an occasional unintended dose is unlikely to be a cause for concern, a large overdose can be extremely dangerous. Take emergency action if a seizure occurs.

POSSIBLE ADVERSE EFFECTS

Adverse effects from methylphenidate are common but rarely serious. The common side effects include nausea, abdominal discomfort, dry mouth, irritability, agitation, aggression, rash, and palpitations. More rarely, the drug may cause depression. If nausea, abdominal discomfort, or dry mouth are severe, discuss with your doctor. Other side effects should also be discussed with your doctor. In some cases, the side effects may be difficult to interpret because of pre-existing behavioural problems. In each case, a careful assessment should be made by a specialist at regular intervals.

INTERACTIONS

SSRI and tricylcic antidepressants Methylphenidate can increase blood levels of these drugs. Reduced doses may be required.

MAOI antidepressants When taken with methylphenidate, there is a risk of an extreme rise in blood pressure. Concomitant use of these drugs should be avoided.

Phenytoin Methylphenidate increases blood levels of phenytoin. Reduced dose of phenytoin may be required.

Oral anticoagulants (e.g. warfarin) The anticoagulant effect of these drugs is increased by methylphenidate.

SPECIAL PRECAUTIONS

Be sure to tell your doctor if:

· You have a history of heart problems.

· You have a family history of Tourette’s syndrome.

· You have a drug dependency.

· You have epilepsy.

Pregnancy Safety in pregnancy not established. Discuss with your doctor.

Breast-feeding Safety in breast-feeding not established. Discuss with your doctor.

Infants and children Dose varies according to age.

Over 60 Not usually prescribed.

Driving and hazardous work Avoid such activities until you have learned how methylphenidate affects you.

Alcohol Avoid. Effects of methylphenidate may be enhanced by alcohol.

PROLONGED USE

No problems expected in adults. Methylphenidate may retard growth in children if used for prolonged periods.

Monitoring Regular monitoring of growth should be carried out when methylphenidate is used for prolonged periods in children.