methylphenidate
central nervous system stimulant· Brands: Ritalin, Concerta, Medikinet, Equasym, XenidatePO
Mechanism of action
Methylphenidate is a central nervous system stimulant that increases the levels of dopamine and noradrenaline in the brain by inhibiting their reuptake. It blocks the dopamine transporter (DAT) and noradrenaline transporter (NET), particularly in the prefrontal cortex and striatum, thereby enhancing neurotransmission and improving attention, focus, and impulse control.
Pharmacokinetics
Methylphenidate is well absorbed after oral administration but undergoes extensive first-pass metabolism, resulting in low bioavailability. It is rapidly hydrolysed to ritalinic acid, which is inactive. Peak plasma concentrations occur about 1 to 2 hours after ingestion for immediate-release formulations and are prolonged for extended-release versions. It is primarily metabolised by carboxylesterase 1 (CES1), and metabolites are excreted in urine. The elimination half-life is approximately 2 to 3 hours, although therapeutic effects may persist longer. Different formulations have varying release profiles, affecting duration of action.
Indications & dosing
Attention deficit hyperactivity disorder (ADHD) in children and adolescents
Immediate-release formulation. Titrate from 5 mg twice daily, adjust weekly.
- pediatric · PO: 5–20 mg BID-TID · Immediate-release formulation. Titrate from 5 mg twice daily, adjust weekly.
Attention deficit hyperactivity disorder (ADHD) in adults
Titrate to response; may require divided doses. Consider extended-release.
- adult · PO: 5–20 mg BID-TID · Titrate to response; may require divided doses. Consider extended-release.
Narcolepsy in adults
Take before meals. Start with 10 mg twice daily; usual range 10-20 mg twice daily.
- adult · PO: 10–20 mg BID · Take before meals. Start with 10 mg twice daily; usual range 10-20 mg twice daily.
Contraindications & precautions
- Known hypersensitivity to methylphenidate or any ingredient
- Angle closure glaucoma
- Symptomatic cardiovascular disease, including severe hypertension, heart failure, or arrhythmias
- Hyperthyroidism
- Pheochromocytoma
- Concomitant use of MAO inhibitors within the previous 14 days
- History of substance misuse or dependence · May increase risk of misuse; weigh benefits
- Monitor heart rate and blood pressure, particularly in patients with cardiovascular risk factors.
- Use with caution in patients with a history of seizures or epilepsy.
- Monitor growth in children and adolescents on long-term therapy.
- Assess for potential misuse and dependence in patients with a history of substance use.
- Use with caution in patients with psychiatric disorders such as psychosis, mania, or bipolar disorder.
- Taper gradually on discontinuation to avoid withdrawal symptoms.
Adverse effects
- Decreased appetite
- Insomnia
- Headache
- Nausea
- Anxiety
- Tachycardia
- Psychosis or maniaserious
- Seizuresserious
- Cardiovascular events (e.g., myocardial infarction, stroke)serious
- Priapismserious
Monitoring, pregnancy & toxicity
- Blood pressure · Baseline and regularly during treatment
- Heart rate · Baseline and regularly during treatment
- Weight and growth in children · Every 6 months or as clinically indicated
- Psychiatric symptoms (e.g., agitation, psychosis) · At each review
- Appetite and sleep · At each review
- Pregnancy: Not recommended in pregnancy; use only if potential benefit outweighs risk.
- Toxicity: Agitation, confusion, hallucinations, psychosis · Supportive care; benzodiazepines for agitation and seizures.
- Toxicity: Hypertension, tachycardia, arrhythmias · IV fluids; beta-blockers for tachyarrhythmias; monitor ECG.
- Toxicity: Hyperthermia, sweating, rhabdomyolysis · Cooling measures; IV fluids; monitor creatine kinase.
- Toxicity: Seizures · Benzodiazepines (e.g., diazepam); monitor for CNS depression.
Clinical notes
Methylphenidate is used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. Doses are individualised, starting low and titrated according to response and tolerability. Common side effects include insomnia, reduced appetite, headache, nervousness, and increased heart rate. It may cause growth suppression in children, so monitoring of height and weight is recommended. Methylphenidate is a controlled substance with a potential for misuse and should be used cautiously in patients with a history of substance abuse. It is contraindicated in severe cardiac disease, hypertension, and symptomatic cardiovascular disorders. It is not recommended in pregnancy and breastfeeding. Prescription should be under specialist guidance.
Log in to read the full methylphenidate monograph
A free account unlocks the complete drug reference, the interaction checker, prescription practice and every other learning tool.
BNF; local formulary