Medicines & Supplements A to Z > Ritalin


Last updated on 19/10/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Methylphenidate


DRUG CLASS: Central nervous system agents

SUB CLASS: Norepinephrine–dopamine reuptake inhibitors (NDRIs)

USED FOR: Attention deficit hyperactivity disorder (ADHD), Narcolepsy 

– 10mg (tablets)
– 10mg, 20mg, 30mg (extended-release capsules)

What is Ritalin for?

Ritalin is a brand product that contains Methylphenidate, which is a central nervous system stimulant. It works by blocking the reuptake of dopamine and noradrenaline, hence increasing their levels. These are hormones in the brain responsible for producing alertness and concentration. It is used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy.

How to use it?

Ritalin is available as tablets or long-acting capsules (Ritalin LA). 

Ritalin tablets
For attention deficit hyperactivity disorder (ADHD) and narcolepsy
Adult: usual dose is 20-30 mg daily in 2-3 divided doses, and administered preferably 30-45 minutes before meals. Maximum total daily dosage is 60 mg.
Children ≥6 years and adolescents: 5 mg twice daily given before breakfast and lunch. The dose can be increased by 5-10 increments mg/day at weekly intervals up to a maximum dose of 60 mg/day (in 2-3 divided doses).

Ritalin LA capsules
For attention deficit hyperactivity disorder (ADHD) only
Adult: 10-20 mg once daily in the morning. The dose can be increased based on response and tolerability in 10 mg increments at weekly or greater intervals up to a maximum dose of 60 mg/day.
Children ≥6 years and adolescents: 20 mg once daily. The dose can be increased based on response and tolerability in 10 mg increments at weekly intervals up to a maximum dose of 60 mg/day. 

What are the side effects of Ritalin?

Common side effects of Ritalin include mood swings, decreased appetite, heart palpitations, nausea, vomiting, and insomnia.

Who should not take Ritalin?

People who are allergic to methylphenidate or any component of the formulation.

Pharmacist Tips:

– Children taking this medicine may stunt growth, make sure the patients are closely monitoring their height when taking this medicine.
– The capsule is designed to not be digested and therefore can be seen in stools.

Common dosing schedule:
Ritalin LA capsules should be given in the morning, with or without food. If you are unable to swallow the capsule, open it and the contents may be sprinkled onto a tablespoon of applesauce or yogurt. Swallow mixture immediately or within 10 minutes without chewing. Do not crush, chew, or divide capsule contents.

Ritalin tablets should be administered 30-45 minutes before meals (preferably breakfast and lunch). If you are unable to sleep when medication is taken late in the day, the last dose should be taken before 6 p.m.. 

This schedule is for reference only, adjustments may be made according to individual needs.

Some common medications Ritalin may interact with:
– Anticonvulsants, e.g. Phenobarbital, Phenytoin
– Monoamine oxidase inhibitors, e.g. Rasagiline, Selegiline
– Tricyclic antidepressants, e.g. Clomipramine, Imipramine

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Ritalin in Hong Kong?

In Hong Kong, Ritalin is a prescription only medicine, and requires a prescription from a doctor to be purchased in a pharmacy. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.

For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at

Need more information?

For detailed information about the use of Ritalin in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.

Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.