Ritalin

Overview

What are Ritalin and Ritalin LA?

Ritalin and Ritalin LA contain methylphenidate hydrochloride. Ritalin is a tablet designed to release medication immediately after ingestion. Ritalin LA, on the other hand, is a modified-release capsule for extended symptom control. Ritalin and Ritalin LA work by inhibiting the dopamine and norepinephrine reuptake into presynaptic neurons and thereby increasing these neurotransmitters in the extraneuronal space. The active ingredient for the two drugs is methylphenidate hydrochloride.

Global Name

• Generic name: Methylphenidate hydrochloride
• Brand name: Ritalin (Immediate-release), Ritalin LA (Long-acting) 

Usage

What is Ritalin used for?

Ritalin and Ritalin LA are used to treat Attention-Deficit/Hyperactivity Disorder (ADHD) in paediatric patients 6 years of age and older. Ritalin LA formulation is used to treat ADHD in adults. Ritalin is also indicated for the treatment of narcolepsy in adults (excessive daytime sleepiness with “sudden sleep” attacks.

How do you use Ritalin?

Dosage form:

• Tablet in strengths of 5 mg, 10 mg and 20 mg.    

• Extended-release capsule in strengths of 10 mg, 20 mg, 30 mg and 40 mg. 

Dosage information:

The dosage of Ritalin should be individualised according to the patient's clinical needs and responses. 

• ADHD

  • Paediatric Patients (6 years and older): Start with 5 mg Ritalin tablet once with twice daily (e.g. at breakfast and lunch) with weekly increment of 5 to 10 mg. The total daily dosage should be administered in divided doses. Start with 20 mg Ritalin LA capsule. A maximum dose should not exceed 60 mg.

  • Adults: The recommended starting dose of Ritalin LA is 20 mg once daily for patients new to methylphenidate. For methylphenidate-experienced patients, the doctor may adjust the dosage to an appropriate recommended level. Maximum daily dosage is 80 mg. 

• Narcolepsy 

  • Adults: Only the Ritalin is approved. The average daily dose is 20–30 mg in 2 to 3 divided doses, with a maximum of 60 mg per day. The final dose should be taken before 6 pm to avoid sleep disturbance.

Are the following suitable for getting the drug?

• Children: Both Ritalin & Ritalin RA are suitable for children aged 6 years or older for the treatment of ADHD.
• Adults: Ritalin LA is suitable for adults for the treatment of ADHD. Ritalin is also suitable for adults for the treatment of narcolepsy.
• Patients with renal impairment: No studies have been performed in this population.
• Patients with hepatic impairment: No studies have been performed in this population.

Who should not take Ritalin?

• Children: Not recommended for children under 6 years old.
• Geriatric patients: No studies performed in patients over 60 years of age.
• Pregnant women: Not recommended as insufficient experience with the use methylphenidate in pregnant women. Should be used only if the potential benefit justifies the potential risk to the foetus.
• Nursing mothers: Methylphenidate is excreted into breast milk in a milk-to-plasma ratio of 2.5, and a careful decision should be made whether to discontinue breastfeeding or Ritalin therapy.
  
  

Warnings and Precautions:

• Drug abuse and dependence: Be cautious with emotionally unstable patients.
• Cardiovascular: Risk of sudden death in patients with structural cardiac abnormalities. Monitor blood pressure and heart rate.
• Cerebrovascular: Regular assessment for the neurological/psychiatric signs and symptoms after starting Ritalin and Ritalin LA for patients with additional risk factors.
• Psychiatric: Can exacerbate behaviour, thought disorders, or induce psychotic/manic episodes. Monitor for aggressive behaviour and suicidal tendencies.
• Tics: Can induce or exacerbate motor/verbal tics.
• Serotonin Syndrome: Risk increases when used with serotonergic drugs (SSRIs, SNRIs).
• Glaucoma and increased intraocular pressure: close monitoring and evaluation by an ophthalmologist.
• Priapism: Prolonged, painful erections require immediate medical attention.
• Growth: Monitor height and weight in children; long-term use may cause slight growth retardation.
• Seizures: May lower the convulsive threshold; discontinue if seizures occur.
• Haematologic: Periodic blood counts recommended during long-term therapy.

Interactions and Contraindications of Ritalin:

• Interactions:
  • MAO Inhibitors: Contraindicated due to risk of hypertensive crisis.
  • Alcohol: Avoid alcohol as it exacerbates CNS adverse effects.
  • Anaesthetics: Risk of sudden blood pressure/heart rate increase during surgery.
  • Alpha-2 Agonists (e.g., Clonidine): Serious adverse events reported with concomitant use.
  • Other: Caution with anti-hypertensives, dopaminergic drugs (antipsychotics), and coumarin anticoagulants.
• Contraindications: 
  • Hypersensitivity to methylphenidate or to any of the excipients
  • Anxiety, tension
  • Agitation
  • Hyperthyroidism
  • Pre-existing cardiovascular disorders including severe hypertension, angina, arterial occlusive disease; heart failure, hemodynamically significant congenital heart disease, cardiomyopathies, myocardial infarction, potentially life-threatening arrhythmias and channelopathies (disorders caused by the dysfunction of ion channels).
  • During treatment with monoamine oxidase (MAO) inhibitors, or within a minimum of 2 weeks of discontinuing those drugs
  • Glaucoma
  • Phaeochromocytoma 
  • Diagnosis or family history of Tourette's syndrome
    

Side Effects

• Very common: Nervousness, insomnia, decreased appetite, nasopharyngitis, nausea and dry mouth
• Common: Abdominal pain, vomiting, dyspepsia, tachycardia, palpitations, headache, dizziness, drowsiness, tremor, rash, hyperhidrosis, weight decrease
• Very Rare: Angina pectoris, cerebrovascular disorders, convulsions, psychosis, thrombocytopenia

Pharmacist Tips

• Storage information: Store Ritalin and Ritalin LA at 20–25°C, allow 15–30°C excursions. Protect from light (Ritalin only formulation).
• Administration:
  • Ritalin: Take orally 2 to 3 times daily with or without food.
  • Ritalin LA: Take once daily in the morning, with or without food. Swallow the capsule whole with liquid. Do not chew or crush the capsule. For patients who are unable to swallow capsules, the contents may be sprinkled onto soft food and taken immediately.

Availability

Where are Ritalin and Ritalin LA available in Hong Kong?

Ritalin and Ritalin LA are prescription-only medications available through healthcare providers upon doctor’s prescription.

FAQs

What is the difference between Ritalin and Concerta?

Ritalin and Concerta both contain the same active ingredient, methylphenidate, but they differ mainly in their formulation, duration of action, and dosing schedule.

What are the possible side effects of Ritalin?

Common side effects include nervousness, insomnia and decreased appetite. 

How many Ritalin tablets/capsules can be taken in one day?

The number of tablets/capsules depends on the strength of each formulation prescribed.

How much does Ritalin cost?

Ritalin is a prescription-only medicine, and the price varies depending on the healthcare provider.