ADHD, Narcolepsy, and Methylphenidate (Ritalin®)

Overview

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental condition characterised by persistent inattention, hyperactivity, and impulsivity. It affects both children and adults and may significantly interfere with academic, occupational, and social functioning. ADHD arises from a combination of genetic, neurological, and environmental factors.

Narcolepsy is a chronic neurological sleep disorder marked by excessive daytime sleepiness and disrupted sleep–wake regulation. Treatment often requires long-term, individualised care.

Methylphenidate (Ritalin®): Indications and Mechanism

Methylphenidate is a prescription stimulant used to treat ADHD and, in selected cases, narcolepsy. It is marketed under brand names such as Ritalin®, Concerta®, Focalin XR®, and Medikinet MR®.
Ritalin® and methylphenidate refer to the same medication — Ritalin® is a brand name.

Methylphenidate increases the availability of dopamine, noradrenaline, and serotonin in the brain. In individuals with ADHD, this helps reduce excessive sensory input and supports:

• Improved attention and concentration
• Reduced impulsivity and hyperactivity
• Better organisational skills

In narcolepsy, it may help improve daytime alertness.

Other Medications for Narcolepsy

Alternative treatments for narcolepsy include:

• Modafinil (Provigil®) and Armodafinil (Nuvigil®), which promote wakefulness
• Sodium oxybate (Xyrem®), which improves nighttime sleep and reduces daytime sleepiness

These medications differ in mechanism, dosing, and side-effect profile. Selection depends on symptom pattern and patient response and should be guided by a healthcare professional.

Onset, Duration, and General Use

• Onset of effect: ~30 minutes after oral administration
  (up to 2 hours for extended-release formulations)
• Duration: ~4–8 hours, depending on formulation

When used as prescribed, methylphenidate is generally well tolerated. Common side effects include reduced appetite, sleep disturbance, mild headache, and gastrointestinal discomfort, which often improve over time.

Safety, Mixed Use, and When to Seek Help

Administration and Mixed Use Risks

• Intravenous use of methylphenidate is contraindicated. Tablet fillers may cause embolism, including pulmonary or cerebral vessel blockage.
• Intranasal use may damage nasal tissue and increase infection risk; harm-reduction guidance should be followed.
• Alcohol may increase agitation, impaired judgment, and cardiovascular strain.
• Mixing with other stimulants or serotonergic substances (e.g. MDMA, amphetamines) increases the risk of serotonin syndrome.

Contraindications and Interactions

• Do not combine methylphenidate with monoamine oxidase inhibitors (MAOIs). Serious reactions may occur up to 14 days after MAOI discontinuation.
• Caution is advised when combined with psychedelic substances, as stimulant effects may worsen anxiety and intrusive thoughts.
• Avoid combination with tramadol, as both agents increase the risk of seizures and stroke.

When to Seek Emergency Medical Help

Seek urgent medical care if any of the following occur after methylphenidate use, particularly with high doses or mixed substances:

• Chest pain or irregular heartbeat
• Shortness of breath
• Seizures or loss of consciousness
• Severe agitation, confusion, or hallucinations
• High fever, excessive sweating, or shivering
• Sudden weakness, numbness, vision changes, or difficulty speaking

Possible signs of serotonin syndrome include:

• Muscle rigidity or twitching
• Rapid heart rate
• Fever
• Altered mental state

Clinical Safety Note

Methylphenidate is effective for many patients when used under medical supervision. Polysubstance use and non-medical use significantly increase health risks. Patients should inform their healthcare provider of all medications and substances they are using to support safe treatment decisions.