When to Stop

• Cardiovascular events: Sudden cardiac death has been reported in patients with structural cardiac abnormalities. Contraindicated in known structural heart disease, cardiomyopathy, serious arrhythmia, recent MI, uncontrolled HTN.
• Psychiatric events: Psychosis, mania, hallucinations (especially in patients with bipolar history). New-onset aggression. Rare but serious.
• Priapism: Documented adverse reaction to methylphenidate-class drugs, including children. Seek immediate medical attention.
• Peripheral vasculopathy / Raynaud's phenomenon: Methylphenidate-induced Raynaud's documented; rare but real. Most often resolves on discontinuation.
• Serotonin syndrome: Rare interaction with SSRIs/SNRIs/MAOIs; methylphenidate is not strongly serotonergic, but reported.
• Growth suppression (pediatric only): Modest effect on height velocity in children; most catch up at discontinuation. Not relevant for adults.
• Dependence / abuse: Schedule II for a reason. Dependence and tolerance with chronic high-dose or recreational use; abuse liability classed as moderate among addictive drugs (lower than amphetamines but real). Withdrawal: low mood, fatigue, hyperphagia, sleep changes — not as severe as amphetamine withdrawal.
• Weeks 1-4: cardiovascular calibration — daily morning HR + BP, watch for any chest pain, palpitations, fainting. Stop and seek care if any concerning cardiovascular symptoms.
• First 2-3 weeks: appetite/sleep tracking — if appetite drops >20% of baseline intake or sleep onset shifts >1 hr later, lower dose or discontinue.
• First month: mood tracking — irritability, anxiety, dysphoria during taper. If pattern worsens over weeks, discontinue.
• Ongoing if used: tolerance/escalation pressure — Schedule II self-management requires honest self-monitoring. If desire-to-take exceeds task-need, that's a signal to stop.