Signs and symptoms of acute overdosage, resulting principally from overstimulation of the central nervous system and from excessive sympathomimetic effects, may include the following: vomiting, agitation, tremors, hyperreflexia, muscle twitching, convulsions (may be followed by coma), euphoria, confusion, hallucinations, delirium, sweating, flushing, headache, hyperpyrexia, tachycardia, palpitations, cardiac arrhythmias, hypertension, mydriasis, and dryness of mucous membranes.
Consult with a Certified Poison Control Center regarding treatment for up-to-date guidance and advice.
Treatment consists of appropriate supportive measures. The patient must be protected against self-injury and against external stimuli that would aggravate overstimulation already present. Gastric contents may be evacuated by gastric lavage. In the presence of severe intoxication, use a carefully titrated dosage of a short-acting barbiturate before performing gastric lavage. Other measures to detoxify the gut include administration of activated charcoal and a cathartic.
Intensive care must be provided to maintain adequate circulation and respiratory exchange; external cooling procedures may be required for hyperpyrexia.
Efficacy of peritoneal dialysis or extracorporeal hemodialysis for methylphenidate overdosage has not been established.
Methylphenidate is contraindicated in patients with marked anxiety, tension and agitation, since the drug may aggravate these symptoms.
Hypersensitivity to Methylphenidate
Methylphenidate is contraindicated in patients known to be hypersensitive to methylphenidate or other components of the product.
Methylphenidate is contraindicated in patients with glaucoma.
Methylphenidate is contraindicated in patients with motor tics or with a family history or diagnosis of Tourette’s syndrome (see ADVERSE REACTIONS).
Monoamine Oxidase Inhibitors
Methylphenidate is contraindicated during treatment with monoamine oxidase inhibitors, and also within a minimum of 14 days following discontinuation of a monoamine oxidase inhibitor (hypertensive crises may result).
Hypertension and Other Cardiovascular Conditions
Methylphenidate is contraindicated in patients with severe hypertension, angina pectoris, cardiac arrhythmias, heart failure, recent myocardial infarction, hyperthyroidism or thyrotoxicosis (see WARNINGS).