Overdose methylphenidate

Markowitz JS, Logan BK, Diamond F, Patrick KS. Detection of the novel metabolite ethylphenidate after methylphenidate overdose with alcohol coingestion. J Clin Psychopharmacol 1999 19(4) 362-6. 

Levine B, Caplan YH, Kauffman G. Fatality resulting from methylphenidate overdose. J Anal Toxicol 1986 10(5) 209-210. 

Drug overdose Methylphenidate overdose has been reported [68, 69 ]. 

Paradoxical effects cognitive impairment and perseverative behavior are occasionally seen in children treated with psychostimulants. According to Greenhill et al. (1999) such phenomena are indicative of a drug overdose and will improve at dose reduction. Constriction of attention or overfocusing as a consequence of treatment with psychostimulants has been another critical issue (Breggin, 1999). Based on an extensive review of the literature and their own experience, Wilens and Biederman (1992) assert that there is no evidence of such phenomena at doses up to 1.0 mg/kg of methylphenidate. 

Information on pemoline s tolerance and toxicity is not available. However, as with almost any drag, there is a chance of psychological and/or physical dependence with excessive doses and/or long-term misuse (57). In comparison to methylphenidate and amphetamine, pemoline has the least potential for abuse (39). Benowitz (41) suggests that approximately 3 mg/kg pemoline should be considered life-threatening. Treatment for overdose is similar to what has been recommended for methylphenidate and amphetamine. In cases of overdose, the administration of chlorpromazine has been found useful for decreasing the amount of CNS overstimulation (57). 

The treatment of narcolepsy with psychostimulants such as amphetamine 2 (Adderall), and methylphenidate 3 (Ritalin) has been reported.3 However, these are schedule 2 DEA-controlled substances and have a potential risk of abuse, overdose, and dependence, which present substantial barriers to widespread use.4 As a result, there has been a significant effort to identify novel therapeutic agents for the... 

Methylphenidate (Ritalin). Ritalin is a sympathomimetic agent with psychostimulant properties similar to S(+)-amphetamine. It is widely used to treat attention deficit hyperactivity disorder (ADHD) in children and adults. There has been increasing diversion and abuse of methylphenidate among children and adults for its stimulant and purported aphrodisiac properties. In overdose, the clinical effects of methylphenidate are similar to those of amphetamine. Relatively few cases of serious overdose have been reported. 

The most common side effect of clonidine is dose-dependent sedation that usually subsides after 2 to 3 weeks of therapy. Of concern are reports of bradycardia, rebound hypertension, heart block, and sudden death. Four children have died on the combination of methylphenidate and clonidine however, complicating factors make it impossible to link the drug combination directly with the cause of death. Of 10,060 children exposed to clonidine and assessed by a poison control center over a 7-year period, moderate (19%) to major (2%) toxic effects (bradycardia, hypotension, and respiratory depression) including one death were reported. Overdoses, concurrent clonidine and stimulant administration, as well as missed doses of clonidine aU add to the risk of adverse cardiovascular events. Similar adverse-effect concerns apply to treatment with guanfacine, although its U2a selectivity may result in less sedation and hypotension than clonidine. ... 

Methylphenidate should not be used with monoamine oxidase inhibitors such as tranylcypromine. Symptoms of overdose may include euphoria, confusion, delirium, coma, toxic psychosis, agitation, headache, vomiting, dry mouth, mydriasis, self-injury, fever, diaphoresis, tremors, hyper-reflexia, muscle twitching, seizures, flushing, hypertension, tachycardia, palpitations, and arrhythmias. 

These cases support the findings of a retrospective chart review of 289 exposures and confirm the general opinion that methylphenidate has a high margin of safety and that full recovery is possible in cases of overdose with appropriate supportive interventions [70 ]. The toxic dose of methylphenidate in children is not certain. Doses of less than 1 mg/kg were not associated with adverse events [71 " ]. 

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