Methylphenidate oral

Memantine (Namenda) Methylphenidate, Oral (Concerta, Ritalin,... 

Methylphenidate, Oral (Concerto, Ritalin, Ritalin SR, Others) [Cll] [CNS Stimulant/Piperidine Derivative] WARNING w/Hx... 

Racemic f/zreo-methylphenidate was approved for the treatment of fatigue, nausea, and depression in 1955 under the brand name Ritalin , and was first used in children in 1958 with an approval for hyperkinetic disorder (ADHD) in 1960. Methylphenidate has an even shorter half-life than amphetamine, and its use in treating ADHD was limited by the fact that schoolchildren would need to visit a nurse during the day to take a second dose of this scheduled drug (in order to maintain efficacy throughout the entire school day). In humans, injecting methylphenidate produces effects similar to intravenous cocaine, but oral methylphenidate is adsorbed very slowly from the gut into the blood and takes an unusually long time (estimated 2.5 h) to reach a peak concentration... 

Methylphenidate is an inhibitor of drug metabolizing enzymes of the cytochrome P450 family and several interactions with drugs like some antiepileptics, antidepressants and oral anticoagulants, have been described. 

While some stimulants, such as amphetamine and methylphenidate, are taken orally, others are either volatilized for inhalation or snorted as the solid (nasal insufflation). It is necessary to convert cocaine and methamphetamine to their free base so that they can be volatilized. Methamphetamine and cocaine are also abused via the intravenous route. 

Volkow, N., Wang, G., Fowler, J., Gatley, S., Logan, J., Ding, Y., Hitzemann, R., and Pappas, N. (1998) Dopamine transporter occupancies in the human brain induced by therapeutic doses of oral methylphenidate. Am J Psychiatry 155 1325-1331. 

Hunt, R.D. (1987) Treatment effects of oral and transdermal cloni-dine in relation to methylphenidate—an open pilot study in ADDH. Psychopharmacol Bull 27 111—114. 

Modi NB, Wang B, Noveck RJ, et al Dose-proportional and stereospecific pharmacokinetics of methylphenidate delivered using an osmotic, controlled-release oral delivery system. J Clin Pharmacol 40 1141-1149, 2000h... 

Volkow, N.D., Wang, G.J., Fowler, J.S., et ah Relationship between blockade of dopamine transporters by oral methylphenidate and the increases in extracellular dopamine therapeutic implications. Swiapse 43(3) 181-187. 2002. 

Methylphenidate is chemically and pharmacologically similar to amphetamine. Both act by releasing norepinephrine and dopamine in brain. Both produce increased mental activity with little action on central and peripheral functions. It is well absorbed orally, metabolized and excreted in urine. 

More recently, a new oral, osmotic, extended-release formulation of methylphenidate (Concerta), with both an immediate and continuous release component, has been approved by the FDA (72). When taken once daily, it results in plasma levels similar to those achieved with a three-times-a-day schedule of the immediate-release formulation. In addition, serum concentrations appear to fluctuate less. The additional cost, however, is significant. 

Ritalin pills contain the hydrochloride salt methylphenidate. When the salt comes in contact with water, it yields hydrochloric acid. This is not a problem when the pills are taken orally, because hydrochloric acid is one of the digestive acids present in the stomach. When the drug is snorted, however, the corrosive acid can burn the tissues in nasal passages and cause open sores, nosebleeds, and even deterioration of the nasal cartilage. 

The convenience of once-a-day dosing for some drugs may also help increase sales. To make it even easier for parents to administer drugs to their children, on April 6, 2006, the FDA approved a skin patch for the delivery of methylphenidate (Ritalin) to children. A patch sounds a lot less ominous than a drug. Called Daytrana, the patch can be slapped on the child s hip for up to 9 hours at a time. When taken orally, methylphenidate has a shorter duration of action (3-6 hours), typically requiring a second dose handed out by the school nurse during the school day. 

Multiple involuntary movements, consisting of jaw grinding, oral dyskinesias, bilateral hand rolling, vermiform tongue movements, and bilateral choreiform movements of the digits, have been described in an 11-year-old boy taking thioridazine 150 mg/day and methylphenidate 10 mg bd (36). The methylphenidate was discontinued and within 4 weeks his movement disorder had completely disappeared. 

SYMPATHOMIMETICS CYTOTOXICS -PROCARBAZINE Co-administration of ephedrine, metaraminol, methylphenidate, phenylephrine or pseudoephedrine (including nasal and ophthalmic solutions) with procarbazine may cause a prolongation and t intensity of the cardiac stimulant effects and effects on BP, which may lead to headache, arrhythmias, hypertensive or hyperpyretic crisis The metabolism of sympathomimetics is impaired due to an inhibition of MAO It is recommended that sympathomimetics not be administered during and within 14 days of stopping procarbazine. Do not use any OTC nasal decongestants (sprays or oral preparations) or asthma relief agents without consulting the pharmacist/doctor... 

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