Metadate

Conspecific secretions and excretions may stimulate pest rodents to consume bait. An example is the metad, or soft-furred rzt, RattusmeltadapalUdior, of the grasslands and crop fields of India. In a laboratory test, 1% conspecific urine from males or females added to the diet of millet increased food consumption by 32 to 70%. The metads also stayed longer in the half of the cage with the urine-treated food than in that with untreated food, and scent marked more there. The males marked with sebum, the females with urine. Male urine tended to be more effective, and males responded more than females (Soni and Prakash, 1987). 

Tablets, extended-release 10 mg (c-/7) Metadate ER (Celltech), Methylin ER (Alliant)... 

Absorption - Rapidly and well absorbed from the Gl tract, methylphenidate achieves peak blood levels in 1 to 3 hours. Peak plasma levels occur in children in 4.7 hours for the SR tablets and 1.9 hours for the regular tablets. Mean times to reach peak plasma concentrations across all doses of Concerta occurred between 6 and 10 hours. Plasma half-life for Metadate CD is reportedly 6.8 hours. SR and ER tablets are more slowly but as extensively absorbed as regular tablets. 

Many psychomotor stimulants possess activities similar to those of amphetamine and have been discussed previously (see Chapter 10). Of primary importance to our discussion of the psychomotor stimulants are amphetamine Adderall, Benzedrine, Dexedrine), methampheta-mine (Desoxyn), and methylphenidate (Concerta, Ritalin, Metadate, Methylin). 

Brand Name(s) Concerta, Metadate CD, Metadate ER, Methylin, Methylin ER, Ritalin, Ritalin LA, Ritalin SR... 

The recently introduced product Concerta is a once-a-day administration MPH delivery system called OROS (osmotically released). This delivery system creates an ascending plasma level pattern instead of the peak-and-valley pharmacokinetic profile seen in the IR preparations. Similar extended-delivery bead-technology, double-pulse preparations have been introduced for Metadate-CD at 10, 20, and 30 mg (Green-hill et ah, 2002, in press) for the spheroidal technology of Ritalin-EA, and for Adderall-XR preparations (McGough et ah, 2002, in press). Beaded stimulant preparations mix IR and delayed-release beads in a capsule. The patient can swallow the capsule whole or sprinkle the contents in food if pill taking is difficult for the child. 

Greenhill, L., Findling, R., Swanson, J., and Metadate Study Group. A double-blind, placebo-controlled, study of modified-release MPH MR in children with attention-deficit/hyperactivity disorder. Pediatrics, in Press. 

Commercially available psychostimulants include methylphenidate (Ritalin, Methylin, Metadate, Con-... 

Methylphenidate and D-amphetamine are both short-acting compounds, with an onset of action within 30 to 60 minutes and a peak clinical effect seen usually between 1 and 2 hours after administration, lasting 2 to 5 hours. Therefore, multiple daily administrations are required for a consistent daytime response. The amphetamine compound Adderall, the sustained-release preparations of methylphenidate and dextroamphetamine, and pemoline are all intermediate-acting compounds with an onset of action within 60 minutes and a peak clinical effect seen usually between 1 and 3 hours after administration and maintained for up to 8 hours (8 hours with metadate C.D. and Ritalin LA 12 hours with Concerta), allowing for a single dose for the entire school day. Adderall XR is a 12 hour preparation. 

Metadate-CD, Ritalin-LA, Focalin, others Dexedrine 5 mg t 5, 10, 15 mg sustained-release spansules Adderall 5, 10, 20, 30 mg... 

Methylin Chewable Methylin Oral solution Metadate ER... 

Ritalin-SR, ADHD May be given once every morning in place of total daily dose of Methylin ER, immediate-release methylphenidate to achieve an estimated 8-hour duration of Metadate ER action. 

Metadate CD ADHD Persons >6 years old start at 20 mg qam increase by 10-20 mg/day at weekly intervals as needed to attain response. 

Methylphenidate Ritalin-SR Ritalin LA Metadate ER Metadate CD Concerta Slowly absorbed tablet Capsule with 50% methylphenidate dose as immediate-release beads and 50% as delayed-release beads Slowly absorbed tablet with methylphenidate incorporated in a wax matrix tablet, allowing gradual diffusion Capsule that provides 30% of methylphenidate dose hy immediate-release beads and 70% of the dose by extended-release beads Tablet that contains approximately 22% of the methylphenidate dose in an immediate-release capsule overcoat and 78% within the tablet that is released by an osmotic process over an extended period... 

After drugs are approved, the FDA tracks reports of errors due to drug name confusion and spreads the word to health professionals, along with recommendations for avoiding future problems. For example, the FDA has reported errors involving the inadvertent administration of methadone, a drug used to treat opiate dependence, rather than the intended Metadate ER (methylphenidate) for the treatment of attention-deficit/hyperactivity... 

Diffucaps Eurand Povidone, HPMC, ethyl cellulose Combination of immediate and sustained release Metadate CD... 

Methylphenidate is marketed in the United States under the prescription names Concerta, Metadate, Methylin, and Ritalin (26). It is available in immediate and sustained-release formulations for the treatment of attention deficit/hyperactivity disorder (ADHD) and the symptomatic management of narcolepsy (a disorder characterized by excessive daytime sleepiness). 

Methylphenidate (Ritalin Ritalin SR Concerta Metadate) doses range from 5 mg/day bid to a maximum of 60 mg/day, divided fid. Side effects include nervousness, insomnia, loss of appetite and headaches. 

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