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Dexmethylphenidate chemical structure
| (R,R')-(+)-methyl 2-phenyl-2-(2-piperidyl)acetate|
| CAS number |
| ATC code |
| PubChem |
| DrugBank |
|Molecular weight||233.306 g/mol|
|Elimination half-life||2–4 hours|
|Routes of administration||Oral|
Dexmethylphenidate (sold commercially by Novartis as Focalin) is a pharmaceutical drug used to treat Attention Deficit Hyperactivity Disorder. It is very similar to Ritalin, but it only contains the d-isomer of methylphenidate. It is a stimulant that affects the central nervous system. Dexmethylphenidate has approximately a 6-hour duration of effect, and has been demonstrated to be more effective than methylphenidate at reducing the symptoms of childhood ADHD.
Dexmethylphenidate has a similar side-effect profile to Methylphenidate and can be administered without regard to food intake. Recently, it has become available in extended-release form, and has been shown to be as effective as d,l-methylphenidate, with flexible dosing and good tolerability.
Mode of Action
Dexmethylphenidate likely functions in the same manner as methylphenidate (Ritalin): It is a relatively mild, relatively long-lasting stimulant. Ritalin, as usually synthesized, is a racemate (consisting of two molecules with identical chemical structures but different chirality). Dexmethylphenidate consists of a single isomer, with the other (levomethylphenidate) removed. Dexmethylphenidate appears to be primarily responsible for the therapeutic activity of methylphenidate, while levomethylphenidate may (as with other inactive isomers) interfere with metabolism or cause unwanted side effects. Because of this, an individual's therapeutic dose of dexmethylphenidate will generall be half their therapeutic dose of methylphenidate.
The CAS number of enantiomerically pure dextro-methylphenidate is 19262-68-1.
Because dexmethylphenidate is a stimulant, the same concerns that apply to methylphenidate and other stimulant drugs should be considered: Reports of sudden cardiac death in children caused Canada to stop marketing Adderall XR (another stimulant used to treat ADHD) for a period in 2005. Heart problems have been reported, predominantly in young people taking ADHD stimulants, though the FDA has not concluded that the category of stimulants increase risk of cardiac problems for a person without a heart condition. Suicidal thinking has been reported in young people who are taking antidepressants at the same time they are taking an ADHD stimulant.
Not enough comparative studies on all ADHD stimulants have been conducted to know the comparative effectiveness of different drugs, although initial evidence does point to the superiority of dexmethylphenidate to methylphenidate. Genetic differences affect responses to these drugs and results will be different based on individual symptoms of ADD and ADHD. 
A complete treatment plan using Dexmethylphenidate is created to treat ADHD along with psychological, educational, social, and other treatments. One notion to the way it works is by re-establishing the balance of specific types of brain chemicals known as neurotransmitters. A person's ability to pay attention, stay focused on an activity, and control behavior problems are all areas that this treatment will cover. Also, listening skills may improve, there is a possibility it will help stop fidgeting, and maybe help to organize tasks better.
Disorders such as narcolepsy can be treated with this medication. The use of this medication to take care of severe depression or tiredness or to hold off sleep in people who do not have a sleep disorder is not how this medication should be used. Insomnia can be a result if Focalin is taken too late in the day. A total daily dose is around 20 milligrams or less and is prescribed by your doctor according to your needs. Do not switch between methylphenidate (Ritalin) and dexmethylphenidate (Focalin) unless the doctor says so; these are two different medicines and although they are for the same condition, they take care of it differently.
To get the most out of this medication use Focalin regularly and exactly as prescribed. If used in high doses or for an extended time (more than a few weeks) there is a possibility that you may become dependent on Focalin. Suddenly stopping use will most likely cause withdrawal. If you have any suicidal thoughts, depression, or any other mental/mood changes contact your doctor immediately. When stopping treatment of this medicine, to help prevent withdrawal reactions, you should gradually taper off the dose. Abnormal drug-seeking behavior (addiction/habit forming) although very unlikely, can occur. Do not take it more frequently, increase your dose, or use it for a longer time than prescribed; this will increase the chance of addiction. To lessen the chance of becoming addicted, stop the use of medication properly as directed. Tell your doctor if conditions worsen. In some cases your doctor may propose medication holidays; this is when you temporarily stop taking the medicine so your behavior can be re-evaluated. 
Trouble sleeping, nausea, stomach pain, headache, nervousness, loss of appetite, or weight loss are more commonly seen. Your doctor should be contacted if any of these conditions continue or get worse.
Without delay you should tell your doctor if any of these serious but unlikely effects occur: uncontrolled muscle movements (e.g., stiffness, twitching, shaking), high fever, outbursts of words/sounds, swelling of the ankles/feet, blurred vision, mental/mood/behavior changes (e.g., agitation, aggression, mood swings, depression, hallucinations, abnormal thoughts/behavior), extreme tiredness, and severe sweating. Also, there is a severe allergic reaction that can occur, but it is very unlikely. If you do get it, seek immediate medical attention. Trouble breathing, itching, a rash, swelling, or severe dizziness are all signs/symptoms of this allergic reaction.
Easy bleeding/bruising, shortness of breath, fainting, chest/jaw/left arm pain, sudden vision changes, signs of infection (fever, persistent sore throat), fast/irregular/pounding heartbeat, weakness, seizures, confusion, slurred speech, and severe headaches are all very infrequent, but severe unwanted effects. If they do arise, you should get immediate medical attention.
Contact your doctor if you notice other effects not listed above.
FocalinXR has all the same negative effects that Focalin has; the XR also includes heartburn, dizziness, dry mouth as a more common negative effect. 
The Focalin XR capsules are also a great choice for children because of their flexibility in usage and ingestion. As mentioned before, the capsules can be opened and their contents mixed with applesauce or pudding to help children who cannot swallow large capsules to acquire an alternate form of ingestion. This is due to the SODAS (Spheroidal Oral Drug Absorption System) delivery system, also used in Ritalin LA. These capsules also have a very convenient dosage plan. Doses come in five, ten, fifteen, and twenty milligram capsules. To determine the dosage that will be administered, one to four five milligram capsules are taken, and a treatment plan can be formulated based upon results and behavior. This is a good alternative for children, because there is a large variability of doses, and a plan can be chosen to make children more comfortable while taking medication.
Misuse and Illegal Usage
Focalin XR is also sold illegally on college campuses by other students for as little as $2 and as much as $7 per pill. Focalin increases concentration; it allows a student to study, without a break, for many hours. According to the University of Rochester, "between 4 and 25 percent of college students use or have used a prescription stimulant as a study aid".  .
- Amphetamine-- Adderall
- Atomoxetine-- Strattera
- Dextroamphetamine-- Dexedrine
- Methylphenidate-- Concerta, Ritalin
- Lisdexamfetamine-- Vyvanse
- Methamphetamine-- Desoxyn
- ↑ Arnold, L.E., et al. (2004). "A double-blind, placebo-controlled withdrawal trial of dexmethylphenidate hydrochloride in children with attention deficit hyperactivity disorder". J Child Adolesc Psychopharmacol. 2004 Winter;14(4):542-54.
- ↑ Keating, G.M. & Figgitt, D.P. (2002). "Dexmethylphenidate". Drugs. 2002;62(13):1899-904; discussion 1905-8.
- ↑ Teo, S.K., et al. (2004). "A Single-Dose, Two-Way Crossover, Bioequivalence Study of Dexmethylphenidate HCl with and without Food in Healthy Subjects". J Clin Pharmacol. 2004 Feb;44(2):173-8.
- ↑ McGough J.J., Pataki C.S., Suddath R. (2005). "Dexmethylphenidate extended-release capsules for attention deficit hyperactivity disorder". Expert Rev Neurother. 2005 Jul;5(4):437-41.
- ↑ Silva, R., et al. (2004). "Open-Label Study of Dexmethylphenidate Hydrochloride in Children and Adolescents with Attention Deficit Hyperactivity Disorder". J Child Adolesc Psychopharmacol. 2004 Winter;14(4):555-63.
- ↑ "Attention deficit disorder: Old questions, new answers ".
- ↑ "Oral Uses ".
- ↑ "Drug Treatments-Focalin ".
- ↑ "Focalin XR for ADHD ".
- ↑ "Prescription Stimulants"
- ↑ "Other campuses: Some students use drugs to focus on studying"
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