| Title |
Pharmacokinetics and Clinical Effectiveness of Methylphenidate
|
|---|---|
| Published in |
Clinical Pharmacokinetics, September 2012
|
| DOI | 10.2165/00003088-199937060-00002 |
| Pubmed ID | |
| Authors |
Hui C. Kimko, James T. Cross, Darrell R. Abernethy |
| Abstract |
Methylphenidate is prescribed for over 90% of children in the US diagnosed as having attention-deficit hyperactivity disorder (ADHD). Although ADHD has been widely studied, the use of methylphenidate in ADHD still poses a number of unresolved questions, including its pharmacodynamic characteristics (drug concentration-effect relationship) and the effect of long term treatment on the patient's psychopathology later in life. The objective of this review is to provide an analysis of the pharmacokinetic-pharmacodynamic properties and therapeutic effectiveness of methylphenidate that may help to answer some of these questions. Methylphenidate has 2 chiral centres, but the drug used in therapy comprises only the threo pair of enantiomers. d-threo-Methylphenidate is more potent than the l-enantiomer. Methylphenidate is administered as a racemic mixture that undergoes stereoselective clearance. Methylphenidate is a short-acting stimulant with a duration of action of 1 to 4 hours and a pharmacokinetic half-life of 2 to 3 hours. Maximum drug concentration after oral administration occurs at about 2 hours. Methylphenidate is absorbed well from the gastrointestinal tract and easily passes to the brain. Methylphenidate is efficacious for short term treatment for children with ADHD. Its mechanism of action is not understood, but may be associated with its influence on multiple neurotransmitters, especially the release and reuptake of dopamine in the striatum. There is marked individual variability in the dose-response relationship for methylphenidate, and therefore dosage must be titrated for optimal effect and avoidance of toxicity in each child. It is unclear whether this variability is predominantly pharmacokinetic or pharmacodynamic. If variable stereoselective metabolism occurs clinically, therapeutic drug monitoring of methylphenidate will require the application of chiral assay methods for the analysis of the active component, d-threo-methylphenidate. It is difficult to predict which children will have a favourable response to methylphenidate. Nonetheless, several studies have been published linking the severity of ADHD in children with improved clinical response to methylphenidate. The use of individual single-blind medication trials may be a practical solution to this problem. Additionally, the targeted condition warrants careful consideration, since different conditions (e.g. misbehaviour or poor academic performance) may require different regimens. Further studies of the relationship between the pharmacokinetic and pharmacodynamic properties of methylphenidate are required to allow the development of optimal dosage regimens. |
Mendeley readers
The data shown below were compiled from readership statistics for 286 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United Kingdom | 1 | <1% |
| Germany | 1 | <1% |
| Australia | 1 | <1% |
| Unknown | 283 | 99% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 56 | 20% |
| Student > Bachelor | 51 | 18% |
| Student > Ph. D. Student | 31 | 11% |
| Researcher | 30 | 10% |
| Student > Doctoral Student | 17 | 6% |
| Other | 30 | 10% |
| Unknown | 71 | 25% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 42 | 15% |
| Psychology | 35 | 12% |
| Agricultural and Biological Sciences | 30 | 10% |
| Neuroscience | 23 | 8% |
| Chemistry | 22 | 8% |
| Other | 49 | 17% |
| Unknown | 85 | 30% |
Attention Score in Context
This research output has an Altmetric Attention Score of 7. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 21 January 2024.
All research outputs
#5,339,368
of 25,374,917 outputs
Outputs from Clinical Pharmacokinetics
#346
of 1,602 outputs
Outputs of similar age
#38,004
of 187,199 outputs
Outputs of similar age from Clinical Pharmacokinetics
#120
of 450 outputs
Altmetric has tracked 25,374,917 research outputs across all sources so far. Compared to these this one has done well and is in the 78th percentile: it's in the top 25% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,602 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 6.1. This one has done well, scoring higher than 77% of its peers.
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We're also able to compare this research output to 450 others from the same source and published within six weeks on either side of this one. This one has gotten more attention than average, scoring higher than 72% of its contemporaries.