Dexmethylphenidate, sold under the brand name Focalin among others, is a
central nervous system
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...
(CNS)
stimulant
Stimulants (also known as central nervous system stimulants, or psychostimulants, or colloquially as uppers) are a class of drugs that increase alertness. They are used for various purposes, such as enhancing attention, motivation, cognition, ...
used in the treatment of
attention deficit hyperactivity disorder
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by symptoms of inattention, hyperactivity, impulsivity, and emotional dysregulation that are excessive and pervasive, impairing in multiple con ...
(ADHD) in those over the age of five years.
It is taken
by mouth
Oral administration is a route of administration whereby a substance is taken through the Human mouth, mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications.
Oral administ ...
.
[ The immediate-release formulation lasts up to five hours while the extended-release formulation lasts up to twelve hours. It is the more active ]enantiomer
In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...
of methylphenidate
Methylphenidate, sold under the brand names Ritalin ( ) and Concerta ( ) among others, is a central nervous system (CNS) stimulant used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. It may be taken Oral adm ...
.
Common side effects include abdominal pain
Abdominal pain, also known as a stomach ache, is a symptom associated with both non-serious and serious medical issues. Since the abdomen contains most of the body's vital organs, it can be an indicator of a wide variety of diseases. Given th ...
, loss of appetite
Anorexia is a medical term for a loss of appetite. While the term outside of the scientific literature is often used interchangeably with anorexia nervosa, many possible causes exist for a loss of appetite, some of which may be harmless, while o ...
, and fever
Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with Human body temperature, body temperature exceeding the normal range caused by an increase in the body's temperature Human body temperature#Fever, s ...
.[ Serious side effects may include ]psychosis
In psychopathology, psychosis is a condition in which a person is unable to distinguish, in their experience of life, between what is and is not real. Examples of psychotic symptoms are delusions, hallucinations, and disorganized or inco ...
, sudden cardiac death
Cardiac arrest (also known as sudden cardiac arrest ''SCA is when the heart suddenly and unexpectedly stops beating. When the heart stops beating, blood cannot properly circulate around the body and the blood flow to the brain and other org ...
, mania
Mania, also known as manic syndrome, is a Psychiatry, psychiatric Abnormality (behavior), behavioral syndrome defined as a state of Abnormality (behavior), abnormally elevated arousal, affect (psychology), affect, and energy level. During a mani ...
, anaphylaxis
Anaphylaxis (Greek: 'up' + 'guarding') is a serious, potentially fatal allergic reaction and medical emergency that is rapid in onset and requires immediate medical attention regardless of the use of emergency medication on site. It typicall ...
, seizures
A seizure is a sudden, brief disruption of brain activity caused by abnormal, excessive, or synchronous neuronal firing. Depending on the regions of the brain involved, seizures can lead to changes in movement, sensation, behavior, awareness, o ...
, and priapism.[ Safety during ]pregnancy
Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins.
Conception (biology), Conception usually occurs ...
and breastfeeding
Breastfeeding, also known as nursing, is the process where breast milk is fed to a child. Infants may suck the milk directly from the breast, or milk may be extracted with a Breast pump, pump and then fed to the infant. The World Health Orga ...
is unclear.
Dexmethylphenidate was approved for medical use in the United States in 2001. It is available as a generic medication
A generic drug is a pharmaceutical drug that contains the same chemical substance as a drug that was originally protected by chemical patents. Generic drugs are allowed for sale after the patents on the original drugs expire. Because the active ch ...
.[ In 2022, it was the 109th most commonly prescribed medication in the United States, with more than 5million prescriptions.
]
Medical uses
Dexmethylphenidate is used as a treatment for attention deficit hyperactivity disorder
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by symptoms of inattention, hyperactivity, impulsivity, and emotional dysregulation that are excessive and pervasive, impairing in multiple con ...
(ADHD), usually along with psychological, educational, behavioral or other forms of treatment. It is proposed that stimulants help ameliorate the symptoms of ADHD by making it easier for the user to concentrate, avoid distraction, and control behavior. Placebo-controlled trials have shown that once-daily dexmethylphenidate XR was effective and generally well tolerated.
Improvements in ADHD symptoms in children were significantly greater for dexmethylphenidate XR versus placebo.[ It also showed greater efficacy than osmotic controlled-release oral delivery system (]OROS
The osmotic-controlled release oral delivery system (OROS) is an advanced Time release technology, controlled release oral drug delivery system in the form of a rigid Tablet (pharmacy), tablet with a semi-permeable outer membrane and one or more ...
) methylphenidate over the first half of the laboratory classroom day but assessments late in the day favoured OROS methylphenidate.
Contraindications
Adverse effects
Products containing dexmethylphenidate have a side effect profile comparable to those containing methylphenidate.
Interactions
Pharmacology
Dexmethylphenidate has a 4–6 hour duration of effect. A long-acting formulation, Focalin XR, which spans 12 hours is also available and has been shown to be as effective as DL (dextro-, levo-)-TMP (threo-methylphenidate) XR (extended release) (Concerta, Ritalin LA), with flexible dosing and good tolerability. It has also been demonstrated to reduce ADHD symptoms in both children and adults. d-MPH has a similar side-effect profile to MPH and can be administered without regard to food intake.
CTx-1301 is an experimental medication that is an extended-release formulation of dexmethylphenidate that has a half life more than an hour longer than extended-release dexmethylphenidate (d-MPH-ER). It is under development for ADHD.
Mechanism of action
Methylphenidate is a catecholamine
A catecholamine (; abbreviated CA), most typically a 3,4-dihydroxyphenethylamine, is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine.
Cate ...
reuptake inhibitor that indirectly increases catecholaminergic neurotransmission by inhibiting the dopamine transporter
The dopamine transporter (DAT, also sodium-dependent dopamine transporter) is a membrane-spanning protein coded for in humans by the ''SLC6A3'' gene (also known as ''DAT1''), that pumps the neurotransmitter dopamine out of the synaptic cleft ba ...
(DAT) and norepinephrine transporter
The norepinephrine transporter (NET), also known as noradrenaline transporter (NAT), is a protein that in humans is encoded by the solute carrier family 6 member 2 (SLC6A2) gene.
NET is a monoamine transporter and is responsible for the sodium ...
(NET), which are responsible for clearing catecholamines from the synapse
In the nervous system, a synapse is a structure that allows a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or a target effector cell. Synapses can be classified as either chemical or electrical, depending o ...
, particularly in the striatum
The striatum (: striata) or corpus striatum is a cluster of interconnected nuclei that make up the largest structure of the subcortical basal ganglia. The striatum is a critical component of the motor and reward systems; receives glutamat ...
and meso-limbic system. Moreover, it is thought to "increase the release
Release may refer to:
* Art release, the public distribution of an artistic production, such as a film, album, or song
* Legal release, a legal instrument
* News release, a communication directed at the news media
* Release (ISUP), a code to i ...
of these monoamines into the extraneuronal space."
Although four stereoisomers
In stereochemistry, stereoisomerism, or spatial isomerism, is a form of isomerism in which molecules have the same molecular formula and sequence of bonded atoms (constitution), but differ in the three-dimensional orientations of their atoms i ...
of methylphenidate
Methylphenidate, sold under the brand names Ritalin ( ) and Concerta ( ) among others, is a central nervous system (CNS) stimulant used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. It may be taken Oral adm ...
(MPH) are possible, only the threo diastereoisomers are used in modern practice. There is a high eudysmic ratio between the SS and RR enantiomers
In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...
of MPH. Dexmethylphenidate (d-threo-methylphenidate) is a preparation of the RR enantiomer of methylphenidate. In theory, ''D''-TMP (d-threo-methylphenidate) can be anticipated to be twice the strength of the racemic
In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as r ...
product.
Notes
References
{{Portal bar , Medicine
Enantiopure drugs
Stimulants
2-Benzylpiperidines
Drugs developed by Novartis
Norepinephrine–dopamine reuptake inhibitors
Nootropics
Methyl esters
Methylphenidate
2-Piperidinyl compounds
Attention deficit hyperactivity disorder management
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