Dexmethylphenidate: Characteristics And Side Effects
Dexmethylphenidate is an isomer of methylphenidate, a medication used to treat children with ADHD. This variant of the well-known stimulant drug seems to work better than the original and its use seems to be spreading.
In this article we explain what dexmethylphenidate is and what effects it has, what its mechanism of action is, what adverse effects and interactions must be taken into account, and what role it plays in addiction and dependence.
What is dexmethylphenidate and what effects does it have?
Dexmethylphenidate or d-threo-methylphenidate is an isomeric variant of methylphenidate, a drug commonly used in people who suffer from attention deficit hyperactivity disorder (ADHD).
There are two isomers of methylphenidate: d-threo-methylphenidate and l-threo-methylphenidate, two compounds that differ, with respect to the original molecule, by small adjustments in the molecular chemical structure, which results in some properties of the drug are different. Apparently, only d-threo-methylphenidate would be the clinically active ingredient.
In Spain, the variant of methylphenidate that is marketed is the mixture of the two isomers, the racemic mixture (d,l)-threo-methylphenidate. However, in other countries the dexmethylphenidate variant is already being used, which would exclusively provide the therapeutic psychostimulant effects avoiding unwanted cardiovascular and anorectic effects (appetite suppressants) and reducing the potential for abuse of the substance.
This variant of methylphenidate It is marketed under the name Focalin and, like its analogue, it is used to treat individuals suffering from ADHD (from 5 years of age). Normally, if no benefit is observed after 4 weeks of consumption, it is usually discontinued.
The effects of dexmethylphenidate last between 4 to 6 hours (except for the long-acting formulation, which lasts up to 12 hours).
Mechanism of action
Although the mechanism of action of dexmethylphenidate is not completely clarified, it is suggested that it exerts its effect by amplifying the dopaminergic signal by blocking its reuptake at the presynaptic level.
This drug It would also be able to block the reuptake of another neurotransmitter, norepinephrine, joining its specific transporter. The general effect is an increase in the subject’s level of attention and alertness. This can be measured with devices that capture low voltage waves.
On the other hand, dexmethylphenidate increases the excitatory mechanisms of the brain, improving concentration, motor coordination and impulse control in the subject. In patients with ADHD, the effects of dexmethylphenidate are attributed to the ability of this drug to improve the inhibitory mechanisms of the fronto-subcortical circuits in which dopamine intervenes.
The compound would exert a regulatory action on the frontal cortex and subcortical structures, like the ventral part of the striatum, in the basal ganglia. This brain area also contains the nucleus accumbens, a structure in which dopamine would act by limiting the processing of the information to be processed, with the consequent improvement in the focusing of the subject’s attention.
Side effects
In general, although a drug like dexmethylphenidate is tolerated quite well, it does side effects may be observed at the beginning of treatment (as occurs with classic methylphenidate), although they are usually transient. Sometimes delaying or reducing the ingested dose may be enough to reduce adverse reactions.
The patient may suffer abdominal pains, changes in blood pressure and heart rate, and even nervous tics (the risk, in this sense, is minimal). However, studies indicate that side effects are mild and limited.
Some studies had postulated a possible relationship between the consumption of methylphenidate and a suppression in the secretion of growth hormone and prolactin. However, currently this relationship has already been rejected, since childhood patients treated with the drug would recover their normal height in adolescence.
However, the consumption of dexmethylphenidate can cause a series of side effects that should be noted:
Interactions with other medications
People who are being treated with dexmethylphenidate should take into account possible interactions with other types of medications. It is very important to always follow the guidelines indicated by the health professional reference.
We’ll see now some of the drugs that are contraindicated if you are being treated with dexmethylphenidate:
Addiction and dependence
Methylphenidate is a stimulant drug with a certain power of addiction and dependence, similar to what amphetamine can have For this reason, the consumption of this type of substance can generate dependence, both physical and psychological, which is more likely when dexmethylphenidate is used in high doses or as a recreational drug.
When used above the medical dosage range, stimulants can trigger psychosis processes, especially in predisposed people. With the consumption of almost all drugs with addictive potential, a protein called FosB is activated, which is part of the brain reward circuit (in the nucleus accumbens).
This protein combines with others and binds to receptors that promote the expression of certain neuronal genes that, in turn, modify the expression and activity of other neuronal groups, potentially generating epigenetic changes (genetic expression would be altered by the addition of certain molecules to DNA).
In several studies, dexmethylphenidate has shown benefits as replacement therapy for people with methamphetamine addiction and dependence Additionally, methylphenidate and amphetamines have also been investigated as a chemical replacement to treat people with cocaine addiction, in the same way that methadone is used as a replacement drug for physical dependence on heroin.
