Methylphenidate (also known as Concerta, Methylin, Ritalin, among others) is stimulant substance of the phenethylamine class. Methylphenidate is the parent compound of the substituted phenidates, a family of compounds that includes ethylphenidate, isopropylphenidate, and others. It acts primarily by enhancing the activity of the neurotransmitters dopamine and norepinephrine in the brain.
Methylphenidate was first licensed by the U.S. Food and Drug Administration (FDA) in 1955 for treating what was then known as “hyperactivity.” Although it was prescribed to patients as early as 1960, it only became heavily prescribed in the 1990s when the diagnosis of ADHD itself became more widely accepted..
Methylphenidate is approved for treatment of attention-deficit hyperactivity disorder (ADHD) and narcolepsy. It is often used by students with or without ADHD to enhance their mental abilities, improve their concentration, and help them study.
Methylphenidate is a synthetic molecule of the substituted phenethylamine class. It contains a phenethylamine core featuring a phenyl ring bound to an amino (-NH2) group through an ethyl chain. It is structurally similar to amphetamine, featuring a substitution at Rα which is incorporated into a piperidine ring ending at the terminal amine of the phenethylamine chain. Additionally, it contains a methyl acetate bound to R2 or its structure.
Methylphenidate is a chiral compound, presumably produced as a racemic mixture. It has an enantiopure also sold as a pharmaceutical; the dextrorotary enantiopure is known as “dexmethylphenidate” and is commonly sold as Focalin and Focalin XR.
Methylphenidate primarily acts as a dopamine–norepinephrine reuptake inhibitor. It is most active at modulating levels of dopamine and, to a lesser extent, norepinephrine.. Methylphenidate binds to and blocks dopamine transporters and norepinephrine transporters..
While both amphetamine and methylphenidate are dopaminergic, it should be noted that their methods of action are somewhat distinct. Specifically, methylphenidate is a dopamine reuptake inhibitor while amphetamine is both a releasing agent and reuptake inhibitor of dopamine and norepinephrine. Each of these drugs have a corresponding effect on norepinephrine which are weaker than their effects on dopamine. Methylphenidate’s mechanism of action at dopamine-norepinephrine release is still debated, but is fundamentally different from most other phenethylamine derivatives as methylphenidate is thought to increase general firing rate, whereas amphetamine reduces firing rate and reverses the flow of the monoamines via TAAR1 activation...
|Light||10 – 20 mg|
|Common||20 – 40 mg|
|Strong||40 – 60 mg|
|Heavy||60 mg +|
|Total||4 – 6 hours|
|Onset||20 – 60 minutes|
|Come up||20 – 60 minutes|
|Peak||1.5 – 2.5 hours|
|Offset||1 – 2 hours|
|After effects||2 – 6 hours
- Anxiety – Anxiety is reported with slightly more frequency than other common stimulants like amphetamine or cocaine.
- Cognitive euphoria – Compared to other stimulants such as amphetamine, this effect is mild but occasionally occurs at higher or non-orally administered doses.
- Ego inflation
- Emotion suppression – This is typically most intense at light and common doses, and is more commonly reported from medical usage rather than recreational.
- Focus enhancement – This component is most effective at low to moderate dosages as anything higher will usually impair concentration.
- Memory enhancement – Therapeutic doses of methylphenidate improve performance on working memory tests both in normal functioning individuals and those with ADHD..
- Time distortion – This can be described as the experience of time speeding up and passing much quicker than it usually would when sober.
- Thought acceleration
- Thought organization
- Analysis enhancement
- Motivation enhancement
- Suggestibility suppression
- Increased music appreciation – In comparison to other common stimulants such as amphetamine or cocaine, this effect is reported to be relatively mild or present only at higher doses.
- Compulsive redosing – Compulsive redosing is reported but with less frequency than other common stimulants such as amphetamine or cocaine, and typically at high or non-orally administered doses.