Methylphenidate was first synthesised by the Ciba Pharmaceutical Company in 1944, and after human testing which began in 1954 it first became available in 1957 under the brand name 'Ritalin' - marketed as a treatment for several conditions including chronic fatigue, depression and narcolepsy.
In the 1960s it was popularly used to reverse the effects of a barbiturate overdose, meanwhile also being sold in combination with other substances in 'health tonics' - the most notable of which being 'Ritonic.'
It was researched as a treatment option for ADD during its initial inception as a medically accepted condition, and has been available on a prescription-basis for this purpose since.
Today methylphenidate is available in instant release and extended release form and also as transdermal patch (Daytrana).
As mentioned above, Methylphenidate is in wide use worldwide for the treatment of ADHD - along with Adderall it is one of the most commonly prescribed chemicals.
The drug is also widely used off-prescription, by users seeking euphoria or surplus energy and concentration. Similar to Adderall It is commonly used by students at exam-times or for other study, often sold at a premium by colleagues with prescriptions.
Dosages from TripSit Factsheets
Note: Duration can be significantly longer with higher doses.
Note: The prevalence of negative effects increases with higher doses.
As with all stimulants, remain hydrated and stay healthy. See Stimulant Harm Reduction for more information.
See the Drug combinations chart for more information.
Methylphenidate primarily acts as a dopamineA neurotransmitter associated with movement, attention, learning, and the brain’s pleasure and reward system.-norepinephrine reuptake inhibitor (NDRINorepinephrine-Dopamine Reuptake Inhibitor) and also as a sigma-1 receptor agonistA substance that initiates a physiological response when combined with a receptor..
Four isomers of methylphenidate are known to exist. One pair of threo isomers and one pair of erythro are distinguished, from which only d-threo-methylphenidate exhibits the pharmacologically usually desired effects.
The dextrorotary enantiomers are significantly more potent than the levorotary enantiomers, and some medications therefore only contain dexmethylphenidate (such as Focalin).
Methylphenidate taken orallyRoute of administration in which the subject swallows a substance. has a bioavailabilityThe fraction of an administered dose that is absorbed into a living system. of 11–52%. The half-life of methylphenidate is 2–3 hours, depending on the individual. The peak plasma time is achieved at about 2 hours.
The LD50The dosage of a substance at which 50% of the exposed subjects does not survive. To estimate the LD50 for humans, tests are conducted on non-human subjects. of methylphenidate in rats is 190mg/kg. In humans it is estimated to be 250mg+ for a 75kg (130lb) person.