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Methylphenidate

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Also known as

Concerta, Methylin, Ritalin, Medikinet, Equasym XL, mph, smart pills, ritties, vitamin r, kiddie coke, skittles, smarties, diet coke

Classification

Stimulant

Overview

Methylphenidate is a psychostimulant drug approved for treatment of ADHD, postural orthostatic tachycardia syndrome, and narcolepsy. It may also be prescribed for off-label use in treatment-resistant cases of lethargy, depression, neural insult and obesity. It is similar in structure as amphetamines however only produce mild effects of amphetamines [1].

Street price

Currently, it is being sold for 50p to £1 per tablet [2],

Why take it?

Sought after effects

  • increased alertness,
  • euphoria,
  • increased motivation,
  • abundance of energy [3].

Undesired effects

  • increased body temperature,
  • tachycardia,
  • hypertension,
  • dehydration,
  • paranoia,
  • racing thoughts,
  • insomnia [3].

Dosage

Therapeutic

When prescribed medically it is used orally at dosages between 5 to 60 mgs [1],

Abuse

Oral

  • threshold 5 - 10 mg,
  • light 10 - 20 mg [4], 20 - 40 mgs [5],
  • common 20 - 50 mg [4], 40 - 60 mgs [5],
  • strong 50 - 80 mg [4], 60 - 80 mgs [5],
  • heavy 80 mg+ [4], 80 - 100 mgs + [5].

Insufflated

  • light 5 - 15 mg,
  • common 15 - 40 mg,
  • strong 40 - 60 mg,
  • heavy 60 - 75 mg + [5].

How long do its effects last?

Onset of effects

  • oral - 20 - 60 minutes [4], 30 - 120 minutes [5], [3].
  • insufflated - 5 - 15 minutes [5], [3].

Come up

  • oral - 20 - 60 minutes [4].

Peak

  • oral - 90 - 150 minutes [4].

Offset

  • oral - 1 - 2 hours [4].

Duration of effects

  • oral - 4 - 6 hours [4], [3].
  • insufflated - 1 hour [5], 2 - 5 hours [3],

After-effects

  • oral - 2 - 6 hours [4].
  • insufflated - 1 - 24 hours [5].

Pharmacology

Pharmacodynamics

Methylphenidate is a central nervous system stimulant used most commonly in the treatment of attention-deficit disorders in children and for narcolepsy. Methylphenidate also blocks the reuptake of norepinephrine and dopamine. Its mechanisms appear to be similar to those of dextroamphetamine. Furthermore, it is a racemic mixture comprised of the d- and l-threo enantiomers. The d-threo enantiomer is more pharmacologically active than the l-threo enantiomer [6].

Pharmacokinetics

The pharmacokinetics of the methylphenidate capsule (CD) methylphenidate hydrochloride formulation have been studied in healthy adult volunteers and in children with ADHD [7],

Metabolism

Methylphenidate is hepatically metabolised. More specifically, it is rapidly and extensively metabolised by carboxylesterase CES1A1. Via this enzyme, methylphenidate undergoes de-esterification to ritalinic acid (a-phenyl-2-piperidine acetic acid, PPAA), which has little to no pharmacologic activity [6].

Half-life

d-methylphenidate = 3 - 4 hours; l-methylphenidate = 1 - 3 hours; Ritalinic acid = 3 - 4 hours [6].

Elimination

After oral administration of an immediate release formulation of methylphenidate, 78% - 97% of the dose is excreted in the urine and 1% - 3% in the faeces in the form of metabolites within 48 - 96 hours. Only small quantities (<1%) of unchanged methylphenidate appear in the urine. Most of the dose is excreted in the urine as ritalinic acid (60% - 86%), the remainder being accounted for by minor metabolites [6].

Lethal dosage

The LD50 of methylphenidate in rats is 190mg/kg. In humans it is estimated to be 250mg+ for a 75kg (130lb) person [3].

Mechanism of action

Methylphenidate is a norepinephrine and dopamine reuptake inhibitor. It inhibits the Dopamine Transporter enzyme that pumps out dopamine from a synapse for reuse, this leads to increased activation of dopamine receptors. It has a similar effect on the norepinephrine transporter. The latter is responsible for it's feelings of energy and bodily stimulation, whilst the former accounts for euphoria [1]. Methylphenidate blocks dopamine uptake in central adrenergic neurons by blocking dopamine transport or carrier proteins. Methylphenidate acts at the brain stem arousal system and the cerebral cortex and causes increased sympathomimetic activity in the central nervous system. Alteration of serotonergic pathways via changes in dopamine transport may result [6].

Signs of usage

  • abnormal movements (similar to tourette's),
  • agitation and anxiety,
  • altered sexual desire,
  • chest pain,
  • difficulty breathing,
  • dilated pupils,
  • dizziness,
  • general nervousness,
  • gastrointestinal distress,
  • hallucinations,
  • headaches,
  • nausea and vomiting,
  • OCD-like syndrome,
  • social withdrawal,
  • thoughts of suicide [8],

Effects

Short-term effects

  • excitation,
  • formication,
  • facial flushing,
  • perseveration [8],
  • wakefulness,
  • exhilaration,
  • agitation,
  • headache,
  • muscle twitches,
  • dilated pupils,
  • dry mouth,
  • sweating,
  • increased heart rate and body temperature,
  • nausea [9].

Long-term effects

  • delusions,
  • grandiosity,
  • hallucinations,
  • mania,
  • paranoia,
  • suicidal thoughts,
  • violence [8].

Physical effects

  • stimulation,
  • appetite suppression,
  • dehydration,
  • increased heart rate,
  • increased perspiration,
  • teeth grinding [4].

Cognitive effects

  • anxiety,
  • cognitive euphoria,
  • depression,
  • irritability,
  • time distortion,
  • analysis enhancement,
  • focus enhancement,
  • increased music appreciation,
  • memory enhancement,
  • motivation enhancement,
  • thought acceleration,
  • thought organisation,
  • wakefulness,
  • cognitive fatigue,
  • motivation suppression,
  • thought deceleration [4].

After effects

  • anxiety,
  • cognitive fatigue,
  • depression,
  • irritability,
  • motivation suppression,
  • thought deceleration,
  • wakefulness [4].

Minor effects

More common

  • abdominal or stomach pain,
  • headache,
  • loss of appetite,
  • nervousness,
  • stuffy nose,
  • trouble sleeping,
  • unusually warm skin [7].

Less common

  • anger,
  • decreased appetite,
  • dizziness,
  • drowsiness,
  • fear,
  • irritability,
  • muscle aches,
  • nausea,
  • runny nose,
  • scalp hair loss,
  • talking, feeling, and acting with excitement,
  • vomiting [7].

Major effects

More common

  • fast heartbeat [7].

Less common

  • chest pain,
  • fever,
  • joint pain,
  • skin rash or hives [7].

Rare

  • black, tarry stools,
  • blood in the urine or stools,
  • blurred vision or other changes in vision,
  • convulsions,
  • crusting, dryness, or flaking of the skin,
  • muscle cramps,
  • pinpoint red spots on the skin,
  • scaling, severe redness, soreness, or swelling of the skin,
  • uncontrolled vocal outbursts,
  • uncontrolled tics,
  • unusual bleeding or bruising [7].

Incidence not known

  • confusion,
  • depression,
  • feeling like surroundings are not real,
  • jaundice,
  • numbness of the hands,
  • painful or difficult urination,
  • pale skin,
  • paleness or cold feeling in the fingertips and toes,
  • red, irritated eyes,
  • red, swollen, or scaly skin,
  • seeing, hearing, or feeling things that are not there,
  • severe or sudden headache,
  • shortness of breath,
  • sores, ulcers, or white spots on the lips or in the mouth,
  • sudden loss of coordination,
  • sudden slurring of speech,
  • tingling or pain in the fingers or toes when exposed to cold,
  • unusual behaviour,
  • unusual tiredness or weakness,
  • weight loss [7].

Abuse

Positive

  • increased alertness,
  • euphoria,
  • increased motivation,
  • abundance of energy [3].

Neutral

  • reduced appetite,
  • flushing of the face [3].

Negative

  • increased body temperature,
  • tachycardia,
  • hypertension,
  • dehydration,
  • paranoia,
  • racing thoughts,
  • insomnia [3].

Coming down

  • irritability,
  • paranoia,
  • anxiety [9].

Overdose

  • vomiting,
  • agitation,
  • uncontrollable shaking of a part of the body,
  • muscle twitching,
  • seizures,
  • loss of consciousness,
  • inappropriate happiness,
  • confusion,
  • hallucinating,
  • sweating,
  • flushing,
  • headache,
  • fever,
  • fast, pounding, or irregular heartbeat,
  • widening of pupils,
  • dry mouth or nose [10],
  • euphoria,
  • delirium,
  • hyperpyrexia,
  • tachycardia,
  • palpitations,
  • cardiac arrhythmias,
  • hypertension [6].

Dangerous interactions

Although many drugs are safe on their own, they can become dangerous and even life-threatening when combined with other substances. The list below contains some common potentially dangerous combinations, but may not include all of them. Certain combinations may be safe in low doses of each but still increase the potential risk of death. Independent research should always be done to ensure that a combination of two or more substances is safe before consumption [4].

  • 25x-NBOMe - Both the NBOMe series and this compound induce powerful stimulation and their interaction may cause severe side-effects. These can include thought loops, seizures, increased blood pressure, vasoconstriction, increased heart rate, and heart failure (in extreme cases).
  • Alcohol - It is dangerous to combine alcohol, a depressant, with stimulants due to the risk of excessive intoxication. Stimulants decrease the sedative effect of alcohol which is the main factor most people consider when determining their level of intoxication. Once the stimulant wears off, the effects of alcohol will be significantly increased, leading to intensified disinhibition as well as respiratory depression. If combined, one should strictly limit themselves to only drinking a certain amount of alcohol per hour.
  • DXM - This combination may cause increased heart rate and panic attacks.
  • MXE - Increased heart rate and blood pressure may occur.
  • Tramadol - This combination can increase the risk of seizures.
  • MDMA - The neurotoxic effects of MDMA may be increased when combined with other stimulants.
  • MAOIs - This combination may increase the amount of neurotransmitters such as dopamine to dangerous or even fatal levels. Examples include syrian rue, banisteriopsis caapi, 2C-T-2, 2C-T-7, αMT, and some antidepressants [11].
  • Cocaine - This combination may increase strain on the heart [4].

Dangerous

  • αMT,
  • Tramadol - Tramadol and stimulants both increase the risk of seizures.
  • MAOIs - MAO-B inhibitors can increase the potency and duration of phenethylamines unpredictably. MAO-A inhibitors with amphetamine can lead to hypertensive crises [5],

Unsafe

  • DOx - The combined stimulating effects of the two can lead to an uncomfortable body-load, while the focusing effects of amphetamine can easily lead to thought loops. Coming down from amphetamines while the DOx is still active can be quite anxiogenic.
  • NBOMes - Amphetamines and NBOMes both provide considerable stimulation. When combined they can result in tachycardia, hypertension, vasoconstriction and in extreme cases heart failure. The anxiogenic and focusing effects of stimulants are also not good in combination with psychedelics as they can lead to unpleasant thought loops. NBOMes are known to cause seizures and stimulants can increase this risk.
  • 2C-T-x - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences. In extreme cases, they can result in severe vasoconstriction, tachycardia, hypertension, and in extreme cases heart failure.
  • 5-MeO-xxT - The anxiogenic and focusing effects of stimulants increase the chance of unpleasant thought loops. The combination is generally unnecessary because of the stimulating effects of psychedelics.
  • DXM - Both substances raise heart rate, in extreme cases, panic attacks caused by these drugs have led to more serious heart issues.
  • PCP - This combination can easily lead to hypermanic states [5],

Withdrawal

  • aggression,
  • anxiety,
  • depression,
  • hunger,
  • inability to concentrate,
  • hypersomnia,
  • mood swings,
  • paranoia [8].

Drug testing

The timetable for detecting MethylPhenidate in the system is also dependent upon each individual's metabolism, body mass, age, hydration level, physical activity, health conditions and other factors, making it almost impossible to determine an exact time MethylPhenidate will show up on a drug test [10].

The following is an estimated range of times, or detection windows, during which MethylPhenidate can be detected by various testing methods -

How long does methylphenidate stay in the urine?

MethylPhenidate can be detected in the urine for 1 - 2 days [10].

How long can methylphenidate be detected in blood?

There is currently no data available concerning the detection of MethylPhenidate in blood tests [10].

How long can a saliva test detect methylphenidate?

A saliva test can detect MethylPhenidate for up to 1 - 2 days [10].

How long can a hair test detect methylphenidate?

MethylPhenidate, like many other drugs, can be detected with a hair follicle drug test for up to 90 days [10].

Harm reduction

  • abuse or binging on methylphenidate can lead to heavy comedown effects which can, in extreme cases, result in psychosis. Get some sleep every night,
  • methylphenidate has been shown to be habit-forming, take care with repeated use,
  • drinking of alcohol (ethanol) also increases the blood plasma levels of d-methylphenidate by up to 40% [3].

As with all stimulants, remain hydrated and stay healthy [3].

History

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' [3].


References

  1. 1.0 1.1 1.2 Methylphenidate, 2013, http://wiki.bluelight.org/index.php/Methylphenidate
  2. Wren, A., Misusing prescription drugs, 2015, http://www.themix.org.uk/drink-and-drugs/drugs-and-your-body/misusing-prescription-drugs-9575.html
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 Methylphenidate, 2017, https://wiki.tripsit.me/wiki/Methylphenidate
  4. 4.00 4.01 4.02 4.03 4.04 4.05 4.06 4.07 4.08 4.09 4.10 4.11 4.12 4.13 4.14 Methylphenidate, 2017, https://psychonautwiki.org/wiki/Methylphenidate
  5. 5.00 5.01 5.02 5.03 5.04 5.05 5.06 5.07 5.08 5.09 5.10 Methylphenidate, 2017, http://drugs.tripsit.me/methylphenidate
  6. 6.0 6.1 6.2 6.3 6.4 6.5 Methylphenidate, 2017, https://www.drugbank.ca/drugs/DB00422
  7. 7.0 7.1 7.2 7.3 7.4 7.5 7.6 Methylphenidate, 2017, https://www.drugs.com/methylphenidate.html
  8. 8.0 8.1 8.2 8.3 Lautieri, A., Methylphenidate Abuse, 2017, http://drugabuse.com/library/methylphenidate-abuse/
  9. 9.0 9.1 Ritalin (an overview of abuse, addiction, signs, symptoms, treatment), 2016, https://www.addictions.com/ritalin-an-overview-of-abuse-addiction-signs-symptoms-treatment/
  10. 10.0 10.1 10.2 10.3 10.4 10.5 How Long Does MethylPhenidate Stay in Your System?, 2016, https://www.verywell.com/how-long-does-methylphenidate-stay-in-your-system-80285
  11. Gillman, P. K., Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity, British Journal of Anaesthesia, 2005, 95, 4, 434-441, https://doi.org/10.1093/bja/aei210, https://www.ncbi.nlm.nih.gov/pubmed/16051647