amphetamines
history
Chinese use stimulant ephedra (ma huang) containing the alkaloids ephedrine & pseudoephedrine for over 5000yrs to Rx asthma & URTI.
amphetamine 1st synthesised in Germany in 1887 but not used clinically until 1920's following reduced availability of ephedrine to Rx asthma.
-
nasal decongestant containing amphetamine marketed in 1932, but widespread abuse led to FDA banning amphetamine inhalers in 1959.
amphetamines were widely used as stimulants during World War II for a variety of conditions including hypotension & obesity.
passage of Controlled Substance Act in US in 1970 reduced rates of amphetamine abuse.
'designer' amphetamines created in 1980's for illicit recreational use including the more serotoninergic MDMA (Ecstasy).
resurgence of metamphetamine abuse due to production of high purity formulation known as 'ice'.
the rave scene of the 1990's brought widespread use of MDMA and ice to Europe, North America, and Australasia.
production of similar piperazine family drugs such as BZP (became a restricted substance in 2008) followed.
4-Bromo-2,5-dimethoxyamphetamine (2CB, MFT, “Nexus”) is a rave drug which produces relaxation, euphoria and altered perception but also severe arterial spasm which has resulted in report on one limb requiring amputation.
medicinal amphetamines may be abused:
pharmacology
amphetamines are derived from the CNS stimulants, phenylethylamines, and have structural similarities to adrenaline.
metamphetamine is easily made (although risk of explosions in home labs) through reduction of ephedrine or pseudoephedrine (hence limited OTC availability of these).
they are lipophilic weak bases with large Vd & not readily metabolised by MAO or COMT, thus have long durations of actions.
eliminated by hepatic biotransformation & urine pH-dependent renal excretion.
amphetamines are taken up into neuronal cells via neuronal monoamine reuptake transporters, and also act as a substrate for these transporters, resulting in transporter-mediated neurotransmitter release.
desired actions of amphetamine & metamphetamine (Speed/Ice) amongst those who use them recreationally are:
desired actions of MDMA (Ecstasy) which has more serotoninergic actions, amongst those who use them recreationally are:
euphoria, inner peace, social facilitation, heightened sexuality and disinhibition, mild hallucinogen effects
-
amphetamine
Amp, Bennies, Black beauties, Browns, Cranks, Fives, Goey, Hearts, Louee, Speed, Uppers, Whiz
mainly sympathomimetic actions with greater peripheral effects than metamphetamine
basic drug with pKa of 9.9, thus alkaline urine reduces excretion and increases half-life to ~20 hours, while acidic urine reduces half life to 5-6 hours
generally taken orally but can be inhaled vaporised, or snorted as a fine powder, or injected
iv injection produces marked euphoria, clear thinking but inefficient, often reptitious vigorous activity
effects may include:
tachycardia, severe anxiety, paranoia, hallucinations (“snow lights”),insomnia, weight loss, SOB, chest pain, hypertension,
acute myocardial infarction (AMI/STEMI/NSTEMI), hepatotoxicity, seizures, circulatory collapse
-
there is a rapid fall off in effects which enhances intense craving for the drug which rapidly leads to addiction
withdrawal (“crashing”) leads to long periods of sleep, hunger, extreme lethargy, depression, suicidality and anhedonia
dexamphetamine
lisdexamfetamine
mainly sympathomimetic actions, most potent cardiovascular effects of all amphetamines, greater CNS effects than amphetamine
results in a far higher brain dopamine level than other commonly abused substances
crystal meth is becoming the major pyschosocially destructive substance abuse epidemic
-
3,4-MDMA (ecstasy)
3,4-methylenedioxymetamphetamine
Adam, Bart Simpson, Clarity, Disco biscuits, Essence, E, Ecstasy, Love drug, Red and black, White dove, X, XTC
usually colourful tablets at 50-200mg per dose
most tablets sold in Australia are not actually MDMA but metamphetamine which is simpler to make, and often include contaminants such as cocaine, heroin, ketamine, codeine, paracetamol, ephedrine, pseudoephedrine, caffeine, benzodiazepines, antihistamines and LSD.
a more recent development is use of MDMA in powder form (“Molly”) as users perceive that it is more likely to be MDMA
users of MDMA in the dance scene are advised to take frequent rest breaks and sip water regularly to rehydrate
unwanted effects include jaw clenching, teeth grinding, anxiety, paranoia, confusion, hallucinations, bizarre behaviour, and possibly psychosis.
overdose can result in hypertension, tachycardia and hyperthermia, and may be fatal.
2,5-Dimethoxy-4-methylamphetamine
4-Bromo-2,5-dimethoxyamphetamine
2CB, MFT, Nexus
extremely potent hallucinogen producing marked psychoactive effects, euphoria, altered perception
used impregnated in paper as with LSD
piperazines: BZP & TFMPP
Bliss, BNZ, Bolts, Charge, Exodus, Frenzy, Goodstuff, Grins, Herbal Ecstasy, Herbal party pills, Jumps, Kandy, Legal ecstasy, Legal E, Legal X, Nemesis, Red Hearts, Silver bullet.
BZP inhibitis reuptake of dopamine & serotonin & stimulates peripheral alpha-2 receptors but exhibits lower potency than amphetamine.
seizures, vomiting, collapse, agitation, anxiety & confusion are common in toxicity.
TFMPP is more serotoninergic and produces affects similar to MDMA
Alpha-PVP ("flakka")
flakka, gravel, bath salts
a synthetic cathinone and is related to MDPV (both of which are pyrovalerones)
cathinone is the naturally occurring β-ketone amphetamine analogue found in the Catha edulis (the Khat plant)
pyrovalerone-cathinones are potent and selective dopamine and noradrenaline uptake blockers, but are not effective releasers of monoamines
hallucinatory effects are consistent with other serotonergic drugs such as MDMA or LSD
can be ingested, injected, insufflated, taken sublingually, and vaporized and inhaled
iv injection is the major risk for lethality
have a high abuse and addiction potential
euphoria and increased libido effects last 2-7hrs but “undesirable” effects can last hours to days
toxicity includes:
bizarre behavior which is often aggressive and violent, hallucinations, psychosis
excessive sympathetic stimulation
-
-
N-methoxybenzyl hallucinogenic drugs
eg. 25I-NBOMe, 25B-NBOMe, 25C-NBOMe, “Blue Batman”, “N-Bomb”
new psychedelic drugs, 1st brought to Australia in 2012
similar to LSD but act at a very low dose, in micrograms instead of milligrams
typical doses cause hallucinations and euphoria and can last for more than 12 hours.
harmful side affects include delirium, aggressive behaviour, self-harm, and paranoia, and risk of death (eg. believing one can fly or swim)
amphetamines.txt · Last modified: 2016/06/14 20:19 (external edit)