METHAMPHETAMINE
Meth
Methamphetamine Methamphetamine is a stimulant that produces a sense of euphoria and is an aphrodisiac similarly related to amphetamines but more potent and longer-lasting. Unlike amphetamine, it is directly toxic to dopamine neurons, with hyperthermiaaggravating its toxicity. It is highly addictive, with prolonged abuse capable of causing serious health problems, including depression, anhedonia, psychosis, Parkinson's disease and cardiac damage. In the United States the Dextro isomer, which is Schedule II, is prescribed under the brand name Desoxyn for narcolepsy and ADHD, although this is uncommon due to the stigma associated with the drug and the availability of alternatives. In contrast, the levo isomer is available over the counter as a component of Vicks Vapor Inhaler wherein it functions as a vasoconstrictor, with little if any effect on the central nervous system.
Methamphetamine or crystal meth as it is commonly known is a long acting, powerful and addictive stimulant closely related to amphetamine. Longer lasting and more toxic in its effects on the central nervous system than amphetamine itself, methamphetamine has a high potential to be abused and addiction. Methamphetamine is a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol and is taken orally, intra nasally (snorting the powder), by needle injection, or by smoking. Methamphetamine causes euphoria, increased wakefulness and physical activity and decreased appetite. Chronic, long-term use can lead to psychoticbehavior, hallucinations, stroke or heart attack.
Methamphetamine Methamphetamine is a stimulant that produces a sense of euphoria and is an aphrodisiac similarly related to amphetamines but more potent and longer-lasting. Unlike amphetamine, it is directly toxic to dopamine neurons, with hyperthermiaaggravating its toxicity. It is highly addictive, with prolonged abuse capable of causing serious health problems, including depression, anhedonia, psychosis, Parkinson's disease and cardiac damage. In the United States the Dextro isomer, which is Schedule II, is prescribed under the brand name Desoxyn for narcolepsy and ADHD, although this is uncommon due to the stigma associated with the drug and the availability of alternatives. In contrast, the levo isomer is available over the counter as a component of Vicks Vapor Inhaler wherein it functions as a vasoconstrictor, with little if any effect on the central nervous
INTRODUCTION TO METHAMPHETAMINE
Methamphetamine or crystal meth as it is commonly known is a long acting, powerful and addictive stimulant closely related to amphetamine. Longer lasting and more toxic in its effects on the central nervous system than amphetamine itself, methamphetamine has a high potential to be abused and addiction. Methamphetamine is a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol and is taken orally, intra nasally (snorting the powder), by needle injection, or by smoking. Methamphetamine causes euphoria, increased wakefulness and physical activity and decreased appetite. Chronic, long-term use can lead to psychoticbehavior, hallucinations, stroke or heart attack.
UsingMethamphetamine
Routes of administration
People generally have a preferred way of administering Methamphetamine, often favoured because of a desired higher bio-availability, and sometimes for the ritual(s) it involves
Smoking - Methamphetamine is smoked, either out of a glass pipe composed of a a bowl and stem, or off foil. This is the most common ROA due to high bio-availability (~90.3%) without the risks of injection, or the discomfort of insufflation or plugging.
Insufflation - Just as snorting most other substances, This produces a quick, but short-lived peak followed by a few hours of coasting. Many users report the effects of insufflation last much longer than smoking. The bio-availability is a surprisingly low ~79%.
Injection - This is a popular ROA among long time users for its quick intense rush and the 100% bio-availability. The risks of injecting street methamphetamine are very high. A regular user is at risk of developing pulmonary embolism (PE), a blockage of the main artery of the lung or one of its branches, and commonly develop skin rashes (also known as "speed bumps") or infections at the site of injection. One also risks putting "cut" into their veins when this is done.
Oral - This ROA is often used for its discreet nature. Users will sometimes empty Tylenol capsules and fill them with Methamphetamine for public use. This is the safest way to ingest methamphetamine, presenting the least amount of risk factors. The only common factor being the substance itself, not taking into consideration each person's individual risk factors. Oral bio-availability of methamphetamine is ~62.7.
Plugging - This is an uncommon ROA, due to the stigma associated with putting drugs into the rectum (outside medical contexts). Pluggingmethamphetamine involves inserting the druginto the anus (or vagina) directly, via capsule, or by dissolving it in water and using a hypodermic syringe with the needle removed to squirt the resulting methamphetamine solution into the rectum. Some users report increased sexual satisfaction with this method of administration. Methamphetamine will have a fairly easy onset with a high peak, a long coast and an easy comedown. The bio-availability of suppository methamphetamine use is ~99%
Effects of Methamphetamine
The typical effects of methamphetamine in low doses are improved mood or euphoria, increased alertness, wakefulness and concentration, increased sociability, creative stimulation (for example music, writing, art), decreased appetite, increased libido, feelings of confidence, freedom from care, and interest in even otherwise mundane things and activities. Large doses of methamphetamine have been observed to cause psychosis, rhabdomyolysis, cerebral hemorrhage, life-threatening hypothermia above 41°C, renal and liver failure, cardiac arrhythmia's, heart attacks, cerebrovascular hemorrhages, strokes and seizures.
As a black market substance methamphetamine is variable in its method of production and quality from one batch to another. Different types of crystal methamphetamine, and quality of crystal methamphetamine can greatly differ depending on country and even city of origin. This variability means the effects of methamphetamine are not going to be uniform. Methamphetamine can also provide different effects as a function of the route of administration used.
Since users of meth often stay awake for long periods of time, the effects experienced during the initial onset can be quite different from the effects experienced during the end of a methamphetamine binge.
Combinations with Methamphetamine
Methamphetamine should not be used with monoamine oxidase inhibitors (MAOIs) or for 14 days following their administration; taking them together may cause serious enough high blood pressure to result in serious organ damage. CYP2D6 inhibitors (e.g., selective serotonin reuptake inhibitors (SSRIs)) prolong the effects of methamphetamine by slowing its metabolism and thereby prolonging its half-life. Methamphetamine may decrease the effects of CNS depressants and increase the effects of stimulants and antidepressants. Methamphetamine may counteract the effects of anti-hypertensives and anti-psychotics. Methamphetamine absorption is pH-dependent, proton pump inhibitors, which reduce gastric acid, interact with methamphetamine to lengthen its half-life.
Different Uses for Methamphetamine
Methamphetamiine (as Desoxyn, methamphetamine hydrochloride tablets) is approved in the USA as an adjunct in treatment of Attention Deficit Disorder with Hyperactivity (a behavioral syndrome characterized by moderate to severe distractibility, short attention span, hyperactivity, impulsivity, and emotional instability, where all are severe enough to be problematic and inappropriate to the developmental stage of the child) in children 6 years or older. Therapeutic doses typically start at 5 mg once or twice a day, these then may be raised in increments of 5 mg until optimal effects are seen; the typical effective dose of methamphetamine for ADHD is 20 to 25 mg daily.
Methamphetamine (in the form of Desoxyn) is also approved in the USA for short-term treatment of obesity that is refractory (has not responded to) other treatments including diets, groups program's or other drugs. This treatment has been shown effective only for a matter of several weeks, methamphetamine's suppression of appetite being quickly subject to tolerance effects.
Pharmacology of Methamphetamine
LD50 (mg/kg) (as the hydrochloride)
Mice : 70 intraperitoneally
Methamphetamine is a sympathomimetic amine with stimulating effects in both the central and peripheral nervous system including elevation of systolic and diastolic blood pressures and weak bronchodilator and respiratory stimulant action. In humans, orally administered methamphetamine reaches peak blood levels 3-6 hours after ingestion. Methamphetamine is highly lipophilic it crosses the blood brain barrier and will cross the placenta to directly affect fetal tissues and nervous system. Methamphetamine is mainly metabolized in the liver by aromatic hydroxylation, N-dealkylation and deamination and has at least seven metabolites. The elimination half-life of methamphetamine is 10-12 hours. Methamphetamine excretion occurs mostly via urine and is dependent on urine pH, higher pH (alkaline) urine significantly increases methamphetamine half-life by reducing the rate of elimination. Close to two-thirds of an oral dosage is excreted in the urine within the first 24 hours with about two-thirds of that as metabolites and one-third as methamphetamine.
Once in the brain methamphetamine causes a cascading release of norepinephrine, dopamineand serotonin. Methamphetamine increases dopamine and serotonin release from storage vesicles (reverse transport) and blocks their uptake, thereby increasing their cytoplasmic concentrations and making them more readily available for reverse transport. The consequence of an acute dose of methamphetamine increase the neurotransmitters of norepinephrine, dopamineand serotonin.
Dangers of Methamphetamine
Physical Health RisksNeurotoxicityassociated enzymes, their receptors, and their transporters. Methamphetamine has also been shown to produce morphological signs of axonal degeneration, and morphological studies have suggested that the reductions of dopamine and serotonin markers are related to destruction of the axons and axon terminals but not the bodies of the neurons themselves. These neurotoxic effects of methamphetamine appear to be ambient and core body temperature dependent, with higher temperatures associated with greater damage.
Methamphetamine seems to most severely affect dopamine terminals in the striatum, and at most minimally damage dopamine terminals in the nucleus accumbens, olfactory bulb, frontal cortex, and hypothalamus, possibly because of differing densities of dopamine and its transmission in these brain regions. The damage methamphetamine does to serotoninterminals in various brain regions including hippocampus, prefrontal cortex, amygdala, and striatum appears to be of equal severity.
Heart-related problemsThere have been reports of increased blood pressure, increased heart rate, stroke and heart attack in adults, and sudden death in patients who have heart problems or heart defects with use of methamphetamine and other stimulants. Continual abuse of methamphetamine can also lead to coronary heart disease and cardiomyopathy.[17] People with heart problems, heart defects, high blood pressure or a family history of these should avoid use of methamphetamine and if prescribed desoxyn ensure their doctor knows of these.
Seizures and other neurological problemsSome reports have indicated that stimulant use can lower seizure thresholds in patients with a history of seizure, patients with EEG abnormalities, but no seizure, and, in rare cases, in patients with neither seizure history nor abnormal EEG. A lowered seizure threshold increases risk of seizure.[19] Amphetamineshave been reported to worsen motor and phonic tics in Tourette's syndrome.[20]
Circulation problems in fingers and toesThere have been reports of circulatory problems in the extremities (Peripheral vasculopathy, including Raynaud’s phenomenon) associated with the use of methamphetamine. Symptoms include numbness, cold, pain, and change in colour from pale to blue, to red in fingers and/or toes. Anyone experiencing these symptoms should seek medical attention.
SMOKED Dosage
>90%
< 5 mg
5 - 10 mg
10 - 20 mg
20 - 60 mg
60 mg +
1 - 3 hours
0 - 2 minutes
20 minutes
1 hour
2 - 3 hours
ORAL DOSAGE
< 5 mg
5 - 15 mg
15 - 30 mg
30 - 60 mg
60 - 150 mg +
8 - 12 hours
20 - 45 minutes
3 - 5 hours
3 - 4 hours
12 - 24 hours
Overdose
Methamphetamine overdoses typically cause restlessness, tremor, severely high blood pressure, hyperreflexia, rapid breathing, confusion, aggression, hallucinations, panic, hyperpyrexia, and rhabdomyolysis. After the stage of excessive central nervous system stimulation, fatigue and depression often occur. Overdose of methamphetamine can cause heart arrhythmias, high or low blood pressure, and circulatory collapse. Methamphetamine overdose also causes nausea, abdominal cramping, vomiting, and diarrhea. In cases of fatal poisoning death is typically preceded by convulsions and coma.
Reported DeathsFatalities have been reported associated with methamphetamine use, abuse and overdose. Methamphetamine related deaths often involve cardiovascular complications and these are more likely to occur with injection and smoking of methamphetamine than other routes of administration. In the majority of methamphetamine toxicity related death's other substances are also found to be present, most frequently opiates/opioids or benzodiazepines. Methamphetamine toxicity does not appear to have a clear dosage–response, methamphetamine toxicity related death is associated with both low or high levels of methamphetamine in the blood. Postmortem blood levels of methamphetamine in one study suggest that a fatally toxic dose is >150mg.[23] [24] Reports suggest methamphetamine-related deaths frequently involve multiple congestion, pulmonary oedema, pulmonary congestion, cerebrovascular haemorrhage due to high blood pressure, ventricular fibrillation, acute cardiac failure or hyperpyrexia. Methamphetamine deaths due to septic injection or asphyxia by aspiration of vomit have also been reported. A large proportion of methamphetamine-related fatalities arise from accidents, suicide and homicides, rather than physical causes directly attributable to methamphetamine toxicity. This suggesting toxic methamphetamine doses pose risk of severe psychological and behavioural disturbances.
Sudden deaths, fatal stroke, and hearts attacks have also been reported in adults taking stimulant drugs at usual doses for ADHD.
Mental Health RisksPsychosis, new or worsened mental illness and suicidal thinkingReports of new and increased mental illness and symptoms are associated with use of stimulantdrugs at regular prescribed doses, including aggressive behaviour and hostility, bipolar depression, mania, psychosis and psychoticsymptoms such as hallucinations (particularly auditory) and delusions. One study found that psychotic and manic symptoms in patients without a history of psychosis or mania were rare, happening at a rate of about one in 1000. Methamphetamine use by patients with bipolar disorder may worsen or trigger a manic episode. Use of methamphetamine by patients with a preexisting psychotic disorder can can increase and worsen their behavioural and thought disturbances.
Recreational use of methamphetamine typically involves higher than therapeutic doses and exhibits a pattern of bingeing, and hence is likely to present higher risk of psychotic or manic symptoms even in those with no history. Clinical data show that methamphetamine binges can result in psychosis, but it is not known whether this psychosis is purely the result of the amount ingested in a dose or over the binge, or due to a triggering of pre-existing vulnerability in some methamphetamine users, a combination of these, or the result of methamphetamine related sleep deprivation. Over 25% of those initially diagnosed with methamphetamine induced psychosis after some years developed a primary psychotic disorder, suggesting at least some cases may involve preexisting vulnerability. It has been demonstrated that amphetamines can trigger psychosis in healthy subjects given consecutively higher doses. Though psychosisdid not occur in 100% of subjects, it usually occurred after 100–300 mg of amphetamine. But studies indicate only a weak relationship between stimulant psychosis and blood levels of amphetamines.
Methamphetamine should be avoided by those with depression, bipolar illness, psychosis or a history of suicidal thinking or attempts. Any patient prescribed methamphetamine (desoxyn) with a history of depression, bipolar illness, psychosis or a history of suicidal thinking or attempts must ensure their doctor knows of it.
Cognitive impairmentSome studies have found that chronic recreational methamphetamine use is associated with a range of cognitive impairments, including deficits in attention, working memory, and decision-making.
