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SCOTTISH ADVISORY COMMITTEE ON DRUG MISUSE: Psychostimulant Working Group Report
CHAPTER 5: MODES AND ADVERSE EFFECTS OF USE
5.1 It is clear from the evidence available to the Working Group from medical literature, service providers and users that there is a wide range of potential physical and mental health problems resulting from psychostimulant use (see table in
Annex B). Many of these are serious and potentially fatal.
5.2 General health problems are associated with dependence on psychostimulants partly because nutrition is impaired resulting in increased susceptibility to illness and infection. In addition, heavy users show progressive social and occupational deterioration. The health consequences of psychostimulant use are further compounded by the abuse of other substances such as alcohol and heroin.
5.3 Neuro-psychological tests on chronic psychostimulant users show cognitive impairments that may impair the ability to make decisions and so adversely affect the outcome of treatment.
AMPHETAMINES
Modes of Use
5.4 Amphetamines are a group chemically related synthetic stimulant drugs generally produced illicitly or as tablets legally produced by pharmaceutical firms and subsequently diverted onto the illicit market. With a reduced availability of pharmaceutically produced amphetamine, it is now the illicitly produced form, of variable and often low purity, which is primarily available and abused. There are three basic types of amphetamines; laevoamphetamine, dextroamphetamine and methylamphetamine. The most widely available form on the black market is a white crystalline powder containing both laevoamphetamine and dextroamphetamine in equal proportions. It is commonly called as amp, speed, whizz or sulph.
5.5 The main routes of use are oral and intravenous although the drug can be taken nasally or, as an amphetamine base, smoked. The oral route is the commonest for both pharmaceutical and illicit amphetamines. The amphetamine sulphate powder is usually taken wrapped in a cigarette paper (called a "bomb") or by licking it off a finger dabbed into a bag of powder ("dabbing"). For injection, the amphetamine powder is dissolved in water and filtered through cotton wool or a cigarette filter to remove the larger particles prior to intravenous injection. The onset of action is much faster when injected than ingested (the "rush"). Nasal inhalation or "snorting" involves chopping the amphetamine sulphate into a fine powder and sniffing it through the nose. The onset of action is between that of injecting and swallowing. While methylamphetamine hydrochloride can be taken by the above routes, crystalline methylamphetamine base ("ice") can be smoked or injected. When smoked, it gives a "rush" similar to that of cocaine but with a longer duration of the euphoric state. Its use is currently relatively rare in Scotland.
5.6 The frequency of the drug use varies considerably. "Recreational" use is relatively common with individuals taking the drug only occasionally (often "snorting") or regularly but not daily (more often taking it orally). This is often in association with social activities and includes weekend use. Heavy and intermittent use or bingeing also occurs in amphetamine use, lasting hours or days, ending with the "crash" and subsequent withdrawal phase. At the severe end of the spectrum is the daily dependent user who usually takes the drug orally or intravenously.
5.7 As tolerance to the effects of amphetamine develops the dosage taken increases to achieve the same effect. There is some evidence to suggest that stimulant users may take sedative drugs such as diazepam or heroin to counter the stimulant effects of amphetamine at the end of a session of using the drug.
Physical health problems associated with amphetamine misuse
5.8 Amphetamines can cause a variety of cardiovascular problems. These include rapid heart rate, irregular heartbeat, increased blood pressure, and irreversible, stroke-producing damage to small blood vessels in the brain. Hyperthermia (elevated body temperature) and convulsions occur with high doses of amphetamine and can result in death. With an elevation in the blood pressure a stroke, which may be fatal or leave permanent disability, may occur.
5.9 Intravenous use can result in cellulitis, abscesses, septicaemia, arterial thrombosis, endocarditis (a chronic infection of the inner lining of the heart and heart valves), renal infarction, and thrombophlebitis. Sharing of injecting equipment raises the risks of contracting hepatitis B and C, HIV and ultimately AIDS.
5.10 Acute lead poisoning is another potential risk for amphetamine users. A common method of illegal amphetamine production uses lead acetate as a reagent. Production errors may therefore result in amphetamine contaminated with lead.
Psychiatric problems associated with amphetamine misuse
5.11 Episodes of anxiety and panic are common with repeated amphetamine abuse. Following a binge on amphetamines the individual enters the "crash" phase with depressive symptoms, agitation, anxiety, low energy and craving. Insomnia is prominent early on and may result in the individual using a sedative drug like alcohol, benzodiazepines or opiates to "come down" and this may be followed by a period of hypersomnia.
5.12 With chronic or high dose consumption of amphetamines, paranoid ideation may develop. An amphetamine psychosis may develop as the paranoid ideation becomes delusional in intensity and the individual believes themselves to be persecuted. Hyper-reactivity to stimuli may develop as may hallucinations. The individual may develop stereotyped behavioural patterns involving repetitive meaningless motor activities. Ultimately confusion, severe anxiety with a fugue like state may develop and sudden acts of violence may occur. Psychotic symptoms usually resolve over a few days following stopping the drug use, but may be more persistent.
5.13 Heavy chronic users also often show progressive social and occupational deterioration.
COCAINE
Modes of Use
5.14 Pharmaceutically produced cocaine is still used in medical practice to reduce local blood flow in some surgical interventions. Such use is, however, rare and the amounts produced and thus available for diversion are so small that this source of the pure drug can be effectively ignored. Abused cocaine is thus acquired from illicit manufactured sources.
5.15 There are two basic types of cocaine. Cocaine hydrochloride and cocaine alkaloid ("freebase" or "crack"). These varieties differ in their chemical structure and properties facilitating different modes of use. Cocaine hydrochloride is a white powder which is water soluble and the can be absorbed through the mucus membranes. This variety is broken down in the body to a significant extent when swallowed and is largely destroyed by burning (~1% surviving). It is thus taken nasally or intravenously. Cocaine alkaloid is not readily soluble in the mucous membranes or blood but has a low melting point and is easily volatised with lesser destruction (~80% surviving) and is thus generally taken by inhalation of the smoke given off when the drug is heated, usually in a pipe. This method of use gives the most pronounced effects.
5.16 "Freebasing" is the process whereby the user heats cocaine hydrochloride powder with an alkali such as sodium bicarbonate to "free" the cocaine alkaloid "base" from the salt. Alternatively cocaine hydrochloride can be mixed ("washed) with ammonia and the resulting precipitate dried. Adding ether to the mixture with ammonia is less commonly employed by users preparing the freebase from cocaine hydrochloride but may be used in the preparation of "crack" for distribution. The name "crack" derives from the sound the "rocks" of cocaine make as they are heated to be smoked.
5.17 Some users attempt to recycle cocaine from crack pipes. After a pipe has been used for a period of time residues of cocaine build up on the pipe. Some users recycle this so that it can be smoked. There are two ways of doing this:
5.18 The frequency of cocaine use varies considerably. "Recreational" use is relatively common with individuals taking the drug only occasionally (often "snorting"). This is often in association with social activities and includes weekend use. Daily use occurs as does heavy and intermittent use or "bingeing". Binges tend to take the form of repeated dosing with the drug, often in escalating amounts over a period of hours or days, terminating in a "crash" with exhaustion and depressive symptoms.
5.19 As the effects are relatively short lived and intense, there is a marked drive to repeatedly obtain the drug and avoid the withdrawal symptoms.
5.20 Cocaine may be used in association with other drugs such as alcohol or heroin. The injecting of heroin together with cocaine ("speedballing" or "snowballing") is a highly dangerous practice that is becoming more prevalent in Scotland.
Physical health problems associated with cocaine use
5.21 There is a wide range of physical and psychiatric problems associated with cocaine abuse, many of which are serious and may even be fatal.
5.22 Cardiovascular: Cocaine abuse can be linked to virtually every type of heart disease. Various cardiac arrhythmias (abnormal heart rhythms) can be induced by cocaine. Sinus tachycardia (increase in heart rate) usually occurs soon after its ingestion. Also associated are sinus bradycardia (reduction in heart rate), ventricular ectopics (irregularities in the heart rate), ventricular tachycardia, fibrillation (irregular, excessive and dysfunctional heart rhythm) and asystole (no heart beat). Blood pressure is affected causing hypertension that is dose related and may result in strokes. Spasm may occur in the coronary arteries resulting in myocardial infarction (heart attack). Long term cocaine abuse may lead to interstitial fibrosis (a lung disorder) and eventually to congestive cardiac failure.
5.23 With chronic use the cardiovascular system is prematurely aged. This and the other cardiovascular effects are of particular relevance to Scotland where the prevalence of cardiovascular problems is particularly high anyway.
5.24 Neurotoxicity: Cocaine may cause seizures or unmask a epilepsy. Cerebrovascular ischaemia (decreased oxygen to the brain) may result in small ischaemic cerebral infarcts (strokes) and haemorrhagic cerebrovascular accidents (bleeding into the brain) may be associated with hypertensive episodes. Brain perfusion deficits and associated neuropsychological compromise (such as deficits in attention, concentration, new learning, visual and verbal memory and word production) may be persistent. Tics, stereotypies of speech or movement, ataxia and disturbed gait may occur which may disappear after the drug use is stopped.
5.25 Sexual function: Chronic use may result in hyperprolactimaemia (altered hormone function) and gynaecomastia (breast growth) together with impotence. There are also incidences of deranged menstrual function, galactorrhea, amenorrhea and infertility.
5.26 Other effects: The drive to eat in chronic cocaine users is depleted resulting in significant weight loss and poor nourishment leaving the individual more susceptible to infection. Hyperpyrexia (uncontrolled raising of the body temperature) may occur due to hypermetabolism associated with peripheral vasoconstriction and impairment in the ability to regulate body heat. Rhabdomyolysis, a muscle wasting condition, has been associated with cocaine abuse. This may lead onto acute renal failure and disseminated intravascular coagulation and possible death.
5.27 Many of the potential health risks of cocaine use are specific to the route by which the drug is taken. Intranasal use can result in sinusitis, loss of sense of smell, nasal mucosa atrophy (destruction of the lining of the nasal passages), nose bleeds, nasal septum perforation, hoarseness and problems with swallowing. Taking cocaine orally can result in bowel ischaemia or necrosis (death of the bowel tissue) and gangrene. This is usually associated with "body-packers" who have swallowed condoms filled with cocaine that subsequently burst.
5.28 Smoking crack can result in 'crack lung' which presents with the symptoms of severe chest pains, breathing problems and high temperature and can proceed onto respiratory failure and death, severe chest pain or dyspnoea. A variety of other respiratory effects of smoking cocaine have been reported including chest pain, breathlessness, pneumonia, pulmonary oedema (fluid in the lungs), pneumothorax (air escaping from lungs into the chest), pneumopericardium (air around the heart), diffuse alveolar haemorrhage (bleeding into the lungs), haemoptysis (coughing up blood) and asthma. Respiratory failure may occur resulting in death. The hot vapour inhaled during smoking may result in burns to the lining of the mouth and throat of which the user may be initially unaware due to the anaesthetic actions of the cocaine.
5.29 Intravenous use can result in cellulites (skin infection), abscesses, septicaemia, endocarditis (chronic infection of the heart lining and valves), arterial thrombosis (blood clots), renal infarction (death of parts of the kidney), and thrombophlebitis. Sharing of injecting equipment raises the risks of contracting a range of infectious diseases including septicaemia, hepatitis B & C, HIV and subsequently AIDS.
5.30 Poisoning with ammonia from protracted use of poorly manufactured crack is a potential health risk as are problems associated with acetone (used to reclaim cocaine from crack pipes) which may cause kidney, liver and nerve damage
5.31 Alcohol is often taken along with cocaine. In the body this forms a third substance, cocaethylene. Cocaethylene has similar effects to cocaine but lasts longer before being broken down by the body. It is also more toxic and causes more physical harm, especially to the cardiovascular system, accentuating the premature aging of this system, development of atherosclerosis and increasing the overall morbidity and mortality associated with cocaine use. This is of particular importance in Scotland, which already has a high incidence of cardiovascular morbidity.
Psychiatric problems associated with cocaine use
5.32 Psychiatric problems due to cocaine use are common with chronic use, high dose or bingeing episodes and appear particularly associated with the use of "crack" cocaine. General symptoms which have been described include impaired judgement, grandiosity, combativeness and extreme psychomotor stimulation. Anxiety and panic attacks during the use of cocaine are common. With chronic use of cocaine such reactions can occur spontaneously without drug-induced stimulation and may persist even after the use of cocaine has stopped. Depressive symptoms often occur especially following a period of heavy use, the "crash" and can be so severe as to lead to suicidal thoughts or acts.
5.33 Chronic use or heavy binges can lead to the development of paranoid ideation associated with anxiety. This may progress onto a psychotic disorder with paranoid delusions of persecution, hallucinations (which may be auditory or tactile "cocaine bugs"), anxiety with panic attacks, psychomotor hyperactivity and agitation. Confusion and aggressive behaviour may develop and in such a state, which some term "excited delirium", violent behaviour may ensue and the individual require restraint and detention prior to treatment. During such restraint, however, sudden deaths have been reported. The symptoms usually resolve over hours or days of stopping the cocaine use but may be more persistent.
5.34 Cocaine use can lead to impairments in brain function through decreased perfusion and multiple small ischaemic infarcts (strokes). This may affect the ability of the individual to take part in treatment successfully.
Effects of maternal stimulant use on the fetus and children
5.35 Recent animal studies suggest that cocaine may be particularly harmful to the fetus in the early stages of brain development. Mainly American research has shown that babies whose mothers used crack/cocaine during pregnancy can suffer a variety of serious consequences. They are more likely than matched controls to be born prematurely, and to be smaller and lighter. Marked withdrawal symptoms can occur soon after birth. A number of controlled studies have shown that children of cocaine using mothers are more likely to develop cognitive, attention disorders and anti-social or offending behaviour.
5.36 There has been little research on maternal amphetamine use. What there is suggests the effects are similar to those of cocaine. The effects on the fetus of exposure to multiple drugs that include stimulants are unpredictable but likely to be harmful.
5.37 The extreme mood swings and erratic behaviour that characterise heavy stimulant use are not conducive to good parenting.
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