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Clinical Features

The pattern of presenting problems depends on a variety of factors including:

Substance abuse can have a number of detrimental effects as follows:

Amphetamines Cannabis Heroin and other opioids Nitrites (Poppers)
Anabolic steroids Cocaine Ketamine Phencyclidine (angel dust)
Barbiturates Ecstasy Khat Psilocybe mushrooms
Benzodiazepines Gamma hydroxybutyric acid (GHB) LSD (lysergic acid diethylamide) Solvents (volatile substances)

Amphetamines

The amphetamines constitute a large group of chemicals related to adrenaline. The term amphetamine refers to amphetamine and methamphetamine (crystal meth) which is more widely used in the USA. Amphetamine is a stimulant which increases wakefulness and suppresses appetite. However it impairs judgement and reduces learning ability. Amphetamine and related drugs have also been used as appetite suppressants. They also improve athletic performance and have been banned in sport.

Amphetamine is abused because it causes a “buzz” with increased alertness and energy. This consists of over talkativeness, over-activity, insomnia, dryness of the lips, mouth and nose, anorexia, dilated pupils, fast pulse and high blood pressure, irritability, confusion, anxiety and panic. Larger doses can lead to cardiac arrhythmia, very high blood pressure, stroke and rarely circulatory collapse. Even higher doses can lead to fits and coma. After using it the user tends to fall into an exhausted sleep and wake extremely hungry.

Long term adverse effects include:

Addiction is not common but does occur. In persistent users, withdrawal results in depression, anxiety, fatigue, lethargy and nightmares. Intense craving and suicidal thoughts are sometimes seen.

Anabolic steroids

Anabolic steroids are synthetic drugs related to natural hormones such as testosterone. Their main property is to promote protein building by the body and they are used to enhance athletic performance. They have been banned in sport. Heavy use can lead to aggressive behaviour with violent outbursts and depression. Unwanted physical effects include testicular atrophy, acne, breast development in men and premature arterial disease.

Barbiturates

Barbiturates were widely used as sedative drugs but were replaced by benzodiazepines in the 1970s. Phenobarbitone, one of the barbiturates, is still used to control epilepsy. The abuse of these drugs and their wide use for suicidal overdose led to a marked reduction in their prescribing in the 1970s. Surveys of drug use do not usually ask about barbiturates nowadays because their use has become rare.

They produce an alcohol like state of intoxication. Long term adverse effects include depression, mood swings, fatigue, impairment of memory and judgment and poor coordination. They are addictive and withdrawal can produce severe reactions that include epileptic fits.

Benzodiazepines

Benzodiazepines are a group of tranquillising drugs that include diazepam (Valium), nitrazepam (Mogadon), temazepam and lorazepam. The benzodiazepines were widely prescribed for their hypnotic and anxiolytic effects, until the 1980s when it became apparent that many people had become dependent upon them. They are now only recommended for short term use (up to two weeks) for the relief of anxiety or insomnia or occasionally as muscle relaxants, to treat the symptoms of alcohol withdrawal or to treat epilepsy.

Temazepam was regularly abused in the 1980s by injecting the gel of temazepam capsules. The scale of the problem was reduced by withdrawing temazepam capsules and only allowing prescription of tablets in the UK. However, the potential for abuse by injection remains for those drugs that are easily soluble, for example, diazepam.

Benzodiazepine dependence in the UK is usually secondary to long term prescribing in people with anxiety disorders and insomnia. However, benzodiazepines may be abused by people who abuse other drugs or alcohol. Abuse may be binge like and non dependent, for example benzodiazepines are used to boost the euphoria of heroin, cushion the “come down” from cocaine or alleviate withdrawal symptoms when drugs such as heroin are unavailable. Abuse may be dependent, and these people may experience tolerance to the sedative effects of the drug without tolerance to the other effects. This may lead to the person taking very large doses resulting in amnesia and risk taking behaviour without appearing to be sedated.

Intoxication with benzodiazepines can cause slurred speech, inco-ordination, unsteady gait, impairment in attention or memory and behavioural dis-inhibition, which might cause hostile or aggressive behaviour.

Withdrawal symptoms include anxiety, irritability, sweating, tremor, sleep disturbance, altered perception, depersonalisation, derealisation, hypersensitivity, abnormal sensations, depression, psychosis, seizures and delirium tremens (DTs). Some withdrawal symptoms can be very prolonged like difficulty sleeping, anxiety and irritability causing great difficulty coming off benzodiazepines.

Cannabis

Cannabis (marijuana) is a product of the cannabis (Indian hemp) plant. It is used in three forms: the leaves (grass, pot); resin (hash) and liquid (cannabis oil). Tetrahydrocannabinol (THC) is the main active substance. Normal cannabis contains about 5% THC, but “skunk”, a cannabis plant that is grown under forced conditions contains 10 to 30%. Cannabis can be smoked, eaten or injected.

Cannabis produces a pleasurable feeling of intense relaxation and detachment. Some people feel dysphoric (a state of unpleasant mood, the opposite of euphoria), depressed, paranoid, have acute transient psychotic episodes or have panic attacks when they use it. It slows reactions and impairs concentration and memory up to 24 hours after use, affecting the ability to drive and operate machinery. It raises the heart rate and blood pressure.

Long term adverse effects include:

It has been suggested that prolonged heavy use can result in an “amotivational syndrome” consisting of apathy, withdrawal, lethargy and lack of motivation, but this has not been proven. “Flashbacks” i.e. experiencing symptoms of cannabis intoxication days or weeks after last using cannabis have been described in cannabis users but the significance of these is unclear.

It is not clear whether cannabis can cause schizophrenia but it can exacerbate the symptoms of schizophrenia in a person with the condition and can increase the risk of relapse in people with schizophrenia.

There is now more evidence of the association between cannabis use and onset of psychotic disorders. Cannabis use confers an overall twofold increase in the relative risk for schizophrenia. It seems that cannabis use accelerates the onset of psychosis in vulnerable individuals. Schizophrenia is identified at a younger age in people with a previous diagnosis of cannabis induced psychotic disorders.

There is evidence that chronic use in adolescence may impair school performance and educational achievement.

Cannabis has similar carcinogens to tobacco smoke but in higher concentrations and may increase the risk of cancers of the head and neck. It reduces sperm production and fertility in men. Long-term use could result in chronic obstructive pulmonary disease.

Dependence is common among daily users, but withdrawal symptoms are usually mild. These include irritability, nausea, insomnia and anorexia.

Cocaine

Cocaine is derived from the coca plant which is widely grown in Latin America. It is usually inhaled (snorted) or injected.

More recently, a free base form of cocaine called “crack” has been introduced into the UK. There is some evidence to suggest that “crack” is more addictive than normal cocaine. It reaches the brain faster than injected cocaine and produces an immediate “high”. It is extremely addictive and may lead to compulsive cocaine abuse to the exclusion of all other activities.

When cocaine is taken there is a brief intense “high” which tends to be followed by a “come down” or crash. Many users try to extend the “high” by using repeated doses but they eventually come down feeling exhausted, anxious and hungry. Cocaine use leads to excitement, increased energy, euphoria, grandiose thinking, impaired judgement and sexual dis-inhibition. Higher doses can cause hallucinations, paranoid ideation and aggressive behaviour. Physical effects include dilatation of pupils, fast pulse and raised blood pressure.

Long term adverse effects include:

Cocaine is addictive and the craving can last for several months after the last dose. Withdrawal symptoms include dysphoria (emotional state characterised by anxiety, depression or unease), anhedonia (the absence of pleasure or the ability to experience it), fatigue and hypersomnolence. Severe withdrawal is seen in prolonged use of high doses and crack cocaine and symptoms include intense craving, depression and suicidal thoughts.

Ecstasy

Ecstasy is the chemical name for 3, 4 methylenedioxymethamphetamine (MDMA), which is related to, and has similar effects to amphetamine. However it also causes a feeling of well being and closeness to others, which together with the amphetamine like surge in energy make it a popular drug at parties, clubs and raves. It is usually taken as tablets (occasionally capsules or powder form, intranasally, rectally or rarely intravenously) and users often increase the dose from one or two to several over a period of a few months.

The drug starts to take effect after 30 to 60 minutes and peak effects are reached between 90 and 120 minutes after ingestion, persisting for a further 3 to 6 hours followed by a gradual “come down” over the subsequent 6 to 12 hours.

Under the stimulant effect of the drug, people may continue to dance for several hours without drinking and deaths have been reported as a result of dehydration and hyperthermia. Conversely, some people become ill as a result of fluid overload because they have drunk excess fluids without dancing. Other physical effects include loss of appetite, fast pulse, sweating and compulsive grinding of teeth.

Adverse reactions can be psychological or physical. Psychological reactions include increased anxiety, panic and agoraphobia; major depressive disorder; prolonged depersonalisation; prolonged psychoses and flashbacks. Serious physical complications include hyperthermia and dehydration, stroke, cardiac arrhythmias and liver failure.

Unlike other drugs, the sporadic use of MDMA for recreational ends may generate significant neuropsychological deficits. These deficits are mainly involving brain regions involved in memory and working memory functions.

Long-term adverse effects therefore include impairment of memory and learning and possibly depressive illness later in life with prolonged use. This is because MDMA is toxic to nerve endings (serotonin terminals) in the brain.

Although dependence will occur if ecstasy is taken on a daily basis there have been no reports of people using the drug frequently enough for this to occur. In fact, ecstasy is unusual in that the effects of the drug tend to decrease the more often it is taken and this does not disappear even after a period of abstinence.

Gamma hydroxybutyric acid (GHB)

GHB is a central nervous system depressant with effects similar to alcohol. Body builders have used it to increase muscle bulk and more recently it has become an abused substance. It is available as a colourless liquid, powder or capsules. Users drink small quantities until they experience a euphoric “high”.

The effects begin up to 40 minutes after ingestion and lasts between 8 and 24 hours. Low doses produce euphoria and dis-inhibition; higher doses produce sedation and possibly nausea and vomiting. Acute physical complications include respiratory depression, seizures, and coma (usually with full recovery).

A withdrawal syndrome has been described characterised by insomnia, tremor and anxiety.

Heroin and other opioids

Opioids are substances that have morphine like effect on the body. Natural opioids (alkaloids) contained in the resin of the opium poppy include morphine and codeine. Semi synthetic opioids include heroin and synthetic opioids include methadone. The main medicinal use of opioids is as an analgaesic.

The acute psychological effects of opiates vary depending upon dose and route but include sedation, euphoria, emotional numbing and induction of a dream like state. It can be injected, snorted as a powder or inhaled as a vapour (chasing the dragon).

Overdose of an opiate produces drowsiness, respiratory depression and coma and this can be fatal. One of the major reasons for accidental overdose of heroin is that tolerance decreases rapidly after 2 to 3 weeks of abstinence, so that previous normal doses are too high to be tolerated.

Long term adverse effects include:

Heroin is highly addictive and repeated use for 2 to 3 weeks leads to tolerance, which results in the need to increase the dose to achieve the same effect (often tenfold or more). It needs to be taken four or five times a day to prevent withdrawal. Sudden withdrawal results in intense craving, restlessness, insomnia, muscular pains, runny nose and eyes, sweating, abdominal cramps, diarrhoea, goose flesh (cold turkey), vomiting, dilated pupils, fast pulse rate and disturbance of temperature. The withdrawal illness can last for up to 10 days but is immediately relieved by taking more of the drug. The withdrawal syndrome is not usually considered to be life threatening.

Buprenorphine (Temgesic, Subtex) is an opioid analgaesic that is taken sublingually (under the tongue). It does have the potential for abuse and may be injected although it is less likely than heroin to cause respiratory depression in overdose. It can be used in the treatment of heroin addiction.

Methadone is also addictive, but is used for maintenance treatment of heroin addicts because it only needs to be taken once daily by mouth. It therefore reduces crime associated with heroin abuse and reduces injecting, helping to reduce the spread of HIV and Hepatitis B and C. It may cause drowsiness and overdose can be fatal. Methadone itself can be abused and use of methadone does not prevent the person from taking other substances or injecting heroin as well.

Ketamine

Ketamine is an anaesthetic/analgaesic related to phencyclidine and has become associated with the “rave” music scene. It is available as a powder or capsules (for example, Special K) and may be ingested or snorted.

After oral ingestion, effects appear after 20 minutes and last up to 3 hours. When snorted the onset of action is more rapid and the duration of effects is shorter. Acute effects include a general stimulant effect (being put into overdrive), euphoria, depersonalisation, out of body floating experiences, perceptual distortion and hallucinations.

Acute adverse effects include emergence phenomena, like waking from anaesthesia such as vivid dreams, hallucinations and delirium; fast pulse, arrhythmias, and hypertension; nausea and vomiting; nystagmus (rapid jerking eye movements); numbness (with a risk of accidental burning or other traumatic injury); ataxia (unsteadiness) and slurred speech; raised intra-cranial and intra-ocular pressure. High doses could result in respiratory failure.

Long term adverse effects include flashbacks; panic attacks, depression, psychosis and chronic memory impairment. Tolerance to ketamine may occur and a small minority become psychologically dependent on the drug experience. There is no physical withdrawal syndrome.

Khat

Khat is a stimulant obtained from an evergreen shrub that grows in parts of East Africa and the Middle East. The main psychoactive substances in khat are cathine and cathinone, which are related to amphetamine. In many countries it is used as in social settings such as informal groups, weddings and other celebrations. It is not an illegal substance in the UK, where it is mainly abused by Middle Eastern and West African expatriates. It is chewed, usually for about two hours, and the juice is swallowed. Effects start within 15 minutes of chewing and usually consist of talkativeness and mild euphoria. However, aggressive verbal outbursts or hallucinations may occur, as may nausea, vomiting, abdominal pain, headache and palpitations.

Long term adverse effects include loss of appetite, migraine, psychotic behaviour, constipation and stomach ulcers.

Khat use has the potential to develop into dependency. However it seems this is much less likely than dependency on stimulants such as amphetamine and more like the type of dependency seen with caffeine. The vast majority of people who chew khat do not use it in a dependent fashion and there is no evidence of more widespread drug abuse amongst khat users.

LSD (lysergic acid diethylamide)

LSD is a hallucinogen. The usual dose is small (50 to 150 micrograms) and is usually taken by mouth on small paper squares. The effects usually start within 30 minutes and last up to 12 hours depending on the dose. It produces distortions in shapes and colours and the passage of time appears to be slowed. Body image may be distorted with a feeling of being outside one’s body. The effects are usually pleasant but may be menacing and unpleasant resulting in a panic reaction (“bad trip”). The user may occasionally be threatening or violent, usually because of paranoid delusions about their surroundings.

Long term adverse effects include hallucinogen persisting perception disorder (flashbacks) and prolonged psychoses. Flashbacks are recurrent visual disturbances that occur in a minority of users. They may resolve over a period of months or years after last drug use but persist in about 50%. Hallucinogen persisting perception disorder is associated with a high risk of panic disorder, major depression and alcohol dependence. Prolonged psychotic episodes may occur, which resemble good prognosis schizophrenia. Symptoms include change in affect or mood, visual hallucinations, auditory hallucinations, delusions and mystical preoccupations. People with prolonged psychotic episodes tend to have less thought disorder, and fewer negative symptoms than people with schizophrenia. Insight tends to be retained. There is a high risk of suicide.

Dependence does not occur.

Nitrites (Poppers)

Poppers are the street term for nitrites taken for recreational purposes through direct inhalation. They usually contain amyl nitrite, butyl or isobutyl nitrite and are obtained as a yellow liquid in brown bottles with names such as “gold” and “rush”. Their use is not illegal in the UK. Nitrites relax smooth muscle. They are used in clubs and at parties and are used by the homosexual community because they relax the muscles of the anus. The vapour from the liquid is either sniffed directly or by soaking on a cloth. The effects are immediate and last only a few minutes. These include a euphoric rushing sensation, skin flushing, a fall in blood pressure and increase in heart rate. Fainting, loss of balance, headache and nausea can occur. Dermatitis of the skin of the nose and mouth can occur. Swallowing poppers can result in difficulty in breathing, convulsions, loss of consciousness and deaths have been reported.

Tolerance can develop after 2 to 3 weeks continuous use, but this disappears if the user stops for a few days and they do not appear to be addictive.

Phencyclidine (angel dust)

Phencyclidine was developed as a dissociative anaesthetic agent but its use was abandoned due to adverse reactions like delirium and hallucinations. Use is not common in the UK.

Acute intoxication causes phencyclidine delirium. The severity of this varies according to the dose of the drug. Lower doses cause hallucinations, confusion and ataxia (unsteadiness) and higher doses may lead to stupor and coma. Aggressive behaviour can result in suicide and homicide. Analgaesia of fingers and toes may occur.

Other adverse effects include hypertension, hyperthermia, opisthotonus (severe hyperextension and spasticity in which the head, neck and spinal column enter into a complete "bridging" or "arching" position), cardiac arrhythmias, seizures, stroke, muscle spasm and renal failure (in 2.5% of users). Delirium may be followed by a chronic psychosis that is similar to schizophrenia. Tolerance and dependence can occur but withdrawal symptoms are very rare.

Psilocybe mushrooms

Commonly known as “magic mushrooms” or “liberty caps”, these are widely used among young people. Use is usually either experimental or a “lifestyle feature”. They are small brown mushrooms which contain two substances, psilobycin and psilocin. They may be eaten raw or cooked and can be made into tablets. It usually takes 30 to 50 mushrooms to produce a hallucinogenic experience similar to that experienced with LSD. This occurs between 30 minutes and four hours after ingestion and can last for up to 12 hours. Adverse physical effects include nausea and vomiting, abdominal pain, dizziness and increase in pulse rate and blood pressure. The main physical danger occurs if other similar looking poisonous mushrooms are taken by mistake. Ingestion of some of these can be fatal. Adverse psychological effects include a “bad trip” where anxiety results from the hallucinations. Acute confusional states and acute psychotic reactions can occur but these normally resolve within 24 hours.

Magic mushrooms are not addictive.

Solvents (volatile substances)

Solvents are commonly abused by school age children (glue sniffing). Substances containing solvents that are abused include glues, dry cleaning fluids, petrol, paint strippers or thinners, butane gas cigarette lighter refills and aerosols such as deodorants or hair sprays.

Clinical effects are similar to alcohol intoxication. The nervous system is first stimulated and then depressed. The stages of intoxication are euphoria, blurred vision, slurred speech, inco-ordination, staggering gait, nausea, vomiting and coma. It may induce delusions and there may be frightening visual hallucinations.

Sudden death may occur. The main causes are cardiac arrhythmias and respiratory depression. Other causes of sudden death include trauma, asphyxiation when using plastic bags over the head and inhalation of stomach contents.

Long term adverse effects in chronic users include -:

Dependence can occur but physical withdrawal symptoms are very rare. Withdrawal symptoms include irritability, nausea, sleep disturbance, increased heart rate and rarely hallucinations and delusions.

Amended June 2008

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