Chapter 53. Substance abuse
Alcohol dependence
Of the UK population, 2% suffer from alcohol dependence syndrome at any time.
Dependence is most common in:
• Those aged 40–54 years
• The divorced and separated
• Those who have never been married
• Publicans, doctors, journalists and senior businessmen are most vulnerable.
Factors increasing risk of dependence include:
• Cheap or easily available alcohol
• Unsupervised work routine
• Unsociable working hours
• Work involving separation from family or other stabilising social constraints.
Effects of alcohol
Psychological effects of alcohol
• Hallucinations of voices (alcoholic hallucinosis), which are usually derogatory in content, may occur in clear consciousness
• Depressive symptoms occur in 90% of people with alcoholism and there is a 10–15% risk of completed suicide associated with alcoholism
• Pathological jealousy manifests as a morbid delusional belief that a partner is being unfaithful and may put the partner at risk of serious violence.
• Liver damage
• Alcoholic hepatitis
• Fatty liver
• Cirrhosis
• Liver failure and hepatic encephalopathy
• Oesophagitis and gastritis causing vomiting and retching
• Mallory–Weiss tear in lower oesophagus causing haematemesis
• Portal hypertension causing oesophageal varices and possible massive haematemesis
• Peptic ulceration
• Acute and chronic pancreatitis (acute has a mortality of 10–40%)
• Carcinoma of upper gastrointestinal tract.
• Cardiac arrhythmias
• Cardiomyopathy
• Coronary artery disease
• Hypertension
• Cerebrovascular accident.
Metabolic
• Hypoglycaemia
• Ketoacidosis.
Haematological
• Anaemia
• Thrombocytopenia.
• Diffuse brain damage from cortical shrinkage and ventricular dilation
• Alcoholic dementia
• Wernicke–Korsakoff syndrome
• Seizures from alcohol withdrawal.
Wernicke–Korsakoff syndrome is caused by deficiency of thiamine (vitamin B1).
In acute Wernicke’s encephalopathy, symptoms include alteration in level of consciousness, nystagmus, external ophthalmoplegia, ataxia and peripheral neuropathy.
Alcoholics are frequently prescribed oral thiamine and given IV thiamine preparations in hospital.
Medical emergencies specifically related to alcohol
Acute intoxication
Acute intoxication may lead to physical injury from trauma or head injury and predisposes to hypoglycaemia.
Alcohol alone should never be accepted as a cause of reduced or lost consciousness
Acute alcohol withdrawal
Acute alcohol withdrawal occurs in the dependent state and is characterised by:
• Nausea
• Vomiting
• Tremors
• Excessive sweating
• Tachycardia.
It may begin within 6 hours of cessation or reduction of alcohol and peaks by 48 hours, subsiding over the next 7 days. It can be associated with withdrawal grand mal epileptic seizures 12–24 hours after drinking.
Delirium tremens
Delirium tremens (‘the DTs’) occurs on days 3–5 following cessation or significant reduction of drinking in an alcohol-dependent person. It is characterised by:
• Confusion
• Disorientation
• Delusions
• Hallucinations
• Vivid imagery (often insects but not the pink elephants of popular belief)
• Intense tremulousness.
There is often a marked lability of emotions and autonomic dysfunction. There is no craving for alcohol. Admission to a medical ward for rehydration, sedation and nutrition is essential. In 50% of cases DTs are precipitated by an intercurrent infection. The mortality rate is up to 10%.
Abuse of other substances
• Unusual behaviour of any sort could be due to substance misuse
• Check patient’s arms and legs for evidence of injection sites
• Misusers of volatile solvents often smell of glue or aerosol propellant and may have a rash around their mouth and nose where there has been contact with an inhalation bag
• Street names vary in different geographical areas and also change over time. If in doubt, it is best to ask for, or suggest, the generic name of the substance and seek confirmation from the patient.
Opiates
Overdose or ingestion of opiates is characterised by:
• Altered level of consciousness
• Respiratory depression
• Pinpoint pupils
• Euphoric or stuporous mental state
• Convulsions (rare)
• Hypotension (rare)
• Hypothermia. (rare)
The initial management of an opiate overdose or respiratory depression due to opiate ingestion is:
• Maintenance of the airway and oxygenation followed by
• Administration of naloxone.
Naloxone will wear off faster than the opiate
Hallucinogens
Lysergic acid diethylamide (LSD)
• LSD is a synthetic psychedelic drug of low toxicity. Symptoms include confusion, agitation, hallucinations, dilated pupils, and (rarely) coma and respiratory arrest. Supportive measures only are required.
Psilocybin (magic mushrooms)
• Ingestion of magic mushrooms is a seasonal problem, usually well known in particular localities where the mushrooms can be picked. Cases may occur in small epidemics. The fatal dose is unknown
• Euphoria, anxiety, depression, illusions and psychosis are all common manifestations. Hyperthermia, tachycardia, tremors and dilated pupils are characteristic. There is no specific treatment in the prehospital setting but efforts should be made to calm the victim by giving reassurance that the effects are self-limiting.
Phencyclidine
• Phencyclidine is a psychedelic drug, fatal dose unknown. Symptoms include anxiety and psychosis, ataxia, paraesthesia, catatonic movements, fits, coma, hypotension, respiratory impairment, Cheyne–Stokes breathing and respiratory arrest. Treatment is supportive.
Cannabis
• There is evidence to support the use of cannabis and the development of mental problems, including psychosis
• Of relatively low toxicity (unless ingested by children when coma may ensue), it may be smoked or eaten
• The symptoms of toxicity include excitement, euphoria, drowsiness, panic attacks, toxic psychosis and, rarely, coma and dilated pupils. No specific treatment is required in the prehospital setting apart from supportive measures.
Amyl nitrate
• Amyl nitrate is toxic by ingestion and inhalation. Its principal mode of toxicity is by the formation of methaemoglobin. The fatal dose is unknown, but even small amounts can cause symptoms
• Symptoms occur within a few seconds of inhalation, but may be delayed by ingestion. Headache, nausea and vomiting occur along with sweating and flushing. Tightness of the chest is common, as is confusion and occasionally fits
• Cyanosis due to methaemoglobinaemia may occur. There is no specific prehospital treatment apart from maintenance of the airway and administration of oxygen to treat cyanosis.
Remember that the presence of methaemoglobinaemia will make pulse oximetry unreliable
Stimulants
Amphetamines
• Dexamphetamine (Dexedrine, ‘dexies’) and amphetamine-like drugs such as methylphenidate (Ritalin) and diethylpropion (Tenuate) may be abused
• The acute effects of amphetamines include euphoria, anxiety, increased energy, miosis and tachycardia
• Amphetamine psychosis mimics acute symptoms of schizophrenia and manifests with paranoid delusions, auditory, visual and tactile hallucinations and increased arousal and irritability. Consciousness is impaired
• Withdrawal effects include dysphoria, fatigue, lassitude and depression.
Cocaine
• The fatal dose is approximately 1 g when taken orally and 10 mg when injected
• Symptoms include tachycardia, sweating, hallucinations, increased respiratory rate, increased temperature, fits, arrhythmias and rarely cardiac arrest
• There is no specific treatment; fits should be controlled with diazepam and general supportive measures instituted
• Crack is a processed form of cocaine which produces a much quicker ‘high’ which is of short duration. It is much more addictive than cocaine.
Ecstasy (MDMA)
• A semisynthetic amphetamine (3,4-methylenedioxymethamphetamine)
• Two causes of death are commonly recognised: early deaths are due to arrhythmias and late deaths are due to an effect on muscles associated with a fatal rise in body temperature
• Deaths can occur after exposure to doses previously tolerated and are thought to be due to an idiosyncratic reaction
• Symptoms range from mild to life-threatening and include muscle spasms, dilated pupils, anxiety, tachycardia, increased temperature, abdominal pain, hypotension, fits, coma and stroke
• The fatal dose is unknown
• There are no specific treatments other than supportive measures in the prehospital setting
• Gamma-hydroxybutyrate (GHB) or ‘liquid ecstasy’ has similar effects and is dangerous when mixed with alcohol or other recreational drugs.
Ephedrine
• Ephedrine is a sympathomimetic drug with a fatal dose of 200 mg in children and over 2 g in adults. It causes restlessness, tachycardia, dilated pupils, arrhythmias and hallucinations
• Apart from treating fits with diazepam, there is no specific prehospital treatment but supportive measures should be instituted.
Sedatives
Barbiturates
• The barbiturates are a group of drugs that include amylobarbitone (Amytal), barbitone, pentobarbitone (Nembutal), phenobarbitone and sodium amylobarbitone (sodium Amytal)
• Symptoms of overdose include ataxia, dysarthria, decreased conscious level, coma, respiratory depression, hypothermia and hypotension
• There are no specific treatments apart from general supportive measures. Withdrawal seizures may occur and should be controlled with diazepam.
Volatile solvents
Glue
• Toluene is the most common solvent in glues available over the counter. Effects include excitement, chest tightness, fits, coma, arrhythmias and death
• Supportive measures should be instituted with particular emphasis on oxygenation to reduce the likelihood of arrhythmias.
Butane
• Butane is a colourless, odourless gas, commonly used as the propellant in ‘ozone-friendly’ sprays but also available in cigarette lighters. It is generally inhaled from a bag. Symptoms include respiratory depression, coma, hypotension and arrhythmias. Treatment is supportive only.
Butyl nitrate
• An industrial solvent, butyl nitrate is also used as a room deodoriser. It can be fatal when ingested in even small quantities, but the fatal dose is unknown. Symptoms include flushing, tachycardia, hypotension, confusion, shortness of breath and cyanosis (from the formation of methaemoglobin), coma and fits. Treatment is supportive. Remember that pulse oximetry readings are likely to be inaccurate.
For further information, see Ch. 54 in Emergency Care: A Textbook for Paramedics.
