- Email: [email protected]
Substance Abuse
TYPES OF POISONING
Substance Abuse Allister Vale
Many substances, some obtained from natural sources, are taken to alter the mental state of the user. These include amfetamines, cannabis, cocaine, Ecstasy, ethanol, lysergic acid diethylamide, mushrooms, opioid analgesics and volatile substances. Such substances can be classified according to whether their major effect is to alter perception, or to stimulate or depress the CNS, though there is some overlap between groups. Substances that predominantly depress the CNS (e.g. ethanol) may, for example, arouse and disinhibit behaviour before exerting their principal action. Other drugs that initially stimulate the brain may impair consciousness if taken in sufficient quantities.
1 Erythematous skin lesions over the lower abdomen and iliac crests, resulting from ‘skin-popping’.
Routes of abuse Substances may be ingested, inhaled, absorbed through mucous membranes or injected. Ingestion Ingestion is convenient, but absorption is relatively slow and the impact of the drug on the brain is correspondingly decreased, unless large quantities are taken. Drugs taken by ingestion to alter the mental state include anticholinergic drugs and plant preparations, benzodiazepines, clomethiazole, ethanol, opioid analgesics (particularly codeine and dihydrocodeine) and sympathomimetics.
2 The left inguinal region of a man showing a localized depression resulting from repeated use of the femoral vein for intravenous injection.
Inhalation Inhalation allows more rapid absorption of cannabis, cocaine, nicotine, opiate analgesics, organic nitrites (e.g. isobutyl nitrite) and volatile substances. Volatile substances are usually ‘bagged’ (sprayed into a plastic bag and inhaled until the individual loses consciousness) or ‘huffed’ (sprayed onto a cloth held to the mouth). An abuser may attempt to enhance the intoxicant effects by placing a plastic bag over the head.
Absorption through mucous membranes Absorption through mucous membranes (‘snorting’ or ‘snuffing’) is the method most commonly used with cocaine. The drug is sniffed into the nostrils, where it is absorbed. Injection Injection subcutaneously (‘skin-popping’, Figure 1) or intravenously (‘mainlining’, Figure 2) is the fastest method of delivering drugs to the brain in high concentrations. Intravenous injection is the route preferred by most abusers for the more potent opioid analgesics.
Hazards of abuse Accidental overdose is possible, though the degree of risk depends, to some extent, on the route of administration. Intravenous injection carries the greatest risk, because some users are inexperienced at injection technique and because there may be unexpected increases in the potency of street drugs. Because substance abuse is usually illegal, even unconscious or seriously ill individuals may not be referred immediately for medical help, and may be simply
Allister Vale is Director of the National Poisons Information Service (Birmingham Centre) and the West Midlands Poisons Unit at City Hospital, Birmingham, UK. He is a past President of the European Association of Poisons Centres and Clinical Toxicologists, past Trustee of the American Academy of Clinical Toxicology and President-elect of the British Toxicology Society.
MEDICINE
23
© 2003 The Medicine Publishing Company Ltd
TYPES OF POISONING
• bacterial infection of veins and heart valves • candidiasis • inadvertent intra-arterial injection, leading to digital gangrene (Figures 3 and 4).
Body-packing ‘Body-packing’ is the practice of smuggling drugs in small packets (condoms, foil and cellophane are commonly used) that are swallowed for later retrieval from vomit or faeces, or are inserted into the vagina or rectum. A surprisingly large number of packets can be concealed in this manner. Acute intestinal obstruction may result, and overdose is a hazard if a packet bursts. 3 A gangrenous forefoot resulting from intra-arterial injection of drugs.
Management • All patients suspected of body-packing should undergo abdominal radiography on presentation. CT of the abdomen should be arranged as soon as possible. • A urine screen for drugs of abuse should be performed on admission. A screen that is positive for one or more drugs suggests that either the patient has abused the drug in the previous few days, or at least one packet is leaking. A negative screen strongly suggests that no packet is leaking. Screens should be repeated daily, or immediately if the patient develops features of intoxication, to confirm the diagnosis. • Packets that remain in the stomach have been retrieved by endoscopy and by inducing emesis, but these are potentially dangerous procedures and are best avoided. • Optimal management of patients with packets in the small bowel is uncertain. If there is no clinical, analytical or radiological evidence to support leakage, the use of sorbitol or lactulose, with or without bowel stimulants (e.g. bisacodyl) to encourage transit through the gut, is successful in many cases. Alternatively, for faster results, whole-bowel irrigation using polyethylene glycol electrolyte solutions can be used. Liquid paraffin should not be used because it can weaken rubber, leading to bursting of the packets. Activated charcoal has been advocated by some, but induces constipation when used in substantial doses to surround a large number of packages, and is therefore contraindicated. • Packets in the colon or rectum are probably best managed by giving sorbitol or lactulose and allowing them to pass spontaneously, with least risk of rupture. • Immediate surgery is indicated if acute intestinal obstruction develops, or when packets can be seen radiologically and there is radiological, clinical or analytical evidence to suggest leakage, particularly if the drug involved is a CNS stimulant (e.g. cocaine). In this situation, the clinical consequences of poisoning are more serious and management is more difficult than for opioids (Brady et al. 1994) or cannabis. • Packets in the vagina can usually be removed manually and with ease.
observed by their fellow substance abusers until they improve or deteriorate so far that their condition can no longer be ignored. Irreversible brain damage may result. Contaminants Some complications of abuse result from deliberate addition of substances (e.g. quinine, talc) to dilute (‘cut’) the drug before it is sold. In other cases, preparations of the drug for injection (e.g. passage through cigarette filters or cotton wool) introduces contaminants. Particulate contaminants cause long-term, progressive granulomatous pulmonary lesions. Other contaminants, particularly quinine, may be responsible for some of the more acute toxic phenomena seen, and possibly even death. Other hazards Other hazards of drug abuse include: • infection with hepatitis B, C and D virus and HIV • injection site abscess caused by infection or leakage of drug into the tissues
Volatile substance abuse
4 Ischaemic hand and fingers resulting from intra-arterial injection of an opioid. The tourniquet had been placed round the palm of the hand, excluding the thumb. The injection was made into one of the digital arteries, under such pressure that the injected material was flushed back into the palmar arch, from where it was distributed to all the digits.
MEDICINE
Volatile substance abuse is the preferred term for the intentional inhalation of volatile substances (other than conventional anaesthetic agents). It replaces older terms such as ‘solvent abuse’ and ‘glue-sniffing’.
24
© 2003 The Medicine Publishing Company Ltd
TYPES OF POISONING
Commonly inhaled substances include: • toluene-containing glue • chlorinated hydrocarbons (cleaning fluid, paint, varnish, lacquer, dye) • fluorocarbons (aerosol propellant, fire extinguishers) • petrol (gasoline) • acetone (nail polish remover, polystyrene cement) • butane • propane • amyl, butyl and isobutyl nitrites (which may also be ingested). Volatile substances are usually bagged or huffed. Occasionally, aerosols are sprayed directly into the mouth (a particularly dangerous practice), or petrol is drunk mixed with cola or lemonade.
Management: treatment of acute volatile substance poisoning is supportive. It is occasionally necessary to sedate the abuser, to prevent personal harm and injury to others. Diazepam, 10 mg i.v., may be used. Methaemoglobinaemia (if concentration > 30%) should be corrected by intravenous administration of methylene blue, 1–2 mg/kg. Management of chronic volatile substance abuse is psychological rather than physical, in the hope that complications will reverse once abuse ceases.
Clinical features Acute intoxication – the clinical features of volatile substance abuse are similar to those of ethanol intoxication (initial CNS stimulation followed by depression). Features include euphoria, impaired judgement, feelings of omnipotence, blurring of vision, tinnitus, slurring of speech, ataxia and headache. Occasionally, a delirious state is seen, with clouding of consciousness and hallucinations. Convulsions, status epilepticus, respiratory depression and coma may ensue if inhalation of the volatile substance continues. Arrhythmias (e.g. asystole, severe bradycardia, ventricular fibrillation), which are thought to result from sensitization of the myocardium to endogenous catecholamines, are a significant cause of death. Inhalation of volatile nitrites may cause the additional problem of severe or even fatal methaemoglobinaemia. Chronic abuse – the hair, breath and clothing of chronic abusers may smell of solvent, and clothing is often stained by repeated bagging. Bagging may cause erythematous spots around the mouth and nose (‘glue-sniffer’s rash’). Abdominal pain, nausea, vomiting and haematemesis may be the presenting symptoms. Hepatic necrosis (alone or with renal failure) has been reported. School or work performance may be impaired as a result of apathy and poor concentration, and frank dementia has been observed in more severe cases. Toluene abuse characteristically causes cerebellar damage leading to ataxia, tremor, nystagmus and titubation. Pyramidal signs and cranial nerve damage (particularly hyposmia and optic atrophy) have also been reported, and cerebellar and cortical atrophy have been demonstrated by CT. Cerebellar signs may be partly or wholly reversible, however, with cessation of substance abuse. Muscular weakness may be profound, can present as quadriparesis and may mimic Guillain–Barré syndrome; severe hypokalaemia is common in such patients. Toluene and petrol (because of the presence of tetraethyl lead) may cause peripheral neuropathy. Haematuria, pyuria and tubular proteinuria are common in chronic toluene abusers. Renal failure may ensue. Renal tubular acidosis is well recognized, possibly resulting from the permeability of the distal tubule to hydrogen ions, leading to reduced ability to acidify urine. The hypochloraemic acidosis thus induced may be asymptomatic, or may present with severe muscular weakness caused by hypokalaemia or with urolithiasis secondary to hypercalciuria. High anion gap acidosis has also been reported. Dilated cardiomyopathy has been described rarely.
MEDICINE
REFERENCE Brady W J Jr, Stremski E, Eljaiek L et al. Freon Inhalational Abuse Presenting with Ventricular Fibrillation. Am J Emerg Med 1994; 12: 533–6. FURTHER READING Albertson T E, Walby W F, Derlet R W. Stimulant-induced Pulmonary Toxicity. Chest 1995; 108: 1140–9. Aldrighetti L, Pagnelli M, Giacomelli M et al. Conservative Management of Cocaine Packet Ingestion: Experience in Milan, the Main Italian Smuggling Center of South American Cocaine. Panminerva Med 1996; 38: 111–16. Brady W J Jr, Stremski E, Eljaiek L et al. Freon Inhalational Abuse Presenting with Ventricular Fibrillation. Am J Emerg Med 1994; 12: 533–6. Cox M J, Hwang J C F, Himel H N et al. Severe Burn Injury from Recreational Gasoline Use. Am J Emerg Med 1996;14: 39–43. Marelich G P. Volatile Substance Abuse. Clin Rev Allergy Immunol 1997; 15: 271–89. Martinez J S, Sala J J G, Vea A M et al. Renal Tubular Acidosis with an Elevated Anion Gap in a ‘Glue Sniffer’. Hum Toxicol 1989; 8: 139–40. O’Donnell A E, Selig J, Aravamuthan M et al. Pulmonary Complications Associated with Illicit Drug Use. Chest 1995; 108: 460–3. Shannon M. Clinical Toxicity of Cocaine Adulterants. Ann Emerg Med 1988; 17: 1243–7. Sporer K A, Firestone J. Clinical Course of Crack Cocaine Body Stuffers. Ann Emerg Med 1997; 29: 596–601. Steffee C H, Davis G J, Nicol K K. A Whiff of Death: Fatal Volatile Solvent Inhalation Abuse. South Med J 1996; 89: 879–84. Tenenbein M. Leaded Gasoline Abuse: The Role of Tetraethyl Lead. Hum Exp Toxicol 1997; 16: 217–22. Young S J, Longstaffe S, Tenenbein M. Inhalant Abuse and the Abuse of Other Drugs. Am J Drug Alcohol Abuse 1999; 25: 371–5.
25
© 2003 The Medicine Publishing Company Ltd
Substance Abuse Allister Vale
Many substances, some obtained from natural sources, are taken to alter the mental state of the user. These include amfetamines, cannabis, cocaine, Ecstasy, ethanol, lysergic acid diethylamide, mushrooms, opioid analgesics and volatile substances. Such substances can be classified according to whether their major effect is to alter perception, or to stimulate or depress the CNS, though there is some overlap between groups. Substances that predominantly depress the CNS (e.g. ethanol) may, for example, arouse and disinhibit behaviour before exerting their principal action. Other drugs that initially stimulate the brain may impair consciousness if taken in sufficient quantities.
1 Erythematous skin lesions over the lower abdomen and iliac crests, resulting from ‘skin-popping’.
Routes of abuse Substances may be ingested, inhaled, absorbed through mucous membranes or injected. Ingestion Ingestion is convenient, but absorption is relatively slow and the impact of the drug on the brain is correspondingly decreased, unless large quantities are taken. Drugs taken by ingestion to alter the mental state include anticholinergic drugs and plant preparations, benzodiazepines, clomethiazole, ethanol, opioid analgesics (particularly codeine and dihydrocodeine) and sympathomimetics.
2 The left inguinal region of a man showing a localized depression resulting from repeated use of the femoral vein for intravenous injection.
Inhalation Inhalation allows more rapid absorption of cannabis, cocaine, nicotine, opiate analgesics, organic nitrites (e.g. isobutyl nitrite) and volatile substances. Volatile substances are usually ‘bagged’ (sprayed into a plastic bag and inhaled until the individual loses consciousness) or ‘huffed’ (sprayed onto a cloth held to the mouth). An abuser may attempt to enhance the intoxicant effects by placing a plastic bag over the head.
Absorption through mucous membranes Absorption through mucous membranes (‘snorting’ or ‘snuffing’) is the method most commonly used with cocaine. The drug is sniffed into the nostrils, where it is absorbed. Injection Injection subcutaneously (‘skin-popping’, Figure 1) or intravenously (‘mainlining’, Figure 2) is the fastest method of delivering drugs to the brain in high concentrations. Intravenous injection is the route preferred by most abusers for the more potent opioid analgesics.
Hazards of abuse Accidental overdose is possible, though the degree of risk depends, to some extent, on the route of administration. Intravenous injection carries the greatest risk, because some users are inexperienced at injection technique and because there may be unexpected increases in the potency of street drugs. Because substance abuse is usually illegal, even unconscious or seriously ill individuals may not be referred immediately for medical help, and may be simply
Allister Vale is Director of the National Poisons Information Service (Birmingham Centre) and the West Midlands Poisons Unit at City Hospital, Birmingham, UK. He is a past President of the European Association of Poisons Centres and Clinical Toxicologists, past Trustee of the American Academy of Clinical Toxicology and President-elect of the British Toxicology Society.
MEDICINE
23
© 2003 The Medicine Publishing Company Ltd
TYPES OF POISONING
• bacterial infection of veins and heart valves • candidiasis • inadvertent intra-arterial injection, leading to digital gangrene (Figures 3 and 4).
Body-packing ‘Body-packing’ is the practice of smuggling drugs in small packets (condoms, foil and cellophane are commonly used) that are swallowed for later retrieval from vomit or faeces, or are inserted into the vagina or rectum. A surprisingly large number of packets can be concealed in this manner. Acute intestinal obstruction may result, and overdose is a hazard if a packet bursts. 3 A gangrenous forefoot resulting from intra-arterial injection of drugs.
Management • All patients suspected of body-packing should undergo abdominal radiography on presentation. CT of the abdomen should be arranged as soon as possible. • A urine screen for drugs of abuse should be performed on admission. A screen that is positive for one or more drugs suggests that either the patient has abused the drug in the previous few days, or at least one packet is leaking. A negative screen strongly suggests that no packet is leaking. Screens should be repeated daily, or immediately if the patient develops features of intoxication, to confirm the diagnosis. • Packets that remain in the stomach have been retrieved by endoscopy and by inducing emesis, but these are potentially dangerous procedures and are best avoided. • Optimal management of patients with packets in the small bowel is uncertain. If there is no clinical, analytical or radiological evidence to support leakage, the use of sorbitol or lactulose, with or without bowel stimulants (e.g. bisacodyl) to encourage transit through the gut, is successful in many cases. Alternatively, for faster results, whole-bowel irrigation using polyethylene glycol electrolyte solutions can be used. Liquid paraffin should not be used because it can weaken rubber, leading to bursting of the packets. Activated charcoal has been advocated by some, but induces constipation when used in substantial doses to surround a large number of packages, and is therefore contraindicated. • Packets in the colon or rectum are probably best managed by giving sorbitol or lactulose and allowing them to pass spontaneously, with least risk of rupture. • Immediate surgery is indicated if acute intestinal obstruction develops, or when packets can be seen radiologically and there is radiological, clinical or analytical evidence to suggest leakage, particularly if the drug involved is a CNS stimulant (e.g. cocaine). In this situation, the clinical consequences of poisoning are more serious and management is more difficult than for opioids (Brady et al. 1994) or cannabis. • Packets in the vagina can usually be removed manually and with ease.
observed by their fellow substance abusers until they improve or deteriorate so far that their condition can no longer be ignored. Irreversible brain damage may result. Contaminants Some complications of abuse result from deliberate addition of substances (e.g. quinine, talc) to dilute (‘cut’) the drug before it is sold. In other cases, preparations of the drug for injection (e.g. passage through cigarette filters or cotton wool) introduces contaminants. Particulate contaminants cause long-term, progressive granulomatous pulmonary lesions. Other contaminants, particularly quinine, may be responsible for some of the more acute toxic phenomena seen, and possibly even death. Other hazards Other hazards of drug abuse include: • infection with hepatitis B, C and D virus and HIV • injection site abscess caused by infection or leakage of drug into the tissues
Volatile substance abuse
4 Ischaemic hand and fingers resulting from intra-arterial injection of an opioid. The tourniquet had been placed round the palm of the hand, excluding the thumb. The injection was made into one of the digital arteries, under such pressure that the injected material was flushed back into the palmar arch, from where it was distributed to all the digits.
MEDICINE
Volatile substance abuse is the preferred term for the intentional inhalation of volatile substances (other than conventional anaesthetic agents). It replaces older terms such as ‘solvent abuse’ and ‘glue-sniffing’.
24
© 2003 The Medicine Publishing Company Ltd
TYPES OF POISONING
Commonly inhaled substances include: • toluene-containing glue • chlorinated hydrocarbons (cleaning fluid, paint, varnish, lacquer, dye) • fluorocarbons (aerosol propellant, fire extinguishers) • petrol (gasoline) • acetone (nail polish remover, polystyrene cement) • butane • propane • amyl, butyl and isobutyl nitrites (which may also be ingested). Volatile substances are usually bagged or huffed. Occasionally, aerosols are sprayed directly into the mouth (a particularly dangerous practice), or petrol is drunk mixed with cola or lemonade.
Management: treatment of acute volatile substance poisoning is supportive. It is occasionally necessary to sedate the abuser, to prevent personal harm and injury to others. Diazepam, 10 mg i.v., may be used. Methaemoglobinaemia (if concentration > 30%) should be corrected by intravenous administration of methylene blue, 1–2 mg/kg. Management of chronic volatile substance abuse is psychological rather than physical, in the hope that complications will reverse once abuse ceases.
Clinical features Acute intoxication – the clinical features of volatile substance abuse are similar to those of ethanol intoxication (initial CNS stimulation followed by depression). Features include euphoria, impaired judgement, feelings of omnipotence, blurring of vision, tinnitus, slurring of speech, ataxia and headache. Occasionally, a delirious state is seen, with clouding of consciousness and hallucinations. Convulsions, status epilepticus, respiratory depression and coma may ensue if inhalation of the volatile substance continues. Arrhythmias (e.g. asystole, severe bradycardia, ventricular fibrillation), which are thought to result from sensitization of the myocardium to endogenous catecholamines, are a significant cause of death. Inhalation of volatile nitrites may cause the additional problem of severe or even fatal methaemoglobinaemia. Chronic abuse – the hair, breath and clothing of chronic abusers may smell of solvent, and clothing is often stained by repeated bagging. Bagging may cause erythematous spots around the mouth and nose (‘glue-sniffer’s rash’). Abdominal pain, nausea, vomiting and haematemesis may be the presenting symptoms. Hepatic necrosis (alone or with renal failure) has been reported. School or work performance may be impaired as a result of apathy and poor concentration, and frank dementia has been observed in more severe cases. Toluene abuse characteristically causes cerebellar damage leading to ataxia, tremor, nystagmus and titubation. Pyramidal signs and cranial nerve damage (particularly hyposmia and optic atrophy) have also been reported, and cerebellar and cortical atrophy have been demonstrated by CT. Cerebellar signs may be partly or wholly reversible, however, with cessation of substance abuse. Muscular weakness may be profound, can present as quadriparesis and may mimic Guillain–Barré syndrome; severe hypokalaemia is common in such patients. Toluene and petrol (because of the presence of tetraethyl lead) may cause peripheral neuropathy. Haematuria, pyuria and tubular proteinuria are common in chronic toluene abusers. Renal failure may ensue. Renal tubular acidosis is well recognized, possibly resulting from the permeability of the distal tubule to hydrogen ions, leading to reduced ability to acidify urine. The hypochloraemic acidosis thus induced may be asymptomatic, or may present with severe muscular weakness caused by hypokalaemia or with urolithiasis secondary to hypercalciuria. High anion gap acidosis has also been reported. Dilated cardiomyopathy has been described rarely.
MEDICINE
REFERENCE Brady W J Jr, Stremski E, Eljaiek L et al. Freon Inhalational Abuse Presenting with Ventricular Fibrillation. Am J Emerg Med 1994; 12: 533–6. FURTHER READING Albertson T E, Walby W F, Derlet R W. Stimulant-induced Pulmonary Toxicity. Chest 1995; 108: 1140–9. Aldrighetti L, Pagnelli M, Giacomelli M et al. Conservative Management of Cocaine Packet Ingestion: Experience in Milan, the Main Italian Smuggling Center of South American Cocaine. Panminerva Med 1996; 38: 111–16. Brady W J Jr, Stremski E, Eljaiek L et al. Freon Inhalational Abuse Presenting with Ventricular Fibrillation. Am J Emerg Med 1994; 12: 533–6. Cox M J, Hwang J C F, Himel H N et al. Severe Burn Injury from Recreational Gasoline Use. Am J Emerg Med 1996;14: 39–43. Marelich G P. Volatile Substance Abuse. Clin Rev Allergy Immunol 1997; 15: 271–89. Martinez J S, Sala J J G, Vea A M et al. Renal Tubular Acidosis with an Elevated Anion Gap in a ‘Glue Sniffer’. Hum Toxicol 1989; 8: 139–40. O’Donnell A E, Selig J, Aravamuthan M et al. Pulmonary Complications Associated with Illicit Drug Use. Chest 1995; 108: 460–3. Shannon M. Clinical Toxicity of Cocaine Adulterants. Ann Emerg Med 1988; 17: 1243–7. Sporer K A, Firestone J. Clinical Course of Crack Cocaine Body Stuffers. Ann Emerg Med 1997; 29: 596–601. Steffee C H, Davis G J, Nicol K K. A Whiff of Death: Fatal Volatile Solvent Inhalation Abuse. South Med J 1996; 89: 879–84. Tenenbein M. Leaded Gasoline Abuse: The Role of Tetraethyl Lead. Hum Exp Toxicol 1997; 16: 217–22. Young S J, Longstaffe S, Tenenbein M. Inhalant Abuse and the Abuse of Other Drugs. Am J Drug Alcohol Abuse 1999; 25: 371–5.
25
© 2003 The Medicine Publishing Company Ltd