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JamesBoyd

Identification of Illegal Drug Overdose and Diagnosis of Illegal Drug Poisoning

Overdosing on illegal drugs is usually accidental. Suicide attempts are rare.
In adults, severe poisoning practically always represents mixed poisoning, usually involving hypnotics, sedatives and alcohol.
- Users do not necessarily know what they have taken.
- Illegal drugs may contain something other than was believed; contents and concentrations may vary.
Users of illegal injection drugs often have blood-transmitted infections, such as hepatitis or HIV.
Injection may be associated with vascular or nerve injury or acute infections.
- Due to vascular damage, it may be difficult to establish vascular access.
Treatment may be delayed due to fear of the police or attempts to use "home remedies", such as cold baths.
Notice that there may be country-specific or regional differences in the availability and frequency of use of different substances and consequently various types of overdosing incidents.

The illegal drugs most often encountered in initial treatment and emergency services treating overdose are, in order of frequency:
- gammabutyrolactone (GBL) / gammahydroxybutyrate (GHB) (G, Gina, Liquid E, Liquid Ecstasy)
- opioids, particularly buprenorphine
- amphetamine and similar designer drugs
- hallucinogenic agents, such as phencyclidine derivatives.
For financial benefit, illegal drugs can be mixed or cut with substances that are toxic themselves.
Ingested packets may leak or cause delayed poisoning.
- Packets swallowed hastily in association with arrest, for instance, leak more easily than packets that were well packed for smuggling.

Opioids, in particular buprenorphine, benzodiazepines and pregabalin, for instance, can be abused.
People may try to extract or separate drugs from pharmaceutical products, such as combinations of paracetamol and codeine, fentanyl patches and cough medicines.
Counterfeit prescription drugs may look genuine but may contain designer drugs, for instance, such as designer benzodiazepines or opioids.

CNS stimulants include:
- phenethylamines (amphetamine-type, many designer drugs, recreationally used ADHD medication, such as methylphenidate)
- cocaine (including crack and free base cocaine).
The effects of CNS stimulating drugs (see T1) are mainly based on increased secretion or inhibited reuptake at nerve endings of catecholamines, in some cases also of serotonin.
It may be difficult to distinguish between different sympathomimetics based on their acute effects.
The effect of cocaine is usually briefer than that of amphetamines (tens of minutes vs. tens of hours).

The most common CNS depressants are gammabutyrolactone/gammahydroxybutyrate (GBL/GHB, G, Liquid E), opioids, and illegal and prescription drugs.
- Hallucinogenic agents, such as phencyclidine, may also have CNS depressant effects.

In illegal drug overdose, the problem is usually a decreased level of consciousness and respiratory depression and, more rarely, symptoms and findings associated with sympathomimetic toxicity; see Table T2.
In addition to displaying needle marks, patients may possess:
- needles, syringes, pipes or other drug paraphernalia
- powder, granules or paste in small bottles or wrapped in plastic, plastic film or foil.

There is no reliable bedside test for diagnosing overdose of illegal drugs.
Saliva or urine drug tests are screening tests and not diagnostic.
- They may give false positive or false negative results.
- Positive results must be confirmed by a blood test and, in practice, it will take several days, at least, to obtain the results.
- The tests cannot identify several designer drugs, for instance.

The treatment of poisoning is symptomatic.
See Treatment of Poisoning for details.
Ensure airway patency, oxygenation and ventilation aiming for SpO₂> 95% and prevention of aspiration.
A convulsive seizure is a sign of severe poisoning and should be treated with a benzodiazepine http://www.dynamed.com/condition/seizure-in-adults#BENZODIAZEPINES_FOR_SEIZURE_CESSATION.
If there is hyperthermia, external cooling should be started by undressing the patient and removing any covers.
- Agitation and muscle activity can be reduced by sedation (benzodiazepines).
- Physical restriction, such as restraints, should be avoided because it typically increases agitation.
The specific antidotes for opioid and benzodiazepine poisoning are naloxone and flumazenil, respectively. However, when using these it should be noted that reversing the effects of an opioid or benzodiazepine completely may be fatal in the case of mixed poisoning where the depressant effects of one agent protect the patient from the toxicity of another (e.g. stimulant + opioid) http://www.dynamed.com/management/benzodiazepine-toxicity-emergency-management#THERAPY.
- Administer carefully, monitoring the response

Benzodiazepines should be given without hesitation http://www.dynamed.com/condition/acute-intoxication-from-stimulant-and-hallucinogen-drugs#TOPIC_KKM_VMV_P4B.
The use of beta blockers involves risks.
In the case of severe poisoning, any organ system may be damaged but monitor particularly for impaired liver and kidney function and rhabdomyolysis.

Neuropsychiatric effects	Euphoria
	Motor restlessness, trismus and bruxism, convulsions
	Anxiety, sleeplessness
	Anorexia
	Confusion, agitation and delirium
	Hallucinations, and paranoia, in particular
	Headache
Sympathomimetic effects	Tachycardia, other arrhythmias, hypertension
	Mydriasis
	Sweating
	Tachypnoea
	Tremor
	Nausea
	Vasospasms, acute coronary syndrome
	Cerebrovascular disturbances
	Arterial dissection
Activation of the serotonin system	A feeling of unity and empathy
	Raised body temperature, even thermoplegia
	Hyperthermia Particularly the phenethylamines ecstasy (MDMA), PMA and PMMA
Other possible effects and findings	Cocaine increases platelet aggregation and as a local anaesthetic blocks sodium channels. Causes myocardial hypoxia, arrhythmias and convulsions, for instance, more readily than amphetamines do. In the case of massive cocaine overdose, local anaesthetic poisoning
	Rhabdomyolysis
	Hyponatraemia
	Hyperglycaemia
	Kidney and/or liver failure
	Pulmonary oedema of non-cardiac origin
	Metabolic acidosis
	Ischaemic colitis
	Blood coagulation disorders (DIC)
	Obstetric complications, such as miscarriage
Withdrawal symptoms	No physical withdrawal symptoms
Withdrawal symptoms	Tiredness, fatigue and depression may occur.

CNS depressants	Symptoms and findings	Decreased level of consciousness, respiratory depression
		Hypothermia
		Aspiration pneumonia
		Rhabdomyolysis
	Differential diagnosis	Sepsis, meningoencephalitis or other severe infection
		Hypoglycaemia, hyponatraemia
		Hypoxic ischaemic brain damage, craniocerebral trauma or spontaneous cerebral event
		Nonconvulsive status epilepticus, psychogenic non-epileptic seizure
		Severe hypothermia
CNS stimulants	Symptoms and findings	Aggressive and disoriented behaviour, "excited delirium"
		Hyperthermia, thermoplegia
		Hypertensive crises or arrhythmias in young, previously healthy people
		Convulsions
	Differential diagnosis	Psychiatric disease without drug abuse
		Spontaneous intracranial haemorrhage or craniocerebral trauma
		Hypoglycaemia
		Meningoencephalitis