Abuse of Drugs Flashcards
Agent Factors:
Factors that influence the likelihood that a beginning drug user will lose control and develop an addiction
Availability of drug
Cost
Potency
Mode of administration
Speed of onset and term. of effects (pharmacokinetics)
Host Factors:
Factors that influence the likelihood that a beginning drug user will lose control and develop an addiction
Genes: Innate tolerance, speed of developing acquired tolerance, likelihood of experiencing intoxication as pleasure
Metabolism of drug
Psych symp.
Prior experiences
Tendency to take risk-taking behaviour
Environment Factors
Factors that influence the likelihood that a beginning drug user will lose control and develop an addiction
social setting
community attitudes
other sources of pleasure
employment/education
environmental cues
Which two neural pathways are most affected by drugs of abuse
Dopamine (eg. mesolimbic pathway) and serotonin
A student is found at a party with depressed level of consciousness preceded by euphoria
On examination :
Pupillary miosis
Conjunctival injection
Injection sites identified on arms
Decreased respiratory rate and bradycardia
Absent bowel sounds (constipation)
What drug is most likely involved?
Opioid
Miosis is giveaway
What are symptoms of opioid OD
respiratory depression and failure
bradycardia
hypovolemia
pulmonary oedema
coma
aspiration pneumonia
rhabdomyolysis
What are typical u-opioid receptor characteristics
cause euphoria, inhibit GABA neurons
What are typical characteristics of k-opioid receptors
dysphoria, inhibit dopamine neurons
What is more potent, heroin or morphine
Heroin (also greater availability)
How is Heroin administered
IV, IM, subcut, inhaled, smoked
What are some of the signs of Opioid withdrawal
Signs generally opposite of those induced by the drug
Nausea, vomiting, diarrhoea
Insomnia, myalgia (treat by giving u agonists)
Sweating, mydriasis, lacrimation, rhinorrhoea, agitation
Tachycardia, raised BP
What is the treatment of Opioid withdrawal?
Naloxone
Naltrexone
What is the difference between Naloxone and Naltrexone
Naloxone: Acts within minutes (life-saving). Good for acute cases of intoxication
Naltrexone: Longer duration of action, better for long-term management of opioid and alcohol dependence
What are some of the benefits of methadone
substitute for suppressing heroin withdrawal syndrome as it reduces pain to tolerable level like morphine but does not produce euphoric symptoms
A student presents to the EC, anxious with hallucinations and tachycardia
What drug was most likely taken?
Weed
Cannabinoids characteristics
THC: long terminal half-life, euphoria and relaxation (fast-onset)
THC essentially disinhibits dopamine neurons (inhibits GABA neurons in VTA)
Abrupt cessation symptoms of exogenous cannabinoids
Restlessness
Irritability
Agitation
Insomnia
Cramps
Dependence on exogenous cannabinoids symptoms
Heavy daily use: panic attacks, acute psychosis, hallucinations
How do you treat Cannabinoid severe reaction?
Benzo
24 year old female attended a new years party. She had multiple alcoholic beverages to drink:
An hour later she was euphoric, elated and socially disinhibited. Later that evening experienced difficulty with balance and muscle co-ordination.
According to her friend she started behaving more erratic and vomited twice. Following that she became comatose and required intubation when the paramedics arrived.
What is the most likely drug involved
Alcohol
Alcohol poisoning signs
Hypothermia
hypoglycaemia (especially in children)
metabolic acidosis
electrolyte disturbances
cardiac arrhythmias may also occur
aspiration of vomitus may result in pneumonitis and pulmonary oedema
Vomiting from alcohol’s disruptive effect on the semi-circular canalsof the inner ear and chemical irritation of the gastric mucosa.
Blood ethanol levels above 400 mg% (87 mmol/L) may be fatal. (The potential lethal dose of ethanol in the non-tolerant adult is 5 – 6 g/kg and 3 g/kg for children.)
Chronic ethanol abusers may survive considerably higher blood ethanol levels
