Drugs of Abuse Flashcards
What are abused substances?
Substances taken repeatedly that interfere with daily life / wellbeing
What are the main classes of abused drugs (5)
Sedatives
Opioids
Stimulants
Hallucinogens
Cannabinoids
What do most addictive substances have in common?
They increase dopamine in the limbic system
What are the psychological components of drug dependency?
Drug seeking behavior
What are the physiological effects of drug dependency
Quitting produces symptoms opposite of sought-after effects (withdrawal)
What percentage of Canadians consume alcohol and what % are high-risk drinkers?
76% have drank in the past year
44% are high risk
What % of Canadians use cannabis?
21%
Cannabis and alcohol use is higher in ____ than _____
Higher usage of alcohol and weed in men
What are the 3 steps to the therapeutic approach to drug abuse?
- tread the acute overdose
- Manage the withdrawal symptoms
- Long-term rehabilitation
Sedatives include drugs such as… (3)
Ethanol, barbiturates, benzodiazepines
What are the symptoms of sedative withdrawl?
Tremors, anxiety, vomiting, sweating, perceptual distortion
Withdrawal often occurs from which 2 sedative types?
Ethanol and barbituates
How do doctors manage sedative withdrawal symptoms?
Clonidine - helps with autonomic withdrawal symptoms
Benzodiazepines - helps with ethanol withdrawal
You can develop a tolerance to sedatives but not their…
Cant become tolerant to sedative respiratory depressant effects
What causes alcohol tolerance?
The Microsomal ethanol oxidizing system (MEOS) plays a role in ethanol metabolism
Ethanol -> acetaldehyde
Chronic alcohol use increases the rate that MEOS can breakdown ethanol requiring more alcohol in system for desired effects
What are opioids?
Drugs that offer a rush followed by a euphoric feeling and then sleepiness.
All come from the opium poppy
What are examples of opioids?
Morphine and heroin
What is the mechanism of action of opioids?
They interact with the opioid receptor (mu) which is linked to G-protein
What is the presynaptic effect of opioids?
They reduce presynaptic Ca+2
This reduces neurotransmitter release
What is the postsynaptic effect of opioids?
They increase potassium levels
This inhibits postsynaptic neurons
Tolerance of opioids is often built through…
pharmacokinetic changes and pharmacodynamic changes to the user
ex. increased metabolism and receptor sensitivity
Opioids are more addictive when taken…
for recreational use over analgesic use
The effects of heroin last ___ meaning…
heroin lasts 3-5 hours meaning several doses are needed to prevent withdrawals
Heroin comes in many formulations, this is dangerous because…
Different forms have different potencies (overdose risk is high)
What are the 3 methods of administering heroin?
Inhalation
Sub-cutaneous
IV
What are the symptoms of heroin overdose? (3)
Respiratory depression
Coma
Death
What is an opioid receptor antagonist?
Naloxone
What are some medications used as opioid detoxifiers?
Methadone - an oral long-acting mu antagonist
Clonidine - helps with autonomic symptoms of withdrawal
What are some examples of stimulants?
Amphetamine and cocaine
Stimulants are ____ addictive and very _____
Stimulants are highly addictive and very dangerous
Amphetamines ____ the release of dopamine, serotonin and NE
Amphetamines increase the release of dopamine serotonin and NE
Cocaine reduces the ____ of dopamine, serotonin, and norepinephrine
Cocaine reduces the reuptake of NE, Dopamine, and serotonin
How is tolerance for stimulants developed?
Likely due to dopamine receptor sensitivity
What are the desired effects of stimulants?
Alertness and euphoria
What are the adverse effects of stimulants?
Psychosis, delusions, excess sympathomimetic activity
What are the overdose effects of stimulants
Intracranial hemorrhage, seizures, arrhythmia, heart attack, hyperthermia, coma and death
Amphetamines are _____ than cocaine
often less commonly fatal
What are 2 commonly abused hallucinogens?
LSD and PCP
What is the technical term for LSD?
Lysergic acid diethylamide
What is the technical term for PCP
phencyclidine
What is the method of action for LSD?
Agonist for several 5-HT receptors
most are partial or complete agonists of 5-HT2a receptor
What is the method of action of PCP?
It is an NMDA receptor antagonist
Is there tolerance and dependency with hallucinogens?
Tolerance is very short term and dependency is very rare
What are the desired effects of hallucinogens
Visual illusions and perceptual distortions
What are the adverse effects of hallucinogens?
Panic attacks, psychosis, flash-backs, SNS symptoms
Is it possible to overdose on LSD?
the therapeutic index is very large so it would be really hard to
Is it possible to overdose on PCP?
yes, possible and easy due to its low therapeutic index
What are 2 common names for cannabinoids?
Marijuana and hashish
What is the psychoactive component of cannabinoids?
THC “tetrahydrocannabinol”
What is the method of action for cannabinoids?
Cannabinoid receptors -> linked to Gprotein -> inhibit GABA or glutamate release
What are the 2 cannabinoid receptors?
CB1 - Central nervous system
CB2 - Peripheral nervous system
What are the initial effects of cannabinoid use?
Initial effects: euphoria, laughter, altered sense of time
What are the secondary effects of cannabinoids?
Relaxation, introspection, sleepiness
What are some of the “negative” effects of cannabinoids?
Impaired cognition, impaired reaction time potential paranoia, anxiety, and hallucinations
What are the negative results of cannabinoid use?
Bronchitis and lung cancer
What are the therapeutic uses of marijuana?
Decreased pain, nausea, and vomiting in cancer patients
Increased appetite in aids patients
