Test 1 (Chapters 1-5) Flashcards
What is a drug?
Any chemical entity or mixture of entities, other than those required for the maintenance of normal health (like food), the administration of which alters biological function and possibly structure.
Drug use vs drug abuse
Depends on relationship a person has with that drug as well as dose, frequency of use, and occurrence of adverse outcomes.
Factors that shape our attitudes about drugs.
Drugs effect, time place and reason for taking the drug, demographic characteristics of the user.
Drug addiction
A condition of compulsive drug seeking and drug use despite the harmful consequences associated with drug use, and it includes long-term changes to brain structure and function.
Substance use disorder
The diagnostic label for drug addiction currently preferred in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (also known as the DSM-5)—is diagnosed based on the presence of key indicators of problematic drug use. (ex withdrawal symptoms, drug causing problems in relationship, spending time getting and using drug)
Global Drug Use
The prevalence of drug use is not simply related to a country’s drug policies.
Canadian Student Tobacco, Alcohol and Drugs Survey (CSTADS, formerly the Youth Smoking Survey)
Drug use is lowest for ages 15–19, is substantially higher for ages 20–24 (highest), and begins to decrease for ages 25+. Alcohol is most used. Measured biannually.
Gender differences in drug usage
Men are more likely to use illicit drugs than are women. Men more likely to be destructive and engage in devious behaviours.
Education
The use of specific drugs often covaries with the amount of formal education one has.
Why Do People Use Drugs?
To Feel Pleasure and to Avoid Feeling Pain, To Change the State of Consciousness, To Enhance Spiritual, Religious, or Mystical Experiences, To Facilitate and Enhance Social Interactions, To Alter and Improve the Body
With respect to Judeo-Christian religions (i.e., Judaism, Christianity, and Islam), which statement best summarizes the evolution of the relationship between alcohol and these religious practices?
Alcohol played a role in the development of all three religions, but over the years, over-consumption, and in some denominations, any consumption at all, has become prohibited.
Risk factors
The personal characteristics of, or environmental influences on, an individual that increase the likelihood of drug use.
Protective/resiliency factors
decrease the likelihood of drug use
Individual Problems with Acute Use
-Drug administration can be problematic
-Drug impurities
Drug Misuse
When an individual takes medicine prescribed to them in a manner inconsistent with the prescription.
Individual Problems with Chronic Use
-Chronic health problems including psychiatric problems
-Problems with personal relationships, occupation, and financial status.
-Legal problems
Societal Problems Associated with Drug Use
-In Canada, substance use is estimated to cost almost $40 billion annually, when considering health care expenses, lost productivity, and criminal justice costs.
-About 70 per cent of these costs are due to alcohol and tobacco.
-Drug-related violence, car accidents, or fetal harm.
The increased crime and incarceration
-Illicit drug manufacturing and use can cause environmental damage through toxic waste or infected needles.
Illegal vs Illicit drugs
Illegal drugs are drugs that are restricted by laws. Illicit drugs may be forbidden by laws, rules, or customs, but they are not necessarily illegal. For example, underage drinking may be considered illicit use, even though alcohol is not illegal when used properly.
Endogenous substance
Produced within an organism. Examples: endorphins are endogenous forms of morphine, anandamide is our body’s natural form of cannabis.
What are Naturally occurring drugs+what percentage of drugs are naturally occuring
About 50 per cent of all medicines on the market are derived from what are called natural products, molecules produced by living organisms for a variety of functions.
Drug Naming
After a patent application has been filed for a drug, it is given a generic name (its official name, not capitalized) and a brand or trade name (capitalized), which is used by the company that has filed the patent for the drug.
Three sources of drug development
- The rediscovery of traditional uses of various naturally occurring products
- The accidental observation of an unexpected drug effect
- The synthesis of known or novel compounds
Health Canada Drug Development and Approval
-Pre-clinical stage (2-10yrs)
-Clinical Stage(6-7yrs)
-Health products and food branch (HPFB) Review
-Post-marketing analysis
Direct-to-consumer (DTC) advertising
Pharmaceutical companies market their products directly to patients rather than to health care professionals. Ads often describe a disease and then tell the viewer about the specific drug that can treat it. Canada only allows reminder ads that state the drugs name and disease-oriented and help-seeking ads, which do not advertise a specific brand but describe a condition and encourage consumers to ask their doctors about treatment.
Links between exposure and drug consumption
- People are wired to imitate other people’s behaviours.
- Viewers observe beautiful, glamorous actors and musicians using alcohol and other drugs and learn to idealize their use.
- Media references also might teach people to associate drugs and alcohol with certain behaviours, such as champagne on New Year’s Eve.
Physical dependence
reflects the changes that occur when the body and brain adapt to the presence of a drug, requiring increasingly higher amounts of the substance to achieve the desired effect (tolerance) and producing drug-specific symptoms when drug use is terminated (withdrawal). Although it often accompanies addiction, physical dependence alone does not constitute addiction.
Psychological dependence
is the state of strongly craving a drug. People may be psychologically dependent on a drug if they compulsively use it for its positive effects or to experience relief from stress or emotional discomfort. Psychological dependence can be even more powerful than physical dependence.
Addiction
the compulsive use of and preoccupation with a substance such that it causes physical, psychological, and/or social harm to the user.
Capture ratio
the percentage of those who try a drug and become habitual users, may be influenced by legality. Highest is nicotine, then heroin, crack cocaine, powder cocaine, alcohol
In terms of addiction, which statement most accurately describes how we tend to think about and categorize addiction, as opposed to how physical dependency on a drug actually works?
We are less likely to use the term addiction to describe legal, prescribed drugs that people are reliant upon for medical reasons, such as high blood pressure medication or insulin.
What are two of the telltale signs of psychological addiction?
A very strong subjective craving for a drug without a physical need for it and compulsively using it to alleviate or avoid emotional discomfort correct
How many Canadians meet the criteria for a substance use disorder at some point in their lives
21.6%
_______ is a broad category which refers to and includes the misuse, dependence, and addiction to alcohol, legal, and/or illegal drugs.
Substance use disorders
Among Indigenous communities, deaths due to alcohol are _______ times as high as the general population.
two
Among the elderly, substance abuse can be particularly difficult to diagnose because
the symptoms can mimic other medical and behavioural conditions
spontaneous remission
when people quit drugs on their own without intervention, most people quit this way.
Components to addiction
- Preoccupation
- Mood modification
- Tolerance
- Withdrawal
- Conflict
- Relapse
Criteria for Substance Use Disorder from DSM-5
Impaired control, social impairment, risky use, pharmacological dependence
Addiction Severity Index (ASI)
The ASI is an hour-long, semi-structured interview used to gather information about recent and lifetime problems in six key areas of the user’s life:
- medical status
- employment and support
- alcohol and other drug use
- legal circumstances
- family and social relationships
- psychiatric status
CAGE strategy
C: Have you ever felt the need to Cut down on your drinking? A: Have you ever felt Annoyed by someone criticizing your drinking?
G: Have you ever felt Guilty about your drinking?
E: Have you ever felt the need for an Eye opener (drink at the beginning of the day)?
When it comes to genetics and addiction, which statement below is the most accurate given the current data?
It appears that genes predispose some people to have a greater risk of becoming addicted to drugs; however, a predisposition does not remove a person’s choice in terms of decisions and behaviours.
How does Drug addiction affect/related to Prefrontal cortex
The prefrontal cortex controls many things, including the ability to regulate emotions, suppress urges, and make decisions. With long-term drug use, normal baseline activity of the orbitofrontal cortex shows reduced activity, which may allow impulsive behaviours to override rational decisions. However, activity in the dorsolateral prefrontal cortex, an area that regulates cue-related cravings, may be increased.
How are Hippocampus and Drug addiction related
The hippocampus, involved in learning and memory, may play a role in addiction. When people begin using drugs, the action (finding and taking drugs) leads to a particular outcome (feeling good). The user learns to associate the positive feelings produced by the drugs with the drug paraphernalia used and with the environment in which it occurs. Over time, these drug cues produce greater responses in the reward pathways than the drugs themselves. This associative learning is mediated, in part, by the hippocampus, which becomes sensitized, and drug seeking becomes compulsive.
Drug addiction and The “pleasure centre”: ventral tegmental area (VTA)/nucleus accumbens (NAc)
a functional deficiency of the dopaminergic neurons projecting to “pleasure centres” of the brain—leading to diminished subjective feelings of intoxication or pleasure
Drug addiction affects on neurotransmitters (dopamine)
Dopamine is considered to be the primary neurotransmitter of reward and motivation. As far as we know, all drugs of abuse increase dopamine transmission in the NAc, amygdala, hippocampus, and prefrontal cortex. Long-term, chronic exposure to addictive drugs changes these dopaminergic pathways so that they are less responsive to rewarding stimulation.
Genetic Factors Underlying Addiction+what % of addiction can be attributed to genes
An individual’s risk of drug addiction increases if they have a parent or sibling who is dependent on drugs or alcohol. But addiction is a complex phenomenon, and there is no single “addiction gene” that controls it. Multiple genes and environmental factors interact to affect a person’s susceptibility to drug addiction. Family studies of addiction suggest that perhaps 40–60 per cent of one’s predisposition to addiction can be attributed to genes.
Epigenetic factors of drug addiction
inherited modifications in gene expression caused by environmental factors—also play an important role in the development and maintenance of drug addiction and may be one of the missing links between environmental stimuli and genetic inheritance.
Psychological and Interpersonal Factors affect:
affect the likelihood of addiction. Certain personality traits are associated with a higher risk of alcohol or drug addiction. Impulsiveness, rebelliousness, and sensation-seeking can raise one’s risk, as can insecurity, poor self-esteem, and a lack of resilience.
Social and Environmental Factors of drug addiction
Social and environmental factors powerfully affect addiction. Drug addiction is often heavily concentrated in the poorest communities. Poverty, racism, and occupational stress are associated with higher rates of addiction, as are communities that have reduced opportunities for employment, education, and cultural outlets.
_______ is a neurotransmitter involved in learning and memory, but it also plays an important role in addiction because it makes the hippocampus and frontal lobe hypersensitive to drug cues.
Glutamate
Genetic factors for drug abuse seem to be stronger in _______, who also show higher heritability to specific drugs—namely _______.
males; heroin and cocaine
In studying attitudes about addiction among addiction educators, researchers found that higher levels of education and experience on the job leads to
less support for the idea that addiction is a disease and that people are genetically predisposed to be addicts from birth. Researchers found that addiction educators, especially those who do research in the field, strongly believe that addiction is a coping mechanism for dealing with stressful life situations or psychiatric issues.
1908 Opium Act
- This Act was the first law to allow the government some oversight of the drug marketplace.
-Opium smoking had been growing in popularity in Canada since the mid-1850s, particularly among Chinese labourers. And although the government benefited from the taxation of opium and the factories that produced it, increasing concern about Chinese labourers taking jobs away from Canadians and ultimately a riot in Vancouver’s Chinatown motivated the implementation of this Act.
-The Act banned the importation, manufacturing, possession, and sale of opium. These were not (yet) imprisonable offences.
1908 Proprietary and Patent Medicine Act
Patent medicines were untested medical cures for everything from coughs to menstrual cramps in the late 1800s and early 1900s. These products commonly included opium and cocaine, often in very high concentrations (although you wouldn’t know it, as prior to this Act there were no requirements to list the ingredients of a product on its label). This Act banned the use of cocaine in patent medicines and required pharmaceutical companies to list opium, morphine, or heroin on the product label if any of these were ingredients.
1911 Opium and Drugs Act
This Act banned the importation, manufacturing, possession, and sale of opium, morphine, and cocaine. Imprisonment was introduced as a penalty
1916 to mid-1920s Alcohol Prohibition
During World War I, most provinces instituted a ban on alcohol. The year Prohibition came into effect varied from one province to the next, and Prohibition was repealed in each province, typically within 5–10 years. (except Quebec which was short and PEI which was 40 years)
1923 Act to Prohibit the Improper Use of Opium and Other Drugs
This update of the 1911 Opium and Drugs Act added cannabis to the list of drugs already banned (opium and cocaine). Emily Murphy, a female judge was central to the criminalization of cannabis through her racist beliefs and writings. In her book The Black Candle (1922), Murphy created propaganda about members of non-White races using cannabis to “bring about the downfall of the White race.” These writings further perpetuated the racist panic that criminalized other drugs
1929 Opium and Narcotic Drug Act
This Act increased penalties for drug users and doubled the penalties for drug trafficking from 7 to 14 years. It served as Canada’s main drug policy for more than 30 years.
1961 Narcotic Control Act
This Act banned possession, trafficking, importing, and exporting of narcotics, including opiates, cocaine, and cannabis.
1969 (through 1972) Commission of Inquiry into the Non-medical Use of Drugs (also known as the Le Dain Commission)
-Canada’s drug laws were resulting in a lifetime of barriers to personal freedom to those convicted, disproportionate to the harms of the drugs
-The Pierre Trudeau government ordered the Le Dain Commission to carefully examine the use of narcotics and associated penalties.
-The Le Dain Commission, whose recommendations recommended gradually decriminalizing all illicit drugs and enacting a fine of $100—and zero jail time—for possession of any illicit drug.
-also recommended removing cannabis from the Narcotic Control Act
-It further argued that scientific evidence should drive drug policy
-None of the commission’s recommendations were implemented.
1996 Controlled Drugs and Substances Act
This Act classified illicit drugs and their precursors into eight schedules. Punishments for trafficking opiates, cocaine, and other Schedule I drugs, as well as trafficking cannabis (Schedule II), were increased to a maximum of life imprisonment. Punishments for the possession of small amounts (less than 30 grams) of cannabis were decreased.
2001 Marihuana Medical Access Regulations (MMAR)
This law permitted Canadians access to cannabis for medical purposes. Medicinal cannabis is effective in treating specific conditions (multiple sclerosis, a spinal cord injury, or a spinal cord disease; severe pain)
2016 Canadian Drugs and Substances Strategy
The Canadian Drugs and Substances Strategy is Canada’s current evidence-based, compassionate, and public health–oriented approach to addressing problematic drug use through drug policy. The strategy is led by the Minister of Health and supported by Health Canada.
The four pillars of the Canadian Drugs and Substances Strategy
- The prevention pillar supports and implements evidence-based initiatives to increase awareness of the risks of substance use
- The treatment pillar supports evidence-based treatment options
- The harm reduction pillar supports measures that reduce the negative health, social, and economic effects of substance use
- The enforcement pillar increases the capacity of law enforcement to target organized crime
2018 Cannabis Act
The Cannabis Act came into effect on October 17, 2018, thereby legalizing cannabis in Canada. This was the most significant reversal of drug criminalization in Canada in the last century. possess up to 30 grams of legal cannabis (it is still illegal to possess illegal cannabis!), have 4 cannabis plants.
3 main activities of Health Canada’s National Native Alcohol and Drug Abuse Program (NNADAP)
Primarily controlled by Indigenous stakeholders, works to reduce harmful alcohol and other drug use in Indigenous people.
1. Prevention
2. Intervention
3. Aftercare
Controlled Drugs and Substances Act (CDSA)
In 1996, Prime Minister Jean Chretien’s government signed the (CDSA) into law. The CDSA classifies drugs, their precursors, and devices to produce tablets and capsules into seven drug schedules (numbered I to IX—Schedules VII and VIII were repealed with cannabis legalization)
When the World Health Organization (WHO) surveyed over 85,000 subjects in 17 countries about their drug use, what did the data indicate?
Countries with harsher drug policies did not have lower levels of drug use.
Harm Reduction Policies
Seek to reduce the health risks associated with drug use, reduce the overcrowding of prisons, and focus on treatment rather than punishment.
In 2003, Insite, the first-ever supervised consumption site (SCS) in North America, opened in Vancouver, British Columbia. How many onsite drug overdoses have been reversed since it opened?
Over 5,000
Approximately _______ of the prison population in Canada are incarcerated for drug offences, whereas approximately _______ of the prison population in the United States are incarcerated for drug charges.
7%; 50%
_______ drug crimes are those committed when drug laws themselves are violated (possession, trafficking, etc.).
Systematic
Members of the Independent Scientific Committee on Drugs rated 20 different drugs on 16 criteria related to the harms that the drug produced in the user and to others. What did their analysis reveal as being the least harmful drug(s)?
Mushrooms and LSD
In a survey conducted in 2018, what percentage of Canadians reported that they felt the government should consider the legalization (with regulation) of all drugs for personal use?
75%
What is a Teratogen
substance that interferes with normal fetal development and causes congenital disabilities. (aspirin, Accutane, phenytoin)
In Canada, a blood-alcohol concentration (BAC) of _______ is considered legally impaired; however, in most provinces, penalties are levied at a BAC of _______ or higher, with zero tolerance for novice drivers and commercial drivers.
0.08; 0.05
Neurons
cells that process and transmit information to aid communication throughout the body. They receive and integrate vast amounts of information from both the outside world and the internal environment, and they change constantly to adapt to the body’s demands, sensations, and environmental influences.
Sensory neurons
carry information into the brain and spinal cord
motor neurons
transmit signals from the brain and spinal cord out to our muscles, nerves, and glands in order to produce a response.
Neurogenesis
production of new neurons
Neuroglia
account for up to 90 per cent of brain tissue, provide neurons with nutrients and oxygen, clean up debris, protect and insulate neurons, and aid in the transmission of information.
soma
cell body, contains the neuron’s machinery, which keeps it functioning. The soma includes the nucleus, containing genes that code for proteins such as neurotransmitters and enzymes, as well as other organelles that keep the cell operational.
axon
the long, wire-like component of the neuron. Neurons have only one axon, but the axon can split into numerous branches called collaterals. The axons of most neurons are covered by a white, fatty substance called myelin, which by electrically insulating the axon speeds electrical transmission. There are gaps along the axon that are not covered by myelin called nodes of Ranvier and are the site of electrical signal generation.
axon terminal
where electrical signals travel to, contain sacs called vesicles which release neurotransmitters
Dendrites
branched outgrowths from the soma. Most of a neuron’s receptors (proteins with specific sizes, shapes, chemicals, and electrical properties) are located on the dendrites.
Choose the term which best matches the function associated with the following: _______= transmission; _______= messenger; _______= insulation; _______= receiver.
axon; neurotransmitter; myelin; dendrite
resting membrane potential
difference in voltage between the inside and outside of the neuron
Action Potentials
Information travels down an axon as a change in membrane voltage, then experiences depolarization
Pre and Post Synaptic neuron
The neuron that releases neurotransmitter is called the presynaptic neuron, and the neuron that the neurotransmitter affects is called the postsynaptic neuron.
ionotropic and metabotropic receptors
Ionotropic are receptors that neurotransmitters or drugs can bind to, an ion channel. Conversely, substances can bind to receptors that are separate from ion channels called metabotropic.
Neuronal transmission is possible when there is a change in voltage between the inside and the outside of a neuron. This is referred to as
action potential
The route of a neurotransmitter during neuronal transmission is in the correct order
Packaged into vesicles → travels down the axon → reaches axon terminal → fuses with presynaptic membrane → released into synapse; binds to receptors at the postsynaptic neuron
Nicotine, THC, and morphine are all examples of drugs that have an excitatory effect by
binding to their corresponding receptor sites.
What happens when drugs have an Excitatory Effect on Receptor Activation
Increases synthesis of neurotransmitters,
Increases release of neurotransmitters,
Binds to receptor nicotine,
Blocks presynaptic autoreceptors,
Blocks reuptake of neurotransmitters,
Blocks enzymes that break down neurotransmitters
(Ldopa, ectasy, THC, prozac, cocaine)
What happens when drugs have inhibitory effects on brain
Decreases synthesis of neurotransmitters,
Decreases storage of neurotransmitters in vesicles,
Decreases release of neurotransmitters,
Blocks the receptor,
Stimulates presynaptic autoreceptors
central nervous system (CNS) and peripheral nervous system (PNS)
The brain and spinal cord together form the central nervous system (CNS). The peripheral nervous system (PNS) is made up of all the nerves going to and from the brain and spinal cord
The Peripheral Nervous System subcategories
Divided into somatic and autonomic nervous system. The somatic nervous system consists of neurons that carry sensory information into the CNS, as well as nerve fibres that carry motor signals from the CNS to skeletal muscle cells. The autonomic nervous system is a series of neurons that innervate muscles and glands for bodily function.
neuromuscular junction (NMJ)
The site at which motor neurons from the somatic nervous system innervate (stimulate) skeletal muscles
parasympathetic system
ordinary, restful situations. The functions of this system can be remembered by the letter D: Digestion, Defecation, Diuresis, Dozing, and Downtime. Fibres in the parasympathetic system are highly targeted and discrete. This allows the organs innervated by the parasympathetic system to work independently.
sympathetic nervous system
the “fight or flight” system. It helps to mobilize our bodies in case of emergency. You can remember the letter E for the functions of the sympathetic system: Emergency, Energy Expending, Exercise, Excitement, and Embarrassment. There is extensive communication among sympathetic fibres, which means that the initial signal can have a widespread effect. This is advantageous because it allows the whole body to mobilize in times of emergency. Pupils dilate (cocaine and stimulants but antidepressants do that as well)
blood brain barrier (BBB)
CNS capillaries that prohibit most water-coluable substances from entering the brain, fat soluable molecules can cross. Functional protection for the brain. BBB absent around area postrema, vomiting center
The _______ carries basic sensory information into our brains for processing and governs voluntary control of the skeletal muscle system, while the _______ deals with visceral sensations and controls the involuntary action of smooth muscles, heart muscles, and the glandular system.
somatic nervous system; autonomic nervous system
LSD mainly affects these two brain structures, both of which play a significant role in how we process sensory information.
Cerebral cortex and thalamus
The psychoactive effects which drug users experience consciously are largely a result of how drugs interact with _______ structures; the effects drugs have on our basic life-sustaining functions are a result of how a drug affects the _______; and the pathways of drug addiction are mainly concentrated in the _______.
forebrain; hindbrain; midbrain
Our brain has other senses beyond the basic five; for example, this sense helps us track where our body position is relative to other objects and how we are moving through space.
Proprioception
Which of these substances cannot pass through the blood brain barrier (BBB)? Nutrients, oxygen, most drugs, lipid-soluble drugs
Most drugs
The BBB is absent in this part of the brain, also known as the vomiting center, because the ability of this area to detect toxic substances in the blood serves as an important safety mechanism.
Area postrema
GABA
As many as 40 per cent of the synapses in the CNS use GABA as their primary neurotransmitter. GABA decreases the activity of neurons that it binds to, helps to regulate neuronal excitability in the CNS, affects memory, and decreases pain signals. Many drugs bind to the GABAA receptor. Barbiturates, such as phenobarbital, and benzodiazepines, such as Xanax, bind to the receptor.
Glutamate
Glutamate is not only an amino acid; it is also the major excitatory neurotransmitter in the CNS. Over half of all brain synapses release glutamate. Some of the drugs that bind to glutamate receptors include PCP, ketamine, ethanol, and dextromethorphan. When the dissociative anaesthetics PCP and ketamine bind to the receptor, they block the channel and prevent glutamate’s effects
Catecholamines
Dopamine, norepinephrine, and epinephrine are catecholamines. These neurotransmitters are structurally similar to one another and also have some similarities in their functions. Some drugs that increase the effects of dopamine and norepinephrine include cocaine, amphetamine, drugs that treat ADHD, and some antidepressant drugs.
Serotonin
serotonin is an inhibitory neurotransmitter found throughout the brain and body. Serotonin got its name from sero (blood) and tonin (tone) due to its effects on vascular tone.
Opioids
Drugs such as morphine, codeine, and heroin bind to opioid receptors.
Cannabinoids
In the late 1980s, scientists discovered that THC, one of the psychoactive substances in cannabis, bound cannabinoid receptors in the brain. Receptors do not exist in our brain on the off-chance that we might happen upon a plant and smoke it; if there are receptors in our brain for a substance, that means that our bodies produce a natural form of that chemical. Endocannabinoids are produced naturally by the body
catecholamines
a chemical that is made by nerve cells and used to send signals to other cells. Catecholamines are important in stress responses.
prescription antipsychotic medication.
cocaine.
amphetamine.
prescription ADHD medication.
Which neurotransmitter is likely to work more slowly and less directly on receptors within the brain, instead working to regulate the efficacy of other systems?
Oxytocin
_______ is the main inhibitory neurotransmitter in the brain and _______ is the main excitatory neurotransmitter.
GABA; glutamate
If you were looking for a major neurotransmitter to target that was involved in sleep but not very involved in mood function, which of the following is the best fit?
Acetylcholine
If you wanted to create a new drug that has inhibitory relaxant properties but is not as sedating and fast-acting as drugs in the benzodiazepine family, you might target this type of receptor.
GABA
Most of the body’s serotonin is located in the
Gut
Pharmacokinetics
study of how drugs are handled by the body—how they are absorbed into the bloodstream, distributed throughout the body, transformed into different chemicals, and excreted.
Bioavailibility
the degree to which the original drug dose reaches its site of action
Absorption
process by which drugs pass from the external world into the bloodstream. Many factors affect how well a drug is absorbed, including the dosage, its route of administration, whether the drug is fat-soluble (dissolves in fats or oils) or water-soluble
Distribution
the transport of drugs to their site(s) of action in the body
Metabolism
The process by which the body accepts a drug, alters it chemically, and prepares it for excretion is called biotransformation or metabolism. Metabolites are by-products of the biotransformation process: structurally modified forms of the original chemical.
Elimination
Drugs leave the body through the kidneys, GI tract, lungs, and skin. Drugs are eliminated either unchanged or after being metabolized into pharmacologically inert, water-soluble by-products.
Pharmacodynamics
the study of what a drug does to the body and the mechanisms by which it exerts its effects.
Agonist
An agonist is a drug that mimics the effects of a neurotransmitter. This effect can be excitatory or inhibitory. Agonists can work in a variety of ways. They may fit directly into the postsynaptic receptor (like a key in a lock) or they may increase the amount of neurotransmitter in the synapse. A partial agonist is a chemical that binds to and partially activates a receptor.
Antagonist
An antagonist does not itself cause a response in the postsynaptic cell. Instead, the antagonist prevents a neurotransmitter from having its effect. The antagonist does this by directly binding and blocking a postsynaptic receptor or by affecting a site other than the postsynaptic receptor, perhaps by blocking synthesis or release. Naloxone is an example of an opioid antagonist.
Placebo vs Nocebo
Placebo: pharmacologically inert substance that can elicit a significant therapeutic response
Placebo effect: expectation of a positive outcome
Nocebo effect: expectation of a negative outcome of a placebo treatment can produce harmful effects
Efficacy
the maximum effect that can be produced by a drug; the peak of the dose–response curve
Therapeutic index
a measure of a drug’s safety given as the ratio of the average lethal dose of a drug divided by the therapeutic dose (ex The LD50 is the dose that is lethal to 50 per cent of the test animal population, while the ED50 is the effective dose—the amount required to produce the desired effect in half the population). Should be big as possible.
Margin of safety
an index of a drug’s effectiveness and safety
Tolerance
a phenomenon whereby chronic use of a drug can decrease the drug’s effects, can develop rapidly or not, can be reversed.
Dose-response curve
a measure of a drug’s effectiveness as a function of the dose administered. Example: small amount of meth does same as very big amount of caffeine.
Dose
quantity of drug that is taken into the body (milligrams mg)
Dose isn’t number of pills taken, number of injections
Dosage
Dose of drug will have influence effect it has on body. Appropriate dosage depends on nature of the drug, body weight, prior experience with the drug, age, overall health
Route of Administration
the method by which a drug is taken into the body, determines how much of a drug reaches its site of action and how quickly the drug takes effect.
first-pass effect
the phenomenon by which orally administered drugs are metabolized by liver enzymes before they reach the general circulation, thus significantly reducing their bioavailability
Drug depot and plasma proteins
A drug depot is an area of the body that can accumulate and store a drug, but where no significant biological effect of the drug occurs. When a drug is stored in a depot or bound to plasma proteins, the drug is temporarily unable to reach its target site, which slows its onset of action and reduces its effect. In addition, the stored drug does not reach the liver to be metabolized, which can prolong its action.
Drugs half-life
A drug’s half-life is the time it takes for the amount of drug in the body to be reduced by 50 per cent. Drugs with a long half-life stay in the body for longer periods of time at close to their full strength
_______ refers to the method by which a drug crosses the membranes of the body and ends up in the bloodstream.
Route of administration
What is the optimal ROA for a drug that should be delivered slowly and steadily in a patient who is afraid of giving themselves an injection?
Transdermal
One of the major disadvantages of oral drug administration is that when certain drugs are metabolized by the liver, they lose much of their potency before reaching the brain. This is called the _______ effect.
first-pass
THC that is stored in an area in the body where it has no significant biological effect, such as fat, is said to be stored in a(n)
drug depot
Because many drugs bind to plasma proteins, muscles, or fats (where they remain inactive), it is possible to activate the effects of one such drug by
introducing another drug into the system that has a stronger affiliation to bind to the same site
What refers to the biochemical process of modifying a drug to facilitate excretion from the body?
Biotransformation
This organ contains hundreds of enzymes that synthesize, alter, and deactivate drugs during the metabolism process.
Liver
First vs zero order kinetics
First-order kinetics: when drug levels are high, the drug is cleared from the body more rapidly. As drug levels drop, the clearance rate is reduced.
Zero-order kinetics: the drug is cleared from the body at a constant rate, regardless of the drug concentration
Speed of drug metabolism may be influenced by genetic variations, such as having abnormally low levels of enzymes which are part of the _______ complex.
cytochrome P450
The _______ is the most important organ for elimination of drugs and their metabolites.
kidney
Drug action
specific molecular changes produced by a drug when it binds to a receptor and the physiological, psychological, and behavioural changes that occur as a result.
Ligand
A ligand is any molecule, humanmade or natural, that binds to a receptor. When a ligand comes upon a receptor into which it fits, it temporarily binds, producing a physical change in the shape of the protein, which initiates a series of intracellular events that ultimately generate an effect.
Affinity
how well a drug binds to its target
Additive, synergistic and antagonism effects
Additive effects occur when drugs taken together produce an acute effect that is equal to the sum of each drug administered separately. When two drugs are synergistic, the effects of taking them together are greater than the effects of taking either drug alone. In antagonism, one drug (such as naloxone) cancels or blocks the effects of another drug (such as heroin)
Metabolic and cellular tolerance
metabolic tolerance-
tolerance that occurs when the body speeds up the metabolism of a drug by increasing the production of certain liver enzymes. cellular tolerance-
tolerance that occurs when cells adapt to the presence of a drug by changing receptor density
Homeostasis
the tendency of the body to try to maintain equilibrium, even when faced with external changes
Downregulation
the process by which a cell decreases the number of receptors in response to an increased amount of neurotransmitter in the synapse
Your doctor prescribes a drug for your migraine episodes, stating, “This drug does not work like OTC pain relievers or even prescription pain medication. Instead it works by constricting your intracranial arteries to reduce the over-dilated blood vessels in your brain.” She is explaining the drug’s
pharmacodynamics
If you have a receptor site in your body and there exists a drug which fits exactly to that receptor, it is safe to assume that
your body must also have an endogenous form of that drug which it produces naturally
When interpreting a drug’s _______, danger is indicated by quantifying the overlap between the effective dose and the toxic dose of the drug.
therapeutic index
The _______ is the preferred method for expressing a drug’s safety for use in humans because it relies on data measuring effectiveness and lethality in the general human population.
margin of safety
Brain-derived neurotrophic factor (BDNF)
acts as a “molecular switch” in the transition from drug use to drug dependence and addiction, and serves as a key mediator in the neural effects of antidepressant therapy.
