Question | Answer |
Phases of Drug Action | Pharmaceutical phase
Pharmacokinetic phase
Pharmacodynamic phase |
Pharmaceutical Characteristics of Drugs
Physical Properties of the Drug: | Drug Composition
Tablet
Capsule
Powder
Suspension Solution
Excipients
Coatings |
Routes of Administration | 1. Enteral Routes:
Oral
Gastric
Rectal
2. Parenteral Routes:
Skin (topical)
Lungs (inhalation)
Nasal cavity
Injection sites
Subcutaneous (3-5 min)
Intramuscular (3-5 min)
Intravenous (15-30 sec)
Intraperitoneal
Intrathecal |
Rate-Limiting in Pharmaceutical Phase
Tablets: | Capsules (slower speed)
Disintegration
Powders (medium speed)
Dissolution
Suspensions & Solutions (fastest speed)
Absorption |
Pharmacokinetics | A mathematical model of drug disposition in the body |
Steady State | quantity of drug in the body remains constant (rate in = rate out) |
Half-life | the amount of time required to reduce the blood-drug concentration to one half the original value |
Therapeutic Range | Blood drug concentrations which generally have little toxicity & are highly effective |
Determinants of the
Pharmacokinetic Phase
Drug Absorption: from fastest to slowest | Inhaling
7- 10 sec Injecting
15-30 sec Snorting
3-5 min Orally
20-30 min
Transdermal
1-2 days |
Determinants of the Pharmacokinetic Phase
Drug Distribution: | Tissue Mass
Percentage of body fat
Blood volume to tissue
Drug acceptors
Tissue barrier mechanisms
--Blood-brain barrier
--Placental barrier |
Determinants of the Pharmacokinetic Phase
Drug Biotransformation: | Inactive Drug– Active Metabolite
Active Drug– Less Active Metabolite
Active Drug – Equipotent Metabolite |
Pharmaceutical Characteristics of Drugs
 Chemical Properties of the drug | Drug concentration
Molecular size
Lipid/ water solubility
Degree of ionization |
Biological Fate of Psychoactive Drugs
Psychobiological Effect (STEPS A DRUG TAKES THROUGH THE BODY) | 1. Absorption
2. Distribution
3. Accumulation at Receptors
4. Receptor Occupancy
5. Biotransformation to Inactive Metabolites 6. Redistribution
7. Elimination |
biological factors | Body weight/ size Age
Gender
Genotype
Health condition
Nutritional status
Pharmacological state Environmental setting
Psychological disposition
Personality variables
Expectations (set) about drug effects |
how does gender effect drug use | women and men have different chemicals and hormone levels that affect drugs absorption (ex: more chemicals present in men’s stomach than women’s that allow alcohol to be processed)
women have more body fat (factors into metabolization ) |
anadamide effects | Sensory experiences, controls learning, memory, analgesic |
Dopamine effects | Fine motor regulation, reinforcement, olfaction, mood, concentration, hormone control |
Serotonin effects | Emotional processing, mood, appetite, temperature control, sleep, pain processing,
hallucinations, reflex regulation |
GABA | Major inhibitory neurotransmitter in CNS, muscle relaxation |
Endorphins effects | Regulation of pain, mitigation of stress, physiological function |
Epinephrine: effects | Function as a stimulant, demands energy for body, motivation, hunger, attention span, confidence & alertness |
what are Neurotransmitters | classified as excitatory or inhibitory according to their effects on postsynaptic membranes. |
A neurotransmitter is called excitatory (ex: ACh) | if activation of the receptor causes depolarization of the membrane and promotes action potential generation. |
A neurotransmitter is called inhibitory (ex: GABA) | if the activation of the receptor causes hyperpolarization of the membrane and depresses action potential generation. |
Schedule I
abuse potential
use
medical value
ex | Abuse potential: high
Use:?
Medical value (USA): none, unsafe without proper supervision
Ex: heroin, LSD, THC, PCP |
Schedule 2
abuse potential
use
medical value
ex | Abuse potential: high
Use: may lead to severe dependence Medical value: yes
Ex: opium, , cocaine, codeine, |
Schedule 3
abuse potential
use
medical value
ex | Abuse potential: less than I & II
Use: may lead to moderate physical or high psychological dependence
Medical value: yes
Ex: Tylenol with codeine, |
Schedule 4
abuse potential
use
medical value
ex | Abuse potential: low
Use: may lead to limited physical or psychological dependence
Medical value: yes
Ex: Valium, |
Schedule 5
abuse potential
use
medical value
ex | Abuse potential: lower than IV
Use: may lead to limited physical or psychological dependence Medical use: yes
ex. cough medicine |
what part of the brain do most drugs effect | Most drugs effect the reward/pleasure center of the brain |
Nicotine | One of the 4000 active ingredients in T obacco
n The most important neurotransmitter with respect to Nicotine:
̈ Dopamine |
whats the most active ingredient in tabacco and what is its neurotransmitter | nicotine
dopamine |
Four of the most important Neurotransmitters with respect to alcohol: | Glutamate
GABA
dopamine
seratonin |
what does alcohol control in the brain | Controls reasoning and judgment
Controls mood and emotions |
Most important Neurotransmitters with respect to Cannabis: | Anandamide |
Anandamide | binds with cannabinoid receptors and activates neurons, which causes adverse effects on the mind and body |
what is the Active ingredient in Cannabis | delta-9- tetrahydrocannabinol (THC). |
Stimulants (2) | n Cocaine
n Methamphetamines |
Cocaine | Cocaine prevents the reabsorption of neurotransmitters thus increasing their concentration in the synapse and intensifying the effects |
Most important Neurotransmitters with respect to Cocaine: | ̈ Dopamine
̈ Serotonin
̈ Norepinephrine |
Increase in Dopamine, serotonin, and Norepinephrine levels in Nucleus accumbens and Amygdala do what? | the reward pathway |
Methamphetamines | Methamphetamines causes these neurotransmitters to stay in the synapse longer than Cocaine does ( Norepinephrine ̈ Epinephrine
̈ Dopamine) |
Most important Neurotransmitters with respect to Methamphetamines: | Norepinephrine ̈ Epinephrine
̈ Dopamine |
Methamphetamines does what to the brain? | will increase the concentration of Dopamine causing pleasure and in turn activating the pleasure circuit of the brain |
Hallucinogens (2) | n MDMA
n LSD
n Psilocybin |
Major neurotransmitter with respect to MDMA: | ̈ Serotonin |
Serotonin what does it do and whats it controlled by? | plays an important role in the regulation of mood, sleep, pain, emotion, appetite, and other behaviors controlled by the Limbic system |
Major neurotransmitters with respect to LSD: | Serotonin - involves in emotions and the senses
̈ Norepinephrine – a sudden release causes an over sensitization of senses |
Psilocybin | Active ingredient in a number of psychedelic mushrooms |
Major neurotransmitters with respect to Psilocybin | Serotonin - involves in emotions and the senses
̈ Norepinephrine - a sudden release causes an over sensitization of senses |
Cerebral cortex controls what | controls mood, cognition, and perception |
Environmental & developmental influences are reasons for leading a person into drug abuse what are some examples | Stress
Anger
Peer pressure Boredom |
Psychoactive Drugs: | Can cause addiction even to those not made susceptible by:
Heredity
Environment
-Excessive, frequent, prolonged use can modify neurochemistry |
Compulsive Behaviors | -Gambling, compulsive sex, eating disorders
-Dysfunctions of brain chemistry
-Unlike OCD since actions are associated with pleasure |
Addiction characterized by: | Tolerance
Tissue dependence
Withdrawal syndrome
Psychological dependence |
Addiction occurs when | the body adapts to the toxic effects of drugs
Given enough of a drug, a person will become addicted |
The Diathesis-Stress Theory of Addiction | genetics, environment, availability, behaviors (risk taking) |
Compulsion Curves | heredity, environment, & drug use
Different for every person & every substance |
Hereditary susceptibility: | Inherited brain structure
Inherited neurochemical composition |
Environmental Factors:
Can increase susceptibility to habituation, abuse, & addiction
examples of these | Childhood experiences
Friends
Nutrition
Heredity + Environment Levels of Use
Addiction Abuse Habituation Social/recreatio
nal Experimentation Abstinence
Levels of susceptibility
Susceptibility
Stress
Media/ads |
Long-term or heavy drug use: person to person | Might take those with low susceptibility 10 years or more of heavy drinking to become alcoholics.
Might take someone with high susceptibility less than a year |
Abstinence & detoxification:
(addiction/detox) | Once people have become addicted, they have changed their brain chemistry.
When they stop using, their susceptibility will drop somewhat but never to their starting point. |
someone with an ADDICTION: | Practices addiction most of
the time Continues use despite
adverse consequences
Denies there |
levels of use: | abstinence(not using)
experimentation (infrequent use, curious)
social/recreational
habituation (regular patter of use, loss some control over drug)
drug abuse: continued use despite negative consequences
addiction (compulsive use, loss of control) |
Factors Affecting Physiological Dependence | Social
Economic
Drug characteristics
Drug user characteristics |
Factors affecting actions of drugs | Drug Potency
Drug Receptors
--Agonist Drugs
--Antagonist Drugs |
Pharmacodynamic model of drug withdrawal: | Acute phase
-Physical withdrawal
Latent phase
-Cravings
-Depression
-Mood alterations |
addiction triangle | organism, drug, environment (addiction center)
Organism: personality, genetics, health
Drug: hedonic effects, withdrawal reactions, physiological
impact
Environment: legal factors, social, stress, availability |
Addictive Disease Model AKA medical model | a disease that is:
Chronic
Progressive
Relapsing
Incurable
Potentially fatal
Heredity- more important than environment Triggered by drug use & reacts biochemical &
neurological irregularities |
Addictive Disease Model
Heredity: | Passes susceptibility to alcoholism, drug addiction, & compulsive behaviors from generation to generation |
The alcoholism-associated gene (DRD2A1 allele gene) | Gene found in twice the number of severe alcoholics than social drinkers or abstainers (70% vs. 30%)
This compulsivity gene-found in people susceptible to alcoholism, addiction, & other compulsive behaviors. |
Compulsion Curves | Interplay among:
heredity, environment, & drug use
Different for every person & every substance |
Relapse: | Recovery from addiction is possible if stress is reduced and alternative coping strategies are adopted but any use will lead to rapid relapse |
How do drugs work? | Mimic or disrupt natural chemicals
Dopamine reward pathway
Pat Pathway |
Dopamine reward pathway | -Released from the amygdala even after only anticipating the drug
-After drug is used -> more dopamine is released -> do it again signal
-Stop/satiation pathway -damaged in addicts |
ADH | Alcohol Dehydrogenase
A fast ADH or a slow ALDH enzyme can cause acetaldehyde to build up in the body.
This may affect an individual’s risk level for alcholism. |
ALDH | Acetaldehyde Dehyrogenase
A fast ADH or a slow ALDH enzyme can cause acetaldehyde to build up in the body.
This may affect an individual’s risk level for alcholism. |
The major psycho-active ingredient of the marijuana plant is | delta-9-tetrahydrocannabinol (THC) |
Cannabis | Most popular illicit psychoactive drug
Major psychoactive ingredient is delta-9-tetrahydrocannabinol (THC)
Magnifies the existing personality traits of the user
Effects depend on mind-set of the user and setting |
pure food and drug act | 1906: Pure Food and Drug Act required the labeling of any cannabis in any Over-The-Counter remedies |
controlled substance act | 1970: Controlled Substance Act reported Marijuana had no potential for medical use |
The Harrison Narcotics Act | The Harrison Narcotics Act 1914 required those who dispensed "narcotics" to register with the Bureau of Internal Revenue (predecessor to the IRS), pay a tax, and keep records of the drugs they dispensed. |
Spectrum of Pharmacological Effects1 | 1. Disruption in mechanism of attention 2. Impairs short term memory
3. Altered interpretation of sensory info 4. Analgesia
5. Decrease control of motor movement 6. Immunosuppressant
7. Ptosis
8. Increased heart rate
9. Sleepiness
. Relaxation |
How THC Affects the Body | High concentrations of cannabinoid receptors in the hippocampus, cerebellum and basal ganglia.
The hippocampus is important for short-term memory. |
Inhalation:Factors Affecting Smoked Marijuana Potency: | Concentration of THC in plant
Amount Smoked
Time period for drug ingestion
Depth of inhalation |
half life of weed ( inhalation) | Half life about 30 hours |
Oral: marijuana intake | Absorption slow & incomplete
Onset of action takes 30-60 min & peaks at 2 – 3 hours
THC is about 3 times more effective when smoked versus oral |
THC Usage Acute Use: | Impairs ability to perform complex function requiring attention & mental coordination |
Effects of THC on the body
Reproductive System: | Chronic use by males:
can reduce testosterone levels & sperm count
Chronic use in females:
can reduce hormones FSH & LH
can affect menstrual cycles
Infants born of marijuana-smoking mother: display withdrawal |
Tolerance to Cannabis sativa occurs by 2 separate mechanisms: | 1. desensitization of brain cannabinoid receptors
2. rapid receptor internalization followed by agonist binding & receptor activation |
tolerance | occurs fairly rapidly, even though initially smokers become more sensitive, not less to desired effects. |
Dependence ( 3 elements) | 1. Preoccupation with acquisition of the drug
2. Compulsive use of the drug
3. Relapse to or recurrent use of the drug
(emotionally driven dependence) |
Indole Psychedelics | LSD & Psilocybin |
Catecholamine Psychedelics | Peyote (mescaline) & MDMA |
Cannabinoids: | Marijuana |
Other Psychedelics: | Ketamine & PCP |
hallucinogens general effect | Delusions
• Hallucinations
• Stimulations
• Impaired judgment • Distorted reasoning |
LSD | LSDbindstotheserotonin receptors in the brain.
• Affectstheraphenuclei, the center of serotonin activity.
– This filters the incoming sensory stimuli.
– LSDdisruptsthisprocess, leading to the surge of sensory data. |
Dr. Albert Hoffman | 1st extracted LSD in 1938
• Was used as therapy for mental illness & alcoholism
• 1st discovered Psilocybin in 1959 |
LSD
• Physical Effects: | • Rise in heart rate & blood
pressure
• Higher body temperature • Dizziness
• Dilated pupils
• Glassy eyes
• Some sweating like amphetamines |
LSD after effects | no dependece
• Flashbacks – Short term
LSD
– One feels the same as they did on the initial trip, which could be pleasant or unlikeable.
• Hallucinogen persisting perception disorder (HPPD)
long term symptoms similar to Schizophrenia |
Psilocybin & Psilocin | Activeingredientsin“magic mushrooms”
• Bindstotheserotoninreceptors in the brain
• Alsoaffectstheraphenucle |
Ketamine
(originally used?) | • Dissociativegeneral
anesthetic
• used in human & veterinary medical procedures
• SimilartoPCP |
pcp how was it originally used and what forms does it come in? | • Originally used as a general anesthetic in humans but caused hallucinations & was
discontinued
Forms:
Liquid, Crystal, Powder |
MDMA | • Releases reservoirs of serotonin in brain
• More serotonin induces feelings of happiness |
Opium | Opium - the exuded substance from the poppy Papaver Somniferum which is harvested to make opiates and opioids |
opiate | Opiate - a drug naturally extracted from opium sap; used to make morphine and codeine; bind to endogenous opiate receptors in the human body |
Opioids | Opioids - natural and semi-sythetic opium- derivatives as well as wholly synthetic opium-like compounds that also bind to the opiate receptors and have agonistic (activating) properties |
Endorphins - | Endorphins - naturally occurring internal analgesic peptides which induce morphine- like effects (antagonists of the opioid receptors) |
Most Common collegiate Opioids Abused + Relative Strengths | § Codeine: 1 unit (of strength)
§ Vicodin/Norco (Hydrocodone): 4-6x’s (codeine) § Morphine: 7-10x’s
§ Percodan/OxyContin (Oxycodone): 15-20x’s
§ Heroin: 20-30x’s |
Codeine | Commonly prescribed as an analgesic, antitussive (cough suppressant), and antidiarrheal |
Vicodin and Norcos | Opioid: semi-synthetic derivative from/of codeine (though it is far more powerful)
§ Active ingredients: Hydrocodone and acetaminophen (Tylenol) |
OxyContin and Percodan | Activeingredient:Oxycodone
§ Semi-sythetic (derived from a stimulant poison in opium called Thebaine)
§ Treatmentforsevere-to-intolerablelong-termpain
HIGHLY addicting, quick development of dependence, and EXTREMELY potent
§ Tolerance develops rapidl |
Heroin: Routes of Administration | § Injection: commonly found in the hydrochloride salt form, which can be mixed with water and injected with a syringe
§ Oral: ingestion into gastrointestinal tract
§ Insufflation (snorting): crushed and absorbed
into sinus cavity
§ Inhalation: |
most widely abused substance in the whole world | caffine |