HSS3106 Midterm

Pharmacology

Pharmacology

study of medications

Drug

substance capable of producing a biologic response

Medication

a drug given for the purpose of producing a therapeutic response

Therapeutics

branch of medicine concerned with the prevention of disease and treatment of suffering

Pharmacotherapeutics

using medications to prevent disease and treat suffering

Traditional medications

Produced by pharmaceutical manufacturer (i.e., aspirin)

Biologics

agents produced by animal cells and microorganisms eg. hormones, antibodies, vaccines

Natural Health Products

• Natural plant extracts

• Vitamins, minerals

• Dietary supplements

Prescription Drugs

Require a dispensing order (prescription) from a qualified health care professional prior to patient receiving drug

Over-the-counter (OTC) Drugs

Drugs that can be obtained by patients without consultation with a health care provider

Prescription Drugs

benefits of patient follow up, dose and frequency of drug are controlled, health care providers examine and diagnose patient prior to ordering medication, to ensure it is appropriate for the patient

OTC Drugs

benefits of being cost-effective, convenient, gives quick relief, self-treatment, has a high margin of safety, do not require authorization from health care provider

Reclassification

Prescription drugs can be changed to over-the-counter drugs by manufacturer or mandated by FDA, needs a high safety margin

What is not a drug which means that it is not tested by the FDA, does not go through a regulatory process, can cause side effects and interact with medications ?

Herbal and dietary supplements

Who sets the standard of the Canadian Drug Regulations ?

Food and Drug Act and Regulations as all drugs must go through it to be approved

Canadian Drug Regulations

Created to protect the public from drug misuse and to provide mechanism for quality assurance for safety and efficacy

Health Products and Food Branch (HPF B) of Health Canada

responsible for ensuring the safety and quality of drugs, biologics and natural health products

Therapeutic Products Directorate (TPD)

Federal authority that regulates pharmaceutical drugs, TPD approval required for drug to be marketed in Canada

Biologics and Genetic Therapies Directorate

Parallel branch to TPD that regulates biologics and radiopharmaceuticals such as radioisotopes and covid vaccines

Natural and Non-prescription health Products Directorate

parallel branch to TPD that regulates natural health products

Step 1 of Canadian Drug Approval Process

preclinical trials using cultured cells, living tissues and small animal models

Step 2 of Canadian Drug Approval Process

Clinical Trial Application and testing

• Phase I – Healthy subjects

  o Evaluate safety of drug and possible

  adverse effects

• Phase II – Small group of patients with target

  condition

• Phase III – Large group of patients with target

  condition

Step 3 of Canadian Drug Approval Process

manufacturer completes New Drug Submission (NDS) to Health Canada

• Outlines test data obtained from clinical trials, indication, adverse effects, production and packaging

Step 4 of Canadian Drug Approval Process

committee of drug experts reviews NDS to identify benefits and risks

Step 5 of Canadian Drug Approval Process

Health Canada shares information about drug with health care providers and consumers

Step 6 of Canadian Drug Approval Process

if approved, Health Canada issues a Drug Information Number (DIN) and a Notice of Compliance to manufacturer

• Both required for marketing drug

Step 7 of Canadian Drug Approval Process

Health Canada continues to evaluate drug safety and efficacy through quality assurance processes

Thalidomide Scandal

Condition called focal milia where children were born with their limbs not fully developed from being in embryo, don’t get angiogenesis which stops development of their limbs, this occurred when they used to treat pregnant women with morning sickness in the 60s with thalidomide pills

Therapeutic classification

Describes the condition for which a medication is being given (i.e.; antihypertensive), physiological change by the drug (indication)

Pharmacologic classification

Describes the mechanism by which the therapeutic effect is achieved (ie. Beta blockers, diuretics, ACE inhibitors), mechanism of action on the molecular level

Indication

condition or circumstance for which drug has been approved, a particular drug may have multiple indications

Mechanism of Action

Means by which drug carries out a therapeutic effect i,e.; a diuretic (pharmacologic class) reduces blood pressure (therapeutic class) by reducing blood volume (mechanism)

Prototype drug

a representative drug from a class that is used as a point of comparison for related versions of that drug

Generic

name adopted by regulatory agencies to describe active ingredient of a drug (preferred name), usually less expensive than brand name

Trade

proprietary name used by the company that produces a drug

bioavailability

the amount of drug that reaches systemic circulation and that can interact with target tissues

Schedule I Drugs

• Require a prescription for sale.

• Provided to the public by a pharmacist following a diagnosis and professional intervention of a practitioner.

• The sale of schedule I drugs is controlled in a regulated environment as defined by provincial pharmacy legislation

• eg. fentanyl for cancer

Schedule II Drugs

• Requires professional intervention from the pharmacist at the point of sale and possibly referral to a practitioner.

• Prescription is not required.

• These drugs, however, are available only from a pharmacist

• Still behind the counter eg. vaccines

Schedule III Drugs

• May present risks to certain populations in self-selection

• May present risks to certain populations in self-selection.

• These drugs are sold from the self-selection area of the pharmacy

• eg. OTC

Unscheduled Drugs

• Sold without professional supervision.

• Adequate information is available for the patient to make a safe and effective choice

• These drugs are not included in Schedules I, II or III and may be sold from any retail outlet

• eg. herbal supplements

Controlled Substances

Drugs that affect the central nervous system that have high potential for abuse and addiction and must be listed in Controlled Drugs and Substances Act (CDSA)

Psychological dependence

craving for a particular drug

Physical dependence

• nervous system changes in response to presence of drug

• Patient experiences withdrawal symptoms if drug is discontinued

Hallucinogens

Affects the user’s perceptions, thinking, self-awareness, and emotions

Effects of an overdose on hallucinogens

• high heart rate & blood pressure

• panic attacks, anxiety, or psychosis

Examples of Hallucinogens

• MDMA/ecstasy (high heart rate & blood pressure, muscle cramps, loss of consciousness, panic attacks), Mescaline (hallucinations, euphoria, dizziness, vomiting, anxiety), LSD (dilated pupils, increased heart rate and blood pressure, dry mouth, hallucinations), PCP (increased HR & BP, convulsions, sweating, numbness, death from heart failure)

Narcotics

a drug that is meant to sedate or induce sleep but in less potent forms, used as a pain reliever because of its ability to relax muscles & provide relief as a sedative

Examples of Narcotics

Opium (Difficulty breathing, low blood pressure (BP), weakness, dizziness, cold clammy skin, small pupils), Heroin/Codeine/Morphine (Difficulty breathing, low BP, coma, spasms of the stomach or intestines, blue fingernails and lips, death), Methadone (Difficulty breathing, drowsiness, coma, low BP, blue fingernails and lips), Oxycodone (Slow difficult breathing, seizures, dizziness, weakness, coma )

Fentanyl

a narcotic often added to other illegal drugs without people knowing and is 50-100 times more potent than heroine/oxycodone/morphine but is also a prescription drug for cancer patients in severe pain, 2 mg of fentanyl is a lethal dose in most people

Stimulants

• Cause increases feelings of energy and alertness, suppresses appetite and afterwards, depression often results.

• Overdose affects include high blood pressure, agitation, confusion, seizures

Examples of Stimulants

Cocaine/Crack Cocaine (Dangerous rise in body temperature, sweating, tremors, irregular heartbeats, stroke), Amphetamines/Speed (High blood pressure (BP), rapid heart rate (HR), agitation, irregular heartbeats, stroke, death), Methamphetamines (Dangerous rise in body temperature, profuse sweating, confusion, rapid breathing, bleeding in the brain, death), all of them experience euphoria

Cocaine

• Powerful Central Nervous System (CNS) stimulant.

• Effects last 15 minutes to an hour, depending on method of ingestion.

• Increases alertness, feelings of well-being & euphoria, energy & motor activity, feelings of competence & sexuality.

• Athletic performance may be enhanced (attention & endurance)

Effects of Cocaine

dilated pupils, nosebleeds, elevated BP, hallucinations, anorexia, seizures, tachycardia, sniffing

Effects of Methamphetamine

Acne appears or worsens, Obsessive skin-picking, the result of a common sensory hallucination of bugs crawling beneath the skin, suppresses appetite, body begins consuming muscle tissue and facial fat, tooth enamel is dissolved by the harsh chemical of the drug

Methamphetamine

Highly addictive stimulant drug, affects the central nervous system (CNS) and they are produced in illegal laboratories

Anabolic steroids

• A chemical structure similar to testosterone.

• Promote cell and tissue growth increasing bone mass and body muscle.

• Popular with weightlifters, bodybuilders, and other athletes

Effects of anabolic steroid use

Headaches, Baldness, Strokes & blood clots, High BP & heart disease, Impotence, Reduced sperm count, Aggressive behavior, Mood swings, Shrinkage of the testicles, Liver damage that causes cancer, severe acne

Gynecomastia

development of breasts in anabolic steroid users

Testicular Atrophy

shrinking of testes in anabolic steroid users

Cardiac Hypertrophy

abnormal enlargement, or thickening, of the heart muscle involving the left ventricle as big hearts do not function well, diminishing performance and increasing the risk for sudden death

CNS depressants

Substances that slow down normal brain function by increasing GABA activity (a NT), sometimes called sedatives or tranquilizers so it helps to relieve anxiety & produces sleep

2 commonly prescribed CNS depressants

Barbiturates (prescribed for the treatment of anxiety or tension, or for people with sleep disorders, causes mood changes and excessive sleep) and Benzodiazepines (Prescribed for patients with more serious anxiety and panic attacks)

Alcohol

a drink that contains a substantial amount of ethanol

Effects of Alcohol

depression of inhibitory control, vasodilation, decreased memory & concentration, poor judgment, decreased reflexes

Effects of chronic consumption of alcohol

• Lost productivity, impaired performance, cost to society

• Liver cirrhosis and liver cancer

• Pancreatitis (inflammation of the pancreas) & pancreatic cancer

Why is pancreatic cancer hard to detect ?

• No noticeable S&S in the early stages of the cancer.

• S&S of pancreatic cancer, when present, are like the S&S of many other illnesses.

• Pancreas is deep hidden behind other GI organs.

Liver cirrhosis

• Advanced liver disease results in loss of liver function.

• Characterized by replacement of liver tissue by fibrosis (scar tissue) and regenerative nodules (lumps that occur due to attempted repair of damaged tissue).

• Commonly caused by alcoholism, hepatitis B and hepatitis C, fatty liver diseases

Most common cancer in adults

Liver cancer

Effects of alcohol during pregnancy

• Miscarriage

• Stillbirth

• Prematurity

• Sudden infant death syndrome (SIDS)

• Fetal alcohol spectrum disorders (FASDs)

Fetal alcohol spectrum disorder

A condition that causes development delays such as speech & hearing impairment, learning & attention deficits, cognitive delays in a child due to the mother drinking alcohol while pregnant

Pharmacokinetics

What the body does to the drug, changing in concentration of drug through physiologic processes involving ADME

Pharmacodynamics

what the drug does to the body, physiological & biochemical process of mechanism of action of drugs that involves dose-response relationship, receptor binding/affinity, and potency & efficacy

What does the A in ADME stand for ?

Absorption

What does the D in ADME stand for ?

Distribution

What does the M in ADME stand for ?

Metabolism

What does the E in ADME stand for ?

Excretion

What does absorption do ?

Movement of drug from site of administration to circulation

What does distribution do ?

Transportation of drug throughout body to target tissue

What does metabolism do ?

How the drug is altered by body

What does excretion do ?

How the drug is removed from body

What organs are used for absorption ?

Mainly the small intestine but also the stomach due to being affected by HCl

What organs are used for distribution ?

Blood stream in circulatory system

What organs are used for metabolism ?

Liver

What organs are used for excretion ?

Large intestine and kidneys

Bound drug

Drug that binds to plasma proteins in the bloodstream to make a drug-protein complex which are too large to cross membranes

Free drug

Drugs that are left over in the body that aren’t bound to the bloodstream

3 properties of drugs that affect diffusion

Concentration gradient (dosage of the drug), size of drug molecule (smaller molecules absorbed faster) and lipid solubility (structure of molecule, ionization of molecule which is influenced by pH, lipophilic drugs cross membranes more easily than hydrophilic drugs)

Simple Diffusion

Movement of a chemical from an area of higher concentration to an area of lower concentration, does not require energy, smaller molecules that are lipophilic like O2, CO2, heroine, caffeine, nicotine

Facilitated Diffusion

Diffusion requires a transport protein like ion channels, does not require energy but needs a concertation gradient to be maintained from higher concertation to lower concentration, used for glucose, amino acids, and peptides

Osmosis

Diffusion of water down its concentration gradient from higher water concentration (lower solute concentration) to lower water concentration (higher solute concentration), does not require energy

Active Transport

Diffusion requires energy and follows concentration gradient from lower solute concentration to higher solute concentration

Bioavailability

eg. getting pain killer, anti histamine all in one pill

Route of Administration

Increasing the dose increases rate of absorption due to increased concentration gradient

Enteral

Uses oral, sublingual, rectal as routes of administration

Parenteral

Uses intramuscular injection, subcutaneous injection, intravenous injection as routes of administration

Topical

Uses epidermic, irrigation as routes of administration

Inhalation

Uses vaporization, gas inhalation, nebulization as routes of administration

Slowest route of administration

Enteral

Fastest route of administration

Parenteral

Localized route of administration

Topical