Lecture 13 Flashcards by Nadia Macluskie

What is a drug?

Any substance, other than a normal constituent of the body or one that is required for normal bodily function that, when applied to or introduced into a living organism, has the effect of altering bodily function(s)

How well did you know this?

Not at all

Perfectly

What is pharmacokinetics?

Study of the time course of a drug and its metabolites in the body after administration by any route

How well did you know this?

Not at all

Perfectly

What are the types of administration does pharmacokinetics study? (4)

Absorption
Distribution
Metabolism (Biotransformation)
Excretion

How well did you know this?

Not at all

Perfectly

What are the absorption routes of administration? (7)

Oral
Sublingual/buccal
Inhaled
Topical
Vaginal, rectal
Transdermal
Injection (IV, IM, SC, IA)

How well did you know this?

Not at all

Perfectly

What are the absorption drug factors? (5)

Formation
Solubility
Particle size
pH
Drug Ionization

How well did you know this?

Not at all

Perfectly

What are the absorption host factors? (6)

Motility of gut
Food in stomach
Vomiting/diarrhea
Circulation to the site of administration
Surface area at the site of admin
Degree of first-pass metabolism

How well did you know this?

Not at all

Perfectly

What is bioavailability?

Fraction of the dose administered that reaches the systemic circulation in an unchanged state

“First pass effect”

How well did you know this?

Not at all

Perfectly

What are the 5 steps of the first pass effect?

Drug is taken orally
Drug enters GI tract
Active drug is absorbed from stomach and small intestines
High blood concentration of drug is in hepatic portal vein
Low blood levels after passing through liver

How well did you know this?

Not at all

Perfectly

What are the 5 ways of drug distribution?

Plasma
Interstitial fluids
Intracellular fluids
Transcellular fluids
Fat

How well did you know this?

Not at all

Perfectly

What are the 2 categories of factors affecting drug distribution?

Mechanical and biochemical

How well did you know this?

Not at all

Perfectly

What are the 2 types of mechanical factors drug distribution?

Blood flow
Barriers (BBB, placenta)

How well did you know this?

Not at all

Perfectly

What are the 4 types of biochemical factors affecting distribution?

Lipid solubility
Binding to plasma proteins
Accumulation in tissues
pH

How well did you know this?

Not at all

Perfectly

What are 3 characteristics of drug metabolism (biotransformation)?

Conversion by enzymes to be more polar

Occurs in the smooth ER of cells in the liver (also in kidneys, GI tract, lung, plasma)

Consists of phase 1 and phase 2 reactions

How well did you know this?

Not at all

Perfectly

What can happen to drugs during metabolism? (4)

Activated
Changed to another active metabolite
Changed to a toxic metabolite
Inactivated

How well did you know this?

Not at all

Perfectly

What are the steps of Phase 1 metabolism?

Conversion to polar metabolite:
Oxidation, reduction, hydrolysis

How well did you know this?

Not at all

Perfectly

What happens during Phase 2 (conjugation) of drug metbolism?

Coupling of drug (or its polar metabolite) with an endogenous substance

How well did you know this?

Not at all

Perfectly

What are the 3 types of factors affecting drug metabolism?

Genetic
Enviromental
Physiological

How well did you know this?

Not at all

Perfectly

What are the 4 locations of drug elimination?

Kidneys
GI tract
Exhalation
Saliva

How well did you know this?

Not at all

Perfectly

What are the 2 main points of elimination kinetics?

Half life
1st order kinetics -> 5 half-lives to reach steady state

How well did you know this?

Not at all

Perfectly

What is pharmacodynamics?

Physiological effects of drug on the body

How well did you know this?

Not at all

Perfectly

What are the 2 forms of pharmacodynamics?

Activation or blockage of cellular receptors

Signal messaging

How well did you know this?

Not at all

Perfectly

What is an agonists drug effect?

Full or partial

How well did you know this?

Not at all

Perfectly

What are types of antagonistic drug effects?

Chemical
Functional
Competitive
Non-competitive

How well did you know this?

Not at all

Perfectly

What is the lower limit therapeutic window?

Concentration that produces half the greatest possible effect

How well did you know this?

Not at all

Perfectly

What is the upper limit therapeutic window?

No more than 5-105 of patients experience a harmful side effect

What is an effective dose?

Dose that gives the required response in 50% of subjects

What is a toxic dose?

Dose that produces harmful side effects in 50% of subjects

What is the therapeutic index?

Reflects margin of safety

What is overdose toxicity?

Taking a drug above its therapeutic range

What is side effects/sensitivities?

Diarrhea from antibiotics, sedation from anti-histamines

What is an allergic reactions?

Drugs acts as an allergen/antigen and cause an immune response

What are drug interactions?

Naloxone (competitive inhibitor), inducing or inhibiting liver enzymes

3 characteristics of alcohol absorption

Occurs in GI tract by simple diffusion 70-80% in duodenum and jejunum Delayed if food in stomach

What are 3 characteristics of alcohol distribution?

Areas with high blood flow rapidly reach equilibrium (brain, heart, lungs, liver) 4% into fatty tissues Volume of distribution less for women than for men (lean body mass)

What are the 5 steps of alcohol metabolism?

Metabolized in the liver (first pass effect) Alcohol dehydrogenase (ADH) Oxidation occurs in mitochondria Aldehyde dehydrogenase (ALDH) Acetate released to blood oxidized to CO2

How does alcohol dehydrogenase vary genetically?

Can operate 5x normal Acetaldehyde accumulates resulting in vasodilation 85% Asian populations, 5-10% English, 20% Swiss

What does an aldehyde dehydrogenase-2 deficiency cause?

Increases acetaldehyde 50% Asian populations

How is alcohol principally eliminated?

Co2 and H2O

What are the % of types of alcohol elimination?

Urine <1 Lungs 1-3 Liver oxidation 90-95

What are 3 things alcohol does in the body?

Stimulant in small doses, CNS depressant at higher Diuretic Toxic effects on muscle, heart, brain, liver

What is the effect of 50-100 mg/dl of alcohol?

Incoordination

What is the effect of 150-200 mg/dl of alcohol?

Decreased reaction time

What is the effect of 200-300 mg/dl of alcohol?

Nausea/vomit/ataxia

What is the effect of >400 mg/dl of alcohol?

Coma/respiratory failure/death

What are the effects and ceiling dose of acetaminophen?

Analgesic and anti-pyretic 1000mg per dose

What are the pharmacokinetics of acetaminophen? (6)

High absorption in small intestine Metabolism in lover Time to peak: 10-60 mins Half life: 2-3 hrs Elimination through urine Overdose: depletes liver of glutathione

3 Points of nonsteroidal anti-inflammatory drugs?

Salicylates and related compounds Anti-inflammatory, antipyretic, anti-platelet and analgesic Act by inhibiting cyclooxygenase

Pharmacokinetics of NSAIDS

Absorbed rapidly from the stomach and upper SI Distribution throughout most body tissues Metabolized in liver Excreted through urine

What are the side effects of NSAIDs?

Stomach: nausea, pain, gastritis, ulcer/bleeding Kidneys: hypertension, fluid retention, renal failure Platelets: dysfunction Vessels: vasoconstriction

What are the 3 NSAIDs implications for injury?

Inhibit protein synthesis and muscle repair Inhibit tenocyte proliferation and collagen formation Impair bone healing

What are the 3 types of topical NSAIDS and what do they do?

Diclofenac, idomethacin, ketoprofen Avoid systemic effects

What are the 2 types of steroids in sports?

Anabolic and glucocorticoids/corticosteroids/cortisone

What are the indications for cortisone injections?

Bursitis, tenosynovitis, osteoarthritis

What are the contraindications for cortisone injections?

Infection, prosthetic joint, fracture

How are opioids administered?

Oral, IM, IV, epidural, intrathecal, transdermal, intranasal

What are the medical uses of opioids? (6)

Pain relief Sedation Anesthesia Cough Diarrhea Dyspnea

What are the side effects of opioids?

Nausea, dizziness, constipation, sedation, confusion High risk of dependency Overdose

What are 4 characteristics of cannabinoids?

Abruption (oral = slower onset) Distribution extensively into fatty tissues (detected 33 days) Metabolized in liver Elimination mainly through feces

What are the indications of cannabinoids?

Chemotherapy-induced N/V Spasticity Neuropathic/cancer pain Seizures Wasting syndromes (HIV/AIDS, cancer)

What are the chronic adverse effects of cannabinoids?

Anxiety, depression, psychosis/schizophrenia, cognitive impairment, lung disease, carcinogenicity

Pharmacokinetics take home point?

How body affects drug

Pharmacodynamics take home point?

How drug affects body

Tylenol take home point?

Pain and fever

NSAIDs take home point?

Pain, fever, anti-inflammatory

Cortisone take home point?

Pain, anti-inflammatory

Opioids take home point?

Limited use unless acute severe pain

Cannabinoids take home point?

Use in chronic pain

Lecture 13 Flashcards

(67 cards)