PSYCH 265 1st EditionExam # 1 Study Guide Lectures: 1 – 9CHAPTER 4 1. Describe the difference between pharmacokinetics and pharmacodynamics. - Pharmacodynamicso What the drug does to the bodyo Study of drug action at biochemical level Mechanism of action of drug- Pharmacokineticso What body does to the drug o Study of how drugs enter the body, reach their site of action, and are eliminated from the body2. Name and describe the various routes of drug administration, and compare them in terms of onset/duration of drug effect. - Drug administrationo Process by which drug enters body Enternal-digestive tract Parenteral-route other than digestive tracto Oral Safest, food in stomach diminishes amount absorbed, reduced drug effect by stomach acids breaking down some drugso Subcutaneous  Easiest of 3 injection routes to use, faster than oral but slower than intramuscular & intravenous o Intramuscular  Deeper penetration of injection than subcutaneous but faster absorptiono Intravenous Considered fastest absorption rate, doses adjusted to persons response b/c immediate drug effects, better than other 2 b/c blood vessel walls insensitive & blood dilutes drugo Inhalation  Absorption is effective & most rapid for some drugso Intranasal  Fat & water soluble drug, absorption is rapid/effective o Sublingual  May be used in pill form, faster & more efficient absorption than oral o Transdermal Not used for many drugs b/c skin is impenetrable barrier to many chemicals, absorption is enhanced @ sites w/ greater cutaneous blood flow3. Explain how plasma protein binding and the blood-brain barrier influence drug distribution. - Plasma protein bindingo Distribution of drugs may be affected by degree to which drug binds to proteins in blood plasma  Drugs bound to plasma protein=unavailable for acting receptors  Drugs minimally bound =penetrate tissue better than highly bound BUT excreted faster Drugs highly bound=differ from minimally in terms of penetration & half life- Blood brain barrier o Drug molecules cross BBB by transmembrane BBB Best with small drug molecules that are highly lipid soluble o Large drug molecules don’t cross easilyo Ability of drug molecules that are ionized to cross BBB=impaired 4. Describe the different steps in pharmacokinetics.- Drug administrationo Drug enters body by either enteral or parenteral - Drug absorptiono Drug enters fluids of distribution of body (blood, plasma, serum, lympth ect.)- Drug distribution o Drug moves from one locus in body to another including site of action (affected by plasma protein binding & BBB)- Drug metabolism o Biochemical modification of drug by bodyo Can be inactivated/activated by body (influenced by first pass effect & enzyme induction/inhibition)- Drug excretion o Elimination of drug by body by either unchanged or as metabolite 5. Discuss how drug metabolism can be influenced by the first pass effect and enzyme induction/inhibition. - First pass effecto Drug dose absorbed by digestive tract first delivered to by liver by portal vein o Part of drug can be metabolized in liver before it reaches systemic circulation (oral bioavailability of drug reduced)- Enzyme inductiono Drug induced acceleration of metabolism by increasing production of liver enzyme o Decrease pharmalogical action of substrate enzyme- Enzyme inhibition o Blockade of enzyme by drug which may/may not be substrate o Increases concentrations of parent drug-exaggerates/prolongs effects o Prodrug inhibition may decrease response6. Define bioavailability. - Portion of the original drug dose that reaches its site of action or that reaches a fluid in the body that gives it access to its site of action.. 7. Explain the use of dose-response curves in pharmacology.a. Draw dose-effect curves for two drugs such that Drug X is (a) less potent or (b) less efficacious than Drug Y. Make sure you can estimate ED50 from a dose-effect curve. b. Draw dose-effect curves for the interaction between an agonist and (a) a competitive antagonist and (b) a noncompetitive antagonist. 0.1 1 10 100 1000 10000020406080100DOSERESPONSEc. Draw dose-effect curves for Drug X at time 1 (1st use) and time 2 (50th use), assuming that tolerance (or sensitization) develops from the 1st to the 50th use. 10 10 0 10 00 10 00 0DOSERESPONSE0.1 1 10 100 1000 10000020406080100DOSEDOSE8. Describe the three mechanisms by which we become tolerant to drugs: metabolic (dispositional), pharmacological (functional), and behavioral (learned) tolerance. - Pharmacological (functional) tolerance-decreased behavioral effects of drug as result of regular use - Metabolic (dispositional) tolerance- increase in rate of metabolizing a drug as a result of its regular use- Behavioral (learned) tolerance- adjustment of behavior through experience in using a drug to compensate for its intoxicating effectsCHAPTER 5 1. Identify some of the factors that might affect a patient’s responsiveness to a drug. - Initial sensitivity- Gender- Weight- Age - Personality 2. Describe a normal distribution of variability in responsiveness to a drug. - Bellcurve graph - Normal-middle & peak of graph - More sensitive- as you go further down on right tail end- Less sensitive- as you go further down on left tail end3. Differentiate between pharmacogenomics and pharmacogenetics. - Pharmacogenomicso Analysis of entire genomes across group of individuals, to identify the genetic factors influencing responses to a drug- Pharamacogenetics o Study of an individual’s genetic make-up in order to predict responses to a drug & guide prescription 4. Explain the fast- and slow-acetylator example of pharmacokinetic polymorphism.- Antituberculosis drug “isoniazid” is metabolized by acetylation by the enzyme liver N-acetyl-transferase- Rate of acetylation is genetically determined o 50% Caucasian/African Americans are slow acetylators o Eskimos / Asians are fast acetylators- Defect in slow is synthesis of less n-acetyltrasnferase enzyme (slow lead to higher blood levels of drug then increases in toxic reactions)5. Explain the malignant hyperthermia example of pharmacodynamics polymorphism. - When genetically susceptible subjects are general anesthetic, malignant hyperthermia may develop. Subjects develop breakdown of skeletal muscle fibers, skeletal muscle rigidity, hyperthermia, tachycardia and acid-base imbalance. 6. Explain what is meant by