NR 668 Week 4 Psychopharmacology
1. Pharmacodynamics: How the drug effects the body
-therapeutic vs. side effects
• Is it stimulating?
• Is it depressing?
• Does it block something?
-Onset of action
• Route, Dosage
-Duration of action
• Redistribution rate, metabolism rate and excretion rate
-Mechanism of action
• Drugs simply speed up or slow down what is already occurring in the body
-Eflcacy
• (Intrinsic activity) After binding, the drugs capacity to cause an effect
-Potency
• The amount of a drug needed to produce a given effect
2. efficacy examples: -Agonist (Eflcacy = 100)
-Partial Agonist (Eflcacy = > 0 < 100)
-Antagonist (Eflcacy = 0.0)
-Inverse Agonist (Eflcacy = < 0)
,3. Agonist:: Compounds which give maximal response after receptor occupation and activation.
-Example: Oxycodone
4. Partial Agonists:: Compounds which activate the receptor but not at the maximal response.
-Example Buprenorphine (Suboxone) or Buspirone
5. Antagonist:: Blocks the action of an agonist.
-Example: Neuroleptics, Naloxone
6. Inverse Agonist:: Binds to receptor and has the opposite action of an agonist and below baselinesignal
transduction
7. Pharmacokinetics: How the body effects the drug
-Absorption, distribution, metabolism and elimination (ADME)
-Metabolizing the drug via CYP450 through the gut & liver
8. Bioavailability: Absorption: Drugs cross a barrier.
-Involves bioavailability or Quantity of drug reaching circulation/quantityof the drug administered.
,• Our own barriers such as skin and mucous membranes as well as food, molecular weight, chemical, biological barriers,
etc. reduce how much drug is actually absorbed and available. IV route has 100% bioavailability. All other routes <100%
9. First pass metabolism: -reduces the concentration of a drug
• travels through digestive system & entering the liver.
• reducing the bioavailability of the drug
10. rate is reduced by:: -Route (IV, PO, Rectum, etc.)
-Dosage (Concentration)
-Lipid Solubility
11. Drugs that cross the BBB are : fat soluble
12. Vd: Volume of distribution = : amount of drug/concentration
• large Volume of distribution may indicate the drug distributes extensively into the body
• Vd is a theoretical fluid volume necessary to contain the total amount of a drug at the same concentration observed
in the plasma
13. A patient who is in renal failure would have a increased or decreased Vd?: -
Increased because of fluid retention
14. plasma protein binding: -cannot leave the circulation easily
-Free (unbound) crosses membranes
, -Two drugs that are both highly protein bound will compete with each other
• The unbound fraction goes through metabolism and is responsible for the pharmacologic effects
-rapid weight loss may result in drugs being released from fat cells
15. Drugs that are highly protein bound and have a narrow therapeutic index
can be dangerous because:: margin of error between therapeutic and toxic is narrow
16. Metabolism: -Mostly in the liver
-Biotransformation or change it to inactive form or make it more water soluble to facilitate excretion
• transformed substance is called the metabolite.
17. The rate of metabolism is affected by:: -age, liver & drug tolerance
• Body may produce more enzymes & the liver becomes faster at breaking that particular drug down
18. half life: this is the time it takes the peak level to fall by ½
19. Steady state of a drug:: -When the rate of drug administration & elimination are equal
-can be achieved in 4 - 5 half lives
20. Phase I reactions:: Transforms drug, CYP450 Oxidases. Make it available for the body to use
1. Pharmacodynamics: How the drug effects the body
-therapeutic vs. side effects
• Is it stimulating?
• Is it depressing?
• Does it block something?
-Onset of action
• Route, Dosage
-Duration of action
• Redistribution rate, metabolism rate and excretion rate
-Mechanism of action
• Drugs simply speed up or slow down what is already occurring in the body
-Eflcacy
• (Intrinsic activity) After binding, the drugs capacity to cause an effect
-Potency
• The amount of a drug needed to produce a given effect
2. efficacy examples: -Agonist (Eflcacy = 100)
-Partial Agonist (Eflcacy = > 0 < 100)
-Antagonist (Eflcacy = 0.0)
-Inverse Agonist (Eflcacy = < 0)
,3. Agonist:: Compounds which give maximal response after receptor occupation and activation.
-Example: Oxycodone
4. Partial Agonists:: Compounds which activate the receptor but not at the maximal response.
-Example Buprenorphine (Suboxone) or Buspirone
5. Antagonist:: Blocks the action of an agonist.
-Example: Neuroleptics, Naloxone
6. Inverse Agonist:: Binds to receptor and has the opposite action of an agonist and below baselinesignal
transduction
7. Pharmacokinetics: How the body effects the drug
-Absorption, distribution, metabolism and elimination (ADME)
-Metabolizing the drug via CYP450 through the gut & liver
8. Bioavailability: Absorption: Drugs cross a barrier.
-Involves bioavailability or Quantity of drug reaching circulation/quantityof the drug administered.
,• Our own barriers such as skin and mucous membranes as well as food, molecular weight, chemical, biological barriers,
etc. reduce how much drug is actually absorbed and available. IV route has 100% bioavailability. All other routes <100%
9. First pass metabolism: -reduces the concentration of a drug
• travels through digestive system & entering the liver.
• reducing the bioavailability of the drug
10. rate is reduced by:: -Route (IV, PO, Rectum, etc.)
-Dosage (Concentration)
-Lipid Solubility
11. Drugs that cross the BBB are : fat soluble
12. Vd: Volume of distribution = : amount of drug/concentration
• large Volume of distribution may indicate the drug distributes extensively into the body
• Vd is a theoretical fluid volume necessary to contain the total amount of a drug at the same concentration observed
in the plasma
13. A patient who is in renal failure would have a increased or decreased Vd?: -
Increased because of fluid retention
14. plasma protein binding: -cannot leave the circulation easily
-Free (unbound) crosses membranes
, -Two drugs that are both highly protein bound will compete with each other
• The unbound fraction goes through metabolism and is responsible for the pharmacologic effects
-rapid weight loss may result in drugs being released from fat cells
15. Drugs that are highly protein bound and have a narrow therapeutic index
can be dangerous because:: margin of error between therapeutic and toxic is narrow
16. Metabolism: -Mostly in the liver
-Biotransformation or change it to inactive form or make it more water soluble to facilitate excretion
• transformed substance is called the metabolite.
17. The rate of metabolism is affected by:: -age, liver & drug tolerance
• Body may produce more enzymes & the liver becomes faster at breaking that particular drug down
18. half life: this is the time it takes the peak level to fall by ½
19. Steady state of a drug:: -When the rate of drug administration & elimination are equal
-can be achieved in 4 - 5 half lives
20. Phase I reactions:: Transforms drug, CYP450 Oxidases. Make it available for the body to use
