Introduction/Concepts

Question 1

Prototypes

Answer 1

• individual drugs that represent an entire group of drugs
• Most often the first drug developed but not always
• IS the standard to which newer drugs are compared
• some prototypes are replaced overtimes
• not all classes have prototypes

Ex:
morphine is a prototype for opioid analgesics
penicillin is a prototype for anti-bacterials

Question 2

Drug Law: Pure Food and Drug Act

Answer 2

Official standards and requirements of accurate labeling of drug products

Question 3

Drug Law: Durham-Humphrey Amendment

Answer 3

Desginated drugs have to be prescribed by a physician and dispensed by a pharmacist

Question 4

Drug Law: Comprehensive Drug Abuse Prevention and Control Act, Title II, Controlled Substances Act, Categories of controlled substances

Answer 4

Regulates the distribution of narcotics, categorizes it by its usefulness and its potential for abuse

Question 5

Drug Law: Orphan Drug Act

Answer 5

Manufacturers get decreased taxes and competition for those who produce drugs to treat disorders that affect very few people

Question 6

Categories of Controlled Substances: Schedule I

Answer 6

Not approved for medical use

- heroine, LSD, ecstacy, and marijuana (depends on state law)

Question 7

Categories of Controlled Substances: Schedule II

Answer 7

High abuse potential

- codeine, morphine, oxycodone, hydrocodone, barbituates

Question 8

Categories of Controlled Substances: Schedule III

Answer 8

Less abuse but high potential for dependence

- anabolic steroids

Question 9

Categories of Controlled Substances: Schedule IV

Answer 9

Some potential for abuse

- diazepam, valium, lorazepam, ambien

Question 10

Categories of Controlled Substances: Schedule V

Answer 10

Contain moderate amount of controlled substances

- cough medicine with codeine or hydrocodone

Question 11

FDA Pregnancy Categories

Answer 11

A - no fetal risk
B - animal studies show no risk
C - a potential risk, drugs may be used
D - Evidence of fetal risk, but potential benefit to mother may be acceptable
X - demonstrated fetal risk outweighs any benefit

Question 12

Drug approval process

Answer 12

• Overseen by the FDA for safety and effectiveness
• Starts with animal studies
• Next step is human studies

Question 13

Human Studies: Phase I

Answer 13

few doses are given to a certain number of healthy people to determine safe dosages, route of administration, absorption, metabolism, excretion and toxicity

Question 14

Human Studies: Phase II

Answer 14

few subjects with target disease being studied given doses – responses are compared to the healthy subjects

Question 15

Human Studies: Phase III

Answer 15

drug is given to a larger, more representative group of subjects – double blind, placebo controlled study.

Question 16

Human Studies: Phase IV

Answer 16

allows the drug to be marketed for general use (in larger amounts) and allows the manufacturer to monitor and report the drug effects.
- this is where the big adverse effects can be found.

Question 17

Sources of Drug Information

Answer 17

• American Hospital Formulary Service and Drug Facts and Comparisons - Used by pharmacists
• PDR - big book - compilation of packet inserts
• Pharmacy
• Drug handbooks
• FDA

Question 18

Pharmacokinetics

Answer 18

Actual movement of drug through the body and what the body does with the drug

Question 19

Absorption

Answer 19

• From the time the drug enters the body to the time it enters the bloodstream to be circulated
• Things that effect absorption: dosage of drug, form, route of administration, blood flow to the area, GI function and presence of food.
• Parenteral (IV, SubCut, IM)
• Enteral: (po, sl) - po is slowest route
• Topical: (transdermal, inhalation)

Question 20

Distribution

Answer 20

• the transport of drug in the bloodstream within the body
• drugs are carried by blood and tissue fluids to the site.
• Depends on adequate circulation: goes faster to organs with big blood supply (liver/heart/kidneys) and slower to others
• *Protein binding (albumin): drugs bound to proteins are pharmacologically inactive. Only free/unbound proteins of the drug act on body cells. Protein binding allows some of the drug to be stored and released as needed and allows for a consistent blood level and less chances of toxicity. Highly bound drugs have a long duration of action.
• Low albumin - must greater risk for toxicity because there is less protein to adhere to.
• blood brain barrier: capillaries with very tight wall limit the movement of drugs into brain tissue. Protective of CNS but makes treating brain issues more difficult.
• Most drugs cross the placenta and can effect the fetus - same goes with breastfeeding

Question 21

Metabolism

Answer 21

• Biotransformation: drugs are inactivated by the body. Active drugs changed into inactive metabolites and excreted.
• Most drugs are lipid soluble, which aids the movement across cell membrane. Liver enzymes convert fat soluble drugs into water soluble metabolites so they can be excreted by the kidneys.
• Enzyme induction: drugs stimulate liver cells to produce larger amounts of drug metabolizing enzymes.
• Enzyme inhibition: concurrent administration of 2 or more drugs that compete for the same metabolizing enzymes
• *First pass effect: some drugs are extensively metabolized in the liver. Only part reaching the systemic circulation – large first pass effect = a lot of the drug is metabolized in the liver and does not reach the body for use.

Question 22

Excretion

Answer 22

• Elimination of drug from the body by the kidney unchanged or as metabolites and excreted in the urine.
• oral drugs that are not absorbed are excreted via the bowel.
• serum drug level: when the lab can actually measure the amount of drug in the blood at a particular time and can indicate onset/peak/duration of the drug action
• serum half life: the time required for the serum concentration of the drug to decrease by half (50%). Determined by the drug’s rate of metabolism.
• A drug with a short half life requires frequent administration.
• When a drug is given at a stable dose, 4-5 half lives are required to achieve a steady state concentration - that’s why some drugs take several days to become therapeutic.

Question 23

Variable that affect drug action

Answer 23

• Dosage: low or high = bad
• Route: IV = fast; po = slow
• Drug-Diet: Drug dependent - some drugs should be taken with food .. some without.
• Drug-drug interactions:
  
  • additive: two drugs with similar actions creating a bigger effect
  • synergism: two drugs with different sites/mechanism of actions producing a greater effect when taken together
  • interference: one drug disrupts the metabolizing effect of another drug
  • displacement: one drug displaces another drug from its plasma protein binding site, which increases the effect of the displaced drug

Question 24

Common adverse effects

Answer 24

• CNS - confusion or stimulation
• GI - N/V/D
• Hematologic - bleeding
• Hepatotoxicity - liver toxicity
• Nephrotoxicity - kidney toxicity
• Hypersensitivity - can occur with any drug
• Fever - inflammatory response
• Idiosyncrasy - unexpected reaction when given the first time
• Drug dependence - psychological/physiological
• Carcinogenicity - ability to cause cancer
• Teratogenicity - abnormal fetal development
• Tolerance - body getting used to it
• Cross tolerance - tolerance to pharmacological related drugs

Question 25

Administration responsibilities

Answer 25

Five rights: drug, dose, patient, route time

Legal order: name, drug, dose, route, frequency plus date, time, signature of ordering prescriber