Download Unit I

Unit I
Introduction
to
Pharmacology
EFFECTS OF DRUGS
DEFINE:
1.
2.
3.
4.
5.
Therapeutic effect
Side effect
Toxic effect
Lethal effect
Allergic reaction
PHARMACEUTICAL TERMS
DEFINE:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Mechanism of action (MOA)
Site of action
Receptor Site
Lock and Key
Agonist drug
Antagonist drug (blocker)
Physical Dependence
Psychological Dependence
Tolerance
DRUG INTERACTIONS
Additive effect - when the combined effect of 2 drugs each producing the same biological
response by the same MOA, is = to the sum of their individual effects.
1+1=2
Synergistic effect - when 2 drugs having the same biological response, NOT by the same
MOA, are given together, the effect is greater than the sum of the effects of each drug if
given alone.
1+1=3
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NEW DRUG DEVELOPMENT
 FDA
 Investigational New Drug Application (INDA)
– Chemical Name
– Generic Name
 4 Phases Human Studies
 Informed Consent (I.C.)
Purpose:
a. involves explanation of the purpose of the study
b. procedures to be used
c. risks involved
 PHASE I: Small # of healthy volunteers
Determine:
a. optimal dosage range
b. pharmacokinetics
c. several tests – blood samples
 PHASE II: Small # of volunteers that have the disease/condition.
Determine:
a. drug’s effectiveness
b. side effects
 PHASE III: Large # of patients at medical research centers.
Determine:
a. infrequent and rare side effects
b. look for risks of drug
c. dosage range, safety, effectiveness
 PHASE IV: (Optional) – used to compare new drug with already existing medication in that
class.
 New drug application (NDA):
 National Drug Code (NDC):
– brand name or trade
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DRUG NOMENCLATURE
Chemical Name: 7-chloro-1, 3-dihydro-1-methyl-5-phenyl-2H, 1, 4-Benzudiazepin2-one
Generic Name:
Diazepam
Trade Name or Brand Name: Valium®
GENERAL EQUIVALENT:
A. PHARMACEUTICALLY EQUIVALENT
B. THERAPEUTICALLY EQUIVALENT
A. PHARMACEUTICALLY – drug product that has identical amounts of the same active
chemical ingredients in the same dosage form that has the same
Strength
Quality
Purity
B. THERAPEUTICALLY – when drug administered in the same amount, it will provide the
same therapeutic effect – including duration and intensity.
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
Dose-Response Curve
Figure 1.3 A typical dose-response curve

Time-Response Curve
Figure 1.4 A typical time-response curve
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I. Dose – Response Curve:
Purpose:
1) To compare and evaluate a drug response among different drugs that are similar.
2) Potency is determined here as well. The strength or concentration needed to produce a
desired (therapeutic) effect.
II. Time – Response Curve:
Purpose: To determine frequency of administration of medication in order to maintain an
effective drug response.
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DRUG LEGISLATION
DEFINE:
Pure Food and Drug Act of (1906):
– Designed “The U.S. Pharmacopeia” (USP) which set up an official standard for drugs.
Harrison Narcotic Act (1914):
Food, Drug and Cosmetic Act of (1938):
Durham-Humphrey Amendment of (1952): – “Birth of the Legend”
Kefauver-Harris Amendment of (1962):
Controlled Substance Act of (1970):
DEA (1973):
Orphan Drug Act (1983):
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How To Figure Out If a DEA Number Given Is Legal
The authenticity of a DEA prescriber registration number can be confirmed by the following
formula:
Step 1: Add the 1st , 3rd, and 5th digits of the DEA number;
Step 2: Add the 2nd, 4th, and 6th digits;
Step 3: Multiply the sum of Step 2 by 2; AND
Step 4: Add the 2 numbers from Step 1 and Step 3 together.
Step 5: The last digit of this sum is the same as the last digit of the DEA prescriber registration
number.
NOTE: There are 2 letters that proceed a DEA number. The first letter is either an A or a B.
The second letter is the first letter of the prescriber’s last name.
EXAMPLE: AS1234563
This is the DEA number for Dr. Alfred Smith.
1:
2:
3:
4:
1 + 3 + 5 = 9;
2 + 4 + 6 = 12;
12 X 2 = 24;
9 + 24 = 33.
AS1234563
This is a legal DEA number.
*Be able to figure out if a DEA number is legal.
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Controlled Substances
Schedule I
Drugs
Heroin, LSD, Marijuana
Schedule II
Meperidine®
Pentobarbital
Percodan®
Mepergan Fortis®
Amphetamines
Ritalin®
Schedule III
Fiorinal®
Tylenol c codeine®
Empirin c codeine®
Vicodin®
Marinol®
Schedule IV
Dalmane®
Librium®
Valium®
Tranxene®
Schedule V
Lomotil
Robitussin AC
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PHARMACOKINETICS
A. Absorption
1. Diffusion
2. Filtration
3. Osmosis
Three factors affecting the rate of absorption
1. Solubility of the drugs
2. Route of Administration
a. Enteral –
b. Parenteral –
c. Percutaneous –
3. Amount of blood flow through the tissues
B. Distribution
Three factors influencing distribution
1. Plasma Proteins:
2. Blood Flow:
3. Blood-Brain Barrier
C. Metabolism – liver
Enzyme:
DMMS – Drug microsomal metabolizing system
1. Enzyme Inducers –
2. Enzyme Inhibitors
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Metabolism
Enzyme Inducers
Smoking
Phenobarbital
Phenytoin
Carbamazapine
Chronic alcohol ingestion
Enzyme Inhibitors
Cimetidine (Tagamet®)
Erythromycin
Allopurinol
Calcium Channel Blockers
Fluoxetine (Prozac®)
Short-term Acute alcohol ingestion
FIRST-PASS EFFECT
Routes that avoid the first-pass effect:
sublingual
intravenous
vaginally
inhalation
transdermal
buccal
subcutaneous
topical
intraocular
intramuscular
D. Excretion:
1.
2.
3.
4.
Kidneys*
GI Tract
Lungs
Sweat
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Types of Interactions
A.
Drug-Drug: when one drug increases or decreases the effect of another drug or both
drugs. (Enzyme induction or enzyme inhibitor)
EX: glyburide and alcohol
Effect: acute-inhibition of enzymes-hypoglycemia
chronic-enzyme inducer- hyperglycemia
B.
Drug-Disease: when a drug interferes with the pathophysiology of a disease.
EX: Diabetes mellitus and prednisone (a steroid)
Effect: increases blood sugar levels
C.
Drug-Food/Drink: When food/drink increases or decreases the effects of a drug.
EX: MAO Inhibitors and bean, cheese, or wine
Effect: hypertensive crisis or stroke
D.
Disease-Food/Drink: When food/drink is consumed and causes the disease/condition to
worsen.
EX: Gout patient consuming sardines, anchovies, liver, cheese, beer, or
wine
Effect: more uric acid to accumulate in joints causing pain
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Types of Doses
Usual Dose - dose that is generally appropriate for the patient.
Loading Dose - the first dose given, which is higher than the other doses to
elevate the blood level quickly. IV route is used.
Minimum Dose effect.
smallest amount of drug that will produce a therapeutic
Maximum Dose -
largest amount of a drug that will produce a desired effect.
Maintenance Dose therapeutic state.
dose required to keep drug blood level at steady
Initial Dose - any first dose of a drug.
Lethal Dose - dose that causes death.
Toxic Dose - dose that will produce harmful effects.
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3 Routes of Entry into the Body
DEFINE:
A.
Enteral Route –
1. Oral Administration –
2. Nasogastric Administration –
3. Rectal Administration –
DEFINE:
Oral Medication Forms – Enteral route
A.
Tablets
1. Scored tablets
2. Enteric - coated tablets
B.
Capsules – time-released (sustained released)
C.
Lozenges
D.
Elixirs
E.
Emulsion
F.
Suspensions
G.
Syrups
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B. Parenteral Route
A. Intradermal
–Slow absorption due to a decrease in blood supply
B.
Subcutaneous (SUB Q)
–Medication is slowly, but completely absorbed
–Slow onset of action, but long duration
Parenteral Route
C.
D.
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Intramuscular
–Rapid and complete absorption
Intravenous (IV)
–Fastest way of getting into our system
–Increase onset of action
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C. Percutaneous Route
* 7 areas associated with mucous membranes:
* Identify location for the following:
A.
B.
C.
D.
E.
F.
G.
Sublingual
Buccal
Eye
Ears
Nose
Inhaled into Lungs
Vaginal
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Percutaneous route: absorption of medication through the skin or mucous membranes.
Types of Topical Medications
1.
Creams - a semi-solid mixture that contains medication in a water soluble base.
Ex:
2.
Ointments - a semi-solid preparation of medication in an oily base, the base being
petrolatum. The ointment is oily in texture, but makes for good, long skin contact that is
not easily removed.
Ex:
3.
Lotions - an aqueous preparation containing suspended medication that soothes or cleans
the skin. Must shake well.
Ex:
4.
Powders - medication in talc form or in a talc base that is used for drying, cooling, or
protecting the skin.
Ex:
5.
Patches - this is placed on the skin, a semipermeable membrane is present between the
patch and the skin that contains medication that is released over a 24 hour period; the
dosage released depends on the concentration of the patch.
Ex:
6.
Astringents: alcohol based medication for cooling or drying the skin.
Ex:
7.
Shampoos - medication for the scalp/hair in an aqueous or alcohol bases.
Ex: Nizoral
8.
Define Solutions –
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Study Sheet for Exam #1
1.
Review definitions:
–Pharmacology
–Site of Action
–Receptor Site
–Mechanism of Action
–Agonist Drug
–Antagonist Drug
–Lock and Key
–Physical Dependence
–Psychological Dependence
–Tolerance
–Therapeutic Effect
–Side Effect
–Toxic Effect
–Additive Effect
–Synergistic Effect
2.
Become familiar with the understanding and meaning of the concepts, enzyme inducers and
enzymes inhibitors.
3.
Be able to identify from drug list which ones are enzyme inducers and enzyme inhibitors.
4.
Pharmacokinetics: define and understanding of concepts:
–Absorption
–Distribution
–Metabolism
–Excretion
–Know the factors that can influence each of these processes
5.
Define Solutions.
6.
Know calibrations on:
a. insulin syringe - 100 units = 1 ml
b. tuberculin syringe - 1cc or ½ cc
c. 3 cc, 10 cc, 20cc syringe
7.
Define percentages and ratios.
8.
Know common equivalents.
9.
Know the difference between an ampule and a vial.
10. Become familiar with the procedure in administering the following:
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–Drawing medication from an ampule and a vial
–Rectal
–Nasogastric
11. Define Gauge:
Rule: “The smaller the number, the larger the needle.”
12. One calculations problem from chapter 13 and 1 bonus problem from reconstitution.
13. Define:
–Diffusion
–Osmosis
–Filtration
–Passive Transport
–Active Transport
14. Know abbreviations: be able to write it out.
15. Become familiar with different route of drug entry into the body and their examples:
A. Enteral–define: 1) oral, 2) nasogastric, 3) rectum
B. Parenteral: intradermal, subcutaneous, intramuscular, intravenous
C. Percutaneous–define
16. Know the three ways to obtain a prescription drug.
17. Know the different parts to a prescription.
18. Who can write prescriptions, ie., MD, Dentist, etc.?
19. Who or what has a DEA#?
20. Be able to define and match drug legislation – dates included
–Harris Narcotic Act
–Durham-Humphrey Amendment
–Kefauver Harris Act
–Federal Food and Drug Act
–Pure Drug and Food Act
–Control Substance Act
–Orphan Drug Act
21. Become familiar with schedule 1-5 and the examples that belong to each. What is the
difference between schedule 1 and schedule 4 or 5?
22. Be able to trace the steps on how a drug becomes reviewed by FDA for public use (New
Drug Development). Phase I – Phase IV.
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23. Know the drug nomenclature process
24. Be able to use and interpret a dose – response curve and a time-response curve.
25. Become familiar with different type of oral medication forms.
–Extended release capsule
–Elixirs
–Tablets vs. Enteric-coated Tablet
–Syrups
–Capsules
–Lozenges
26. Know different type of topical medications
–Creams
–Patches
–Ointments
–Etc.
27. Know type of interactions
28. Know different types of dosing
–Loading Dose
–Maximum Dose
–Etc.
29. Know major areas of pharmacology
–Pharmacodynamic
–Pharmacokinetics
–Pharmacy
–Toxicology
30. Become familiar with the First-Pass Effect and the routes that avoid this effect.
31. Define:
–Bioavailability
–Half-life
–Incompatibility
–Reconstitution
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32. Define:
–Buccal
–Sublingual
–Vaginal
33. Be able to distinguish between the five pregnancy safety categories.
34. Review the Self Pharmacology Test at the back of this packet.
35. Review in “Dimensional Analysis For Meds,” Chapters 5 - 10. Look at Dimensional
Analysis “Worksheet” given at orientation for pages to read, problems to work, and what to
concentrate on for the exam. Become familiar with the concepts. NOTE: Focus on pages
under “Pharmaceutical Dosage Calculations” section in this packet.
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