Introduction to Pharmacology

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Introduction to Pharmacology

• EMS Technology
• Temple College

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Topics

• Fundamental Drug Information
• Drug Study
• Pharmacokinetics
• Pharmacodynamics
• Drug Classes Classifications

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Fundamental Drug Information -Sources of Drugs

• Plants
• Animals and humans
• Minerals or mineral products
• Microorganisms
• Synthetics

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Fundamental Drug Information -Drug Names

• Chemical
• Generic (non-proprietary)
• Trade
• Official

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Fundamental Drug Information - Drug Naming Example

• Chemical ethyl-1-methyl-4-plenylisonipecotate
  hydrochloride
• Generic meperidine hydrochloride
• Trade Demerol Hydrochloride
• Office meperidine hydrochloride USP

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Fundamental Drug Information -Standards and
Legislation

• 1906 Pure Food Drug Act
• 1914 Harrison Narcotic Act
• 1938 Food, Drug Cosmetic Act
• 1970 Controlled Substances Act

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Fundamental Drug Information -Regulatory Agencies

• Drug Enforcement Agency
• Food Drug Administration
• Public Health Service
• Federal Trade Commission

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Fundamental Drug Information -Drug References

• Package Inserts
• Drug Reference Books
• PDR
• Others

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Drug Study

• Pharmacokinetics
• the study of the movement of drugs in the body
  including the processes of absorption,
  distribution, biotransformation and excretion
• Pharmacodynamics
• the study of the mechanisms of action of drugs
  and other biochemical and physiologic effects of
  the drug

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Pharmacokinetics

• Drug Absorption
• Routes of Administration
• Distribution
• Biotransformation
• Excretion

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Pharmacokinetics - Drug Absorption

• Cell Membrane
• Absorbing surface
• Blood flow
• Solubility
• Environmental pH
• Concentration

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Pharmacokinetics - Routes of Administration

• Enteral
• Pulmonary
• Topical
• Parenteral

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Drug Administration - Parenteral Rate

• Subcutaneous
• Intramuscular
• Endotracheal
• IV/IO

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Pharmacokinetics - Drug Distribution

• Effectors
• Reservoirs
• Barriers

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Pharmacokinetics -Biotransformation

• Breaking down / Detoxification
• Liver is primary source
• First-pass metabolism
• Hepatic dysfunction may decrease metabolism

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Pharmacokinetics - Excretion

• Kidneys are primary source
• Passive glomerular filtration
• Active tubular transport
• Partial reabsorption
• Hemodialysis
• Other sources of excretion

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Pharmacodynamics

• Drug Receptor Interaction
• Drug Response Relationship
• Half-life
• Therapeutic Index

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Pharmacodynamics - Influencing Factors

• Age
• Body mass
• Gender
• Pathological state
• Genetic factors
• Psychological factors

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Pharmacodynamics - Drug Receptor Interaction

• Lock and Key Concept
• Agonists
• Antagonists
• Competitive

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Pharmacodynamics -Drug Response Relationship

• Therapeutic levels
• Front Loading vs. maintenance doses

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Pharmacodynamics -Biological Half-life (t1/2)

• Amount of time required to excrete 1/2 of total
  amount.
• Complete elimination in 5 iterations
• Shorter t1/2 may need more frequent doses
• Hepatic disease may increase t1/2

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Pharmacodynamics -Therapeutic Index

• Relative safety of drug
• Good MUCH greater than 1
• Bad Closer to 1

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Pharmacology Study - Drug Cards

• Trade and Generic Names
• Class / Classification
• Description/Mechanism
• Indications
• Contraindications
• Adverse Reactions
• Dose/Route

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Drug Classes -Examples

• Narcotics Analgesics Antagonists
• Non-narcotic analgesics (NSAIDS)
• Anti-anxiety, Sedative-Hypnotics
• Adrenergics
• Cardiac Glycosides

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Drug Classes

• Category based upon Therapeutic Intent
• What it is used to treat? (e.g. Antihypertensive)
• Category based upon Mechanism or Effect
• What does it do? (Vasodilator)
• Category based upon the chemical structure
• What is its chemical make-up? (halogenated gas)

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Drug Classes - Cardiac Antidysrhythmics

• Class I (A, B, and C)
• Effect conduction velocity
• Class II
• Beta-blockers
• Class III
• Adrenergic agonist-antagonist
• Class IV
• Calcium channel blockers

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Drug Classes - Cardiac Antidysrhythmics Examples

• Class IA
• Procainamide, Disopyramide, Quinidine
• Class IB
• Lidocaine, Tocainide, Mexiletine, Dilantin
  (Phenytoin)
• Class IC
• Encainide, Lorcainide, Flecainide

• Class II
• Propranolol, Labetalol, Atenolol
• Class III
• Bretylium, Amiodarone
• Class IV
• Diltiazem, Verapamil, Nifedipine

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Drug Classes - Classes of Antihypertensives

• Diuretics (Furosemide, Hydrochlorothiazide)
• Sympatholytics (Prazosin, Propranolol, Labetalol)
• Vasodilators (NTG, Hyperstat)
• ACE inhibitors (Vasotec, Capoten)
• Calcium channel blockers (Verapamil, Nifedipine)

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Other Drug Classes

• Bronchodilators
• Sympathomimetics parasympatholytics
• Xanthines (Aminophylline Theophylline)
• Steroids (methylprednisolone)
• Emetics Antiemetics (Phenergan, Ipecac)