NEU 365D: Principles of Drug Action (Exam I) || A+ Certified.
What is pharmacology? correct answers Pharmacology deals with the fate and actions of drugs in
the body. It overlaps with pharmacy (preparation of drugs) and therapeutics.
What is a drug? correct answers Any substance, other than a normal constituent of the body or
one required for normal bodily function that, when introduced into an organism, has the effect of
altering bodily functions.
Ex: Pencillin and LSD are drugs. Vitamin C is a food, except in high doses (to alter fibroblast
activity). Hydrocortisone secreted by the adrenal cortex is a hormone, but in high doses is a drug.
Drug classifications: Natural preparations (galenticals) correct answers Crude preparations
obtained by drying or extracting plant or animal materials. May date back to prehistoric times.
Ex: Digitalis and desiccated thyroid
Drug classifications: Pure Compounds correct answers Isolated from natural sources by physical
and chemical extraction and purification.
Ex: Morphine (first one purified in 1805), modern drugs like penicillin from molds, anticancer
drugs (vinblastine and vincristine).
Drug classifications: Semisynthetic Compounds correct answers Obtained by chemical
modification of pure compounds obtained from natural sources. These are made in the hope that
they will yirld major improvements of the parent compound with respect to potency, specificity,
and duration of action.
Ex: Acetylating two hydroxyl groups of morphine yields diacetylmorphine (heroin) & changing
side group of penicillin yields oxacillin.
Drug classifications: Purely Synthetic Compounds correct answers Most recently developed
class of drugs. Some were developed for a purpose and their medical use was discovered
accidentally (barbiturates, benzodiazepines, disulfuram). Others were synthesized based on
knowledge gained from semisynthetic compounds to produce custom-designed molecules.
,How are humans exposed to drugs? correct answers *Medical Prescriptions
*Over-the-Counter Sales (cough syrups, analgesics)
*Nonmedical Use (alcohol, tobacco, illicit drugs)
*Industrial Use (solvents, flavorings, colorings, fillers)
*Agricultural Use (insecticides, herbicides)
*Accidental Dosing (aflatoxin on peanuts, ergot on rye)
*Intentional Dosing (homicide, suicide)
Goal of Drug Administration correct answers Get an adequate (but not toxic) concentration of
drug to the necessary site of action as quickly as possible and to maintain that concentration as
continuously and evenly as possible
Routes of Drug Administration: Topical correct answers Simplest route of drug administration,
most often to an accessible body surface. Drugs applied to mucus membranes are quickly
absorbed and may have systemic effects; topical use refers to the application of small volumes
and low enough concentrations to ensure the drug ONLY acts at the desired local site.
Ex: Creams or ointments to skin, eye/nose drops, solutions or sprays for mouth, throat, rectum,
vagina, and urethra.
Routes of Drug Administration: Injection into Body Cavities correct answers Drugs may be
injected directly into body caities for localized actions at those sites.
Ex: Corticosteroids into joints, antibiotics into abscesses
Routes of Drug Administration: Intrathecal Injection correct answers Injections into the
cerebrospinal fluid bypass the blood-brain barrier and the blood-CSF barrier, yielding high local
concentrations without producing significant blood levels.
, Routes of Drug Administration: Percutaneous correct answers Drug absorption through the skin,
for the purpose of a systemic effect.
Absorption is proportional to lipid solubility and can be enhanced by suspending drug in an oily
vehicle.
Ex: Nitroglycerin (angina), scopolamine (motion sickness), nicotine (smoking cessation).
Poisonings with insecticides often occur via this route.
Routes of Drug Administration: Gastrointestinal (GI) Tract correct answers *Oral mucosa
(sublingual): Very rapid absorption and drugs are not subject to gastric and intestinal digestive
juices and also not subject to immediate passage through the liver (the first pass effect) before
entering the systemic circulation. Ex: nitroglycerin tablets
*Stomach & Intestine (oral, per os, p.o., PO): Absorption from the upper GI tract depends on pH,
gastric emptying rate, intestinal motility, solubility (dissolution) of solid drugs, concentration of
drug solutions, stability of drugs in GI fluids.
*Rectal mucosa (suppositories): Useful for unconscious or nauseous patients or when drug has
an objectionable taste or would be degraded by acid or digestive enzymes. Also useful in treating
infants. No first pass effect.
Routes of Drug Administration: Pulmonary epithelium correct answers Inhalation of gases,
vapors and aerosols. Fast onset of of action.
Ex: Volatile anaesthetics, anti-asthmatic medications.
Routes of Drug Administration: Injections correct answers Advantages: rapid & predictable
absorption
Disadvantages: strict asepsis, pain, expense, psychological difficulty in self-injection
Types of Injections:
*Subcutaneous (S.C): Can only be used for non-irritating drugs in small volumes. Provides for
slow and even drug absorption, yielding sustained drug effects. Ex: insulin, vaccines, opioids
(spin popping)
What is pharmacology? correct answers Pharmacology deals with the fate and actions of drugs in
the body. It overlaps with pharmacy (preparation of drugs) and therapeutics.
What is a drug? correct answers Any substance, other than a normal constituent of the body or
one required for normal bodily function that, when introduced into an organism, has the effect of
altering bodily functions.
Ex: Pencillin and LSD are drugs. Vitamin C is a food, except in high doses (to alter fibroblast
activity). Hydrocortisone secreted by the adrenal cortex is a hormone, but in high doses is a drug.
Drug classifications: Natural preparations (galenticals) correct answers Crude preparations
obtained by drying or extracting plant or animal materials. May date back to prehistoric times.
Ex: Digitalis and desiccated thyroid
Drug classifications: Pure Compounds correct answers Isolated from natural sources by physical
and chemical extraction and purification.
Ex: Morphine (first one purified in 1805), modern drugs like penicillin from molds, anticancer
drugs (vinblastine and vincristine).
Drug classifications: Semisynthetic Compounds correct answers Obtained by chemical
modification of pure compounds obtained from natural sources. These are made in the hope that
they will yirld major improvements of the parent compound with respect to potency, specificity,
and duration of action.
Ex: Acetylating two hydroxyl groups of morphine yields diacetylmorphine (heroin) & changing
side group of penicillin yields oxacillin.
Drug classifications: Purely Synthetic Compounds correct answers Most recently developed
class of drugs. Some were developed for a purpose and their medical use was discovered
accidentally (barbiturates, benzodiazepines, disulfuram). Others were synthesized based on
knowledge gained from semisynthetic compounds to produce custom-designed molecules.
,How are humans exposed to drugs? correct answers *Medical Prescriptions
*Over-the-Counter Sales (cough syrups, analgesics)
*Nonmedical Use (alcohol, tobacco, illicit drugs)
*Industrial Use (solvents, flavorings, colorings, fillers)
*Agricultural Use (insecticides, herbicides)
*Accidental Dosing (aflatoxin on peanuts, ergot on rye)
*Intentional Dosing (homicide, suicide)
Goal of Drug Administration correct answers Get an adequate (but not toxic) concentration of
drug to the necessary site of action as quickly as possible and to maintain that concentration as
continuously and evenly as possible
Routes of Drug Administration: Topical correct answers Simplest route of drug administration,
most often to an accessible body surface. Drugs applied to mucus membranes are quickly
absorbed and may have systemic effects; topical use refers to the application of small volumes
and low enough concentrations to ensure the drug ONLY acts at the desired local site.
Ex: Creams or ointments to skin, eye/nose drops, solutions or sprays for mouth, throat, rectum,
vagina, and urethra.
Routes of Drug Administration: Injection into Body Cavities correct answers Drugs may be
injected directly into body caities for localized actions at those sites.
Ex: Corticosteroids into joints, antibiotics into abscesses
Routes of Drug Administration: Intrathecal Injection correct answers Injections into the
cerebrospinal fluid bypass the blood-brain barrier and the blood-CSF barrier, yielding high local
concentrations without producing significant blood levels.
, Routes of Drug Administration: Percutaneous correct answers Drug absorption through the skin,
for the purpose of a systemic effect.
Absorption is proportional to lipid solubility and can be enhanced by suspending drug in an oily
vehicle.
Ex: Nitroglycerin (angina), scopolamine (motion sickness), nicotine (smoking cessation).
Poisonings with insecticides often occur via this route.
Routes of Drug Administration: Gastrointestinal (GI) Tract correct answers *Oral mucosa
(sublingual): Very rapid absorption and drugs are not subject to gastric and intestinal digestive
juices and also not subject to immediate passage through the liver (the first pass effect) before
entering the systemic circulation. Ex: nitroglycerin tablets
*Stomach & Intestine (oral, per os, p.o., PO): Absorption from the upper GI tract depends on pH,
gastric emptying rate, intestinal motility, solubility (dissolution) of solid drugs, concentration of
drug solutions, stability of drugs in GI fluids.
*Rectal mucosa (suppositories): Useful for unconscious or nauseous patients or when drug has
an objectionable taste or would be degraded by acid or digestive enzymes. Also useful in treating
infants. No first pass effect.
Routes of Drug Administration: Pulmonary epithelium correct answers Inhalation of gases,
vapors and aerosols. Fast onset of of action.
Ex: Volatile anaesthetics, anti-asthmatic medications.
Routes of Drug Administration: Injections correct answers Advantages: rapid & predictable
absorption
Disadvantages: strict asepsis, pain, expense, psychological difficulty in self-injection
Types of Injections:
*Subcutaneous (S.C): Can only be used for non-irritating drugs in small volumes. Provides for
slow and even drug absorption, yielding sustained drug effects. Ex: insulin, vaccines, opioids
(spin popping)
