ANTI-INFECTIVE AGENTS
Roselyn A. Naranjo
Anti-infective Agent
- is
- are
a general
drugs capable
term that
of acting
encompasses
against infection,
antibacterials,
by inhibiting
antibiotics,
the spreadantifungals,
or by killing the
antiprotozoans
infectious agent.
and antivirals.
CHEMOTHERAPHY
-is
of
(or
drugs) to
- -is
isthe
the
use
ofmedicines
chemical
theuse
study
and
use ofsubstances
chemical
treat
disease.
toagents
treat
disease.
In its modern-day
that are selectively
more toxic
use,
it refers
to cytotoxic
drugs used
to the
invading
organism.
-to-can
cells
that have
cancer
or
theinfectious
combination
of
ittreat
isdestroy
the
curecancer
of an
disease
metastasized,
or
to parts of the
these
drugs
into
standardized
without
injury
toaspread
the
host.
body
far away
from the primary
treatment
regimen.
(original) tumor.
Cytotoxic Cells
- a cytotoxic T cell (also known as TC, CTL, TKiller cell or killer T cell) belongs to a sub-group of
T lymphocytes (a type of white blood cell) which
are capable of inducing the death of infected or
somatic tumor cells.
- they kill cells that are infected with viruses (or
other pathogens ), or are otherwise damaged or
dysfunctional.
Selective toxicity
- is the property of certain chemicals to
destroy one form of life without harming
another.
- the cornerstone of modern antimicrobial
chemotherapy.
Paul Ehrlich
- discovered the antibacterial dyes and
parasitic activity of organic arsenical.
Classification of chemotherapeutic Agents
1. Chemical Type
2. Biological Properties
3. Therapeutic indicators
Types of Anti-infective agent according to source:
1. Antibiotics – derived from natural source or semisynthetically prepared.
2. Antimicrobials – produced from synthetic substances.
Classification of Local Anti-infective Agents
1. Antiseptic
- are compounds that kill or prevent the growth of
microorganism when applied to living tissue.
Criteria of an ideal Antiseptic
* exerts rapid and sustained lethal action against microorganism
(narrow and broad spectrum)
* retain activity in the presence of body fus including pus
* non-irritating to tissues
* non-allergenic
* lack systemic toxicity when applied to skin or mucous
membrane
* does not interfere with healing
Classification of Local Anti-infective Agents
2. Disinfectant
- is an agent that prevents infection by the destruction
of pathogenic microorganisms when applied to
inanimate objects
Criteria of an ideal disinfectant
* exerts a rapid lethal action against all potentially pathogenic
microorganisms and spores.
* has good penetrating power into organic matter
* compatible with organic compounds (especially soap)
* not inactivated by living tissues
* non-corrosive
* esthetically desirable (non-staining and odorless)
ALCOHOLS AND RELATED COMPOUNDS
A. Alcohol
- also known as ethanol, wine spirit, Cologne spirit.
- has burning taste and flammable.
- miscible with water and other organic solvents.
- fermentation product from grain and other carbohydrates.
- most widely abused of all recreational drugs.
- metabolized in the liver to aldehyde then to acetic acid and
finally to carbon dioxide and water.
Classification of Local Anti-infective Agents
A. Alcohol
The antibacterial action of alcohol is due to the
denaturing effect on proteins.
coagulates
100% ethyl alcohol
70% ethyl alcohol
Uses:
- antiseptic, preservative, mild counter-irritant or solvent of
pharmaceutical preparations including spirits, tinctures and
fluidextracts.
- rubbing alcohol is used as astringent, rubefacient,
refrigerant and mild local anesthetic.
- alleviate pain of neuralgia by injecting alcohol to nerve and
ganglia.
- used internally in diluted forms as a mild sedative, as a
weak vasodilator, as carminative and as source of energy.
Types of alcohol
Denatured alcohol
- is ethanol that has been rendered unfit for
use in intoxicating beverages by the addition
of other substance.
Completely denatured alcohol
- contains added wood alcohol and benzene
and is unsuitable for either external or internal
use.
Specially denatured alcohol
- is ethanol treated with one or more
substances so that its use may be permitted
for specialized purposes.
Examples are methanol for plant extracts
Iodine in alcohol for tincture of iodine
ALCOHOLS AND RELATED COMPOUNDS
B. Dehydrated Ethanol
- also known as absolute alcohol
- it contains not less than 99% by weight of C2H5OH.
- it is prepared by azeotropic distillation of an ethanol and
benzene mixture.
- it has a very high affinity of water and must be stored in
tightly sealed containers.
- it is use primarily as chemical agent, but it has also been
injected for the local relief of pain in carcinoma and neuralgia.
ALCOHOLS AND RELATED COMPOUNDS
C. Isopropyl alcohol, USP
- it is a clear, colorless liquid having a characteristic odor
and slightly bitter taste. It is considered a suitable
substitute for ethyl alcohol for most external uses, but it
must not be taken internally.
- it is prepared commercially by the sulfuric acid-catalyzed
hydration of propylene.
Uses:

- it is rapidly bactericidal in the
concentration range of 50% to 95%.
- 40% concentration is considered equal
in antiseptic power to a 60% ethanol
concentration.
- Azeotropic isopropyl alcohol, USP is
used by diabetics
To be continued…