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Analgesics
Analgesics
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Analgesics are common pain relievers.
Some analgesics also have
antipyretic properties as well. They
can be used to reduce fever.
Some analgesics are also antiinflammatory drugs. They reduce
inflamation as well
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Classification of Analgesics
Analgesics
Strong
Analgesics
Mild
Analgesics
Aspirin
Ibuprofen
Acetaminophen
Opium
Heroin
Codeine
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Mild Analgesics
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Mild Analgesics include
many over-the-counter
pain relievers and fever
depressants.
Examples of mild
analgesics include aspirin,
acetaminophen, and
ibuprofen.
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Mechanism of Mild
Analgesics
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The mechanism by which
mild analgesics act is still
controversial.
It is believed that they
inhibit the formation of
prostaglandins at the site
of the injury.
Prostaglandins are
involved in the
transmission of pain
signals to the brain
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Aspirin
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Aspirin is a
derivative of
salicyclic acid
Salicyclic acid was
found in the bark of
the willow tree and
was used as a pain
reliever and as a way
to relieve fever
symptoms of
malaria.
Aspirin
Salicyclic Acid
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Aspirin
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In 1899, Felix Hoffman, a chemist from
the Bayer Company, developed a lowcost process to synthesize an ethanoate
ester of salicyclic acid, called aspirin
In the synthesis of aspirin, the ethanoic
acid forms an ester with the alcohol
group on the second carbon
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Aspirin
As a mild analgesic,
aspirin is believed to
inhibit the enzyme,
Prostaglandin
Synthase which is
formed at the site of an
injury.
This inhibits the
production of
prostaglandins which
produce fever and
swelling as well as
transmitting pain signals
to the brain.
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Aspirin -- Uses and
Benefits
 Aspirin is able to reduce pain and fevers
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and dilate blood vessels
Aspirin enlarges blood vessels which
helps prevent blood clots.
This vasodilation of the surface blood
vessels also allows an increase of heat
released which lowers the temperature
of a fever
Aspirin is also taken to prevent
recurring heart attacks
It may also be effective in
preventing prostate cancer
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Side Effects of Aspirin
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Aspirin can irritate the stomach lining which
may lead to ulcers
If aspirin is used over long periods of time,
it may lead to problems with blood clotting
An overdose on aspirin, such as the case
with some arthritis sufferers, may lead to
dizziness, ringing in the ears,
gastrointestinal problems, mental
confusion, and bleeding.
Some people are allergic to aspirin leading
to bronchial asthma
In children under 12 Aspirin has been linked10
Antibacterial and
Antiviral Drugs
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Antibacterials
Bacteria
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Definition
Replication
Shapes
Diseases
Antibacterials
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1.
2.
3.
4.
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1.
2.
Penicillin
Discovery of
Synthesis
Structure
Ways it functions
General
Antibacterials
Problems
Possible solutions
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Characteristics of Bacteria
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Single celled or
non- cellular
Spherical,spiral or
rod–shaped
organisms
Lack chlorophyll
Reproduce by
fission
Important as
pathogens and for
biochemical
properties.
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Infectious Bacteria
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Cocci – Sphericial
Often cause sore throats
and pneumonia
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Bacilli – Rod shaped
Mycolbacterium cause
tuberculosis
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Spirochete – Spiral
shaped
Syphilis, gum infections
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Structure of a Bacterium
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Capsule – Protective layer of
bacteria. made of proteins, sugars,
and lipids
Cell wall – Provides the bacteria with
its shape and structure.
Cell membrane – permeable
membrane that transfers nutrients
and chemicals in and out of the cell.
Cytoplasm – Liquid within the cell
which serves to protect cell parts as
well as move materials throughout the
cell. Contains glycogen, lipids and
other nutrients
Ribosomes – synthesizes proteins.
DNA – Single chromosome controls
the functions of the cell.
Flagella – A tail-like appendage used
for movement.
Pilus – Small hairs whose purpose is
to stick to surfaces. Can also be used
in reproduction.
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Structure a Bacterium
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Bacteria can be either
aerobic or anaerobic
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Aerobic:-- require
oxygen for metabolism.
They are more likely to
infect surface areas
such as the skin and
the respiratory tract.
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Anaerobic – multiply in
oxygen free and in low
oxygen surroundings
such as the intestines.
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Replication by Binary Fission
One cell is split into two separate cells.
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Bacterial Caused Diseases
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Anthrax
Cholera
Plague
Q-Fever
Strep Throat
Staph Infections
Tuberculosis
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The Discovery of Penicillin
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Penicillin was discovered in 1929 by
scientist Alexander Fleming.
He left for vacation with an agar
plate covered with the bacteria
Staphylococcus aureus.
When he returned he noticed that
the fungus, Penicillium, had grown
on the plate
The bacteria colony
surrounding the fungus had
become transparent because
the bacterial cells had
undergone lysis.
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Development of Penicillin
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Several years later Howard Florey and
E.B. Chain stumbled across Fleming’s
research papers and were intrigued by
his findings.
They were convinced that Flemming’s
discovery could save a lot of lives,
prevent pain, and make it much easier
to fight infectious diseases and prevent
other infections.
They developed a way to mass produce
penicillin making it available to soldiers
wounded in world war II.
Florey and Chain were awarded the
Nobel Prize in 1945 for their work on
penicillin.
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Penicillin Structure
Penicillins have a special structure that allows
them to interfere with the formation of the cell
wall when bacteria reproduce
The general structure of penicillin
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How Does it Function?
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Penicillin prevents the cross linking of
small peptide chains in peptidoglycan,
which is the main polymer in bacterial
cell walls.
They do not affect bacteria which already
exist, rather Penicillin’s affect the
synthesis of new bacteria.
The new bacteria grow without the ability
to maintain cell rigidity, making them
susceptible to osmotic lysis.
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The Action of Penicillins
The
amide group in the
beta lactam is more
reactive due to the
strained ring.
The structure of the
beta lactam is similar to
the structures of
cysteine and valine.
The beta lactam binds
to the enzyme that
synthesizes the cell wall
in bacteria, blocking its
action.
As a result the bacteria
rupture and break and
cannot reproduce.
Note the similarities in structure
to the beta lactam.
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Bacterial Immunity to
Penicillin
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Antibiotic Resistance –
Mutated bacteria which are
immune to antibiotics are
more likely to survive when
excessive antibacterials are
used.
Bacteria develop enzymes
known as penicillinases that
destroy or render penicillin
ineffective.
New antibiotics are
developed by changing the R
group side chain.
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Structure of Penicillin
Penicillin is a group of compounds which all contain the
same basic ring structure, known as beta-lactam. It is
comprised of two amino-acids (valine and cyteine) through
a tripeptide intermediate. The third amino acid (the R
group) is replaced by another group, which gives different
characteristics to differing penicillins.
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Narrow Range and Broad
Range Antibiotics
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Narrow range antibiotics target specific
kinds of bacteria. They are usually more potent.
Broad range antibiotics are effective against a wide
range of bacteria.
When doctors diagnose patients suspected of having
bacterial infections, they must first take samples of
body fluids, and try to determine the precise type of
infection.
A broad range antibiotic might be prescribed initially.
Once a bacterial infection is properly diagnosed it may
be appropriate to switch to a narrow range antibiotic.
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Overuse of Penicillin
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Leads to greater immunity of bacteria
to penicillin, since the strongest and
most resistant strains survive.
Greater doses of penicillin are required
to be effective
Danger of developing super bacteria
Kill beneficial bacteria as well as
harmful bacteria
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Penicillin Synthesis
A sterilized growth
medium and an
inoculum of strongly
growing hyphae is
added to stainless
steel fermenters. The
fermenters stirred
continuously and
glucose, nitrate and
sterile air are
periodically added.
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