Drugs For Treating Infection Flashcards
1
Q
Role for Anti-Inflammatory Drugs
A
- When infected, the body will initiate both inflammatory and immunological responses.
~ Exposure to Pathogen
~ Damage Caused by Pathogen
~ Damage caused by excessive immune
response. - Drugs that treat inflammation are always good choices to treat many of the signs and symptoms associated with infection.
~ Fever
~ Headache
~ Aches and Pains
~ Airway Congestion (with respiratory
infection)
> Swollen Tissues
> Exudate
> Mucus
2
Q
Antimicrobials
A
- Any drug used to treat microorganism infection.
~ Bacteria
~ Virus
~ Fungus
3
Q
Bacteria
A
- Forms of bacterial disease
~ Directly damaging cells by release of
exotoxins
> Initiates inflammatory response
~ Binding to cells
> Initiates an inflammatory
response by triggering the release
of HT
4
Q
Antibiotics
A
- Substances that kill (bactericidal) or slow the growth of bacteria (bacteriostatic)
~ Bacteria are similar to human cells,
but there are significant differences
that antibiotics take advantage
> Cell Wall
> Protein Synthesis
> DNA Synthesis - Antibiotics are only needed if body can’t kill it on its own
5
Q
How are antibiotics that only slow growth effective in treatment of infection?
A
It lets the immune system catch up/let it do what it does
6
Q
Antibiotics General Classes: Narrow Spectrum
A
- Specific to a specific range or type of bacteria
~ Gram + = absorb a dye (“Gram Stain”)
> Membrane inside cell wall
~ Gram - = doesn’t absorb dye
> Membrane outside cell wall
7
Q
Antibiotics General Classes: Extended Spectrum
A
- Effective against gram positive and some gram negative bacteria.
8
Q
Antibiotics General Classes: Broad Spectrum
A
- Effective against a wide range of bacteria.
9
Q
Antibiotics: Sulfonamides (Sulfa-Drugs)
A
- Bacteriostatic (Broad Spectrum)
- Interferes with bacteria protein synthesis decreasing reproduction.
- Not used as first line of treatment due to resistance and side-effects.
~ Bacteria is not affected by drug
10
Q
Antibiotics Sulfonamides: Adverse Reactions
A
- Crystalization in the kidney
- Skin Rash
- Anaphylactic Shock
- Photosensitivity
~ Skin is sensitive to the sun when not
usually and results in a pretty bad
sunburn
11
Q
Antibiotics: Penicillins
A
- Have a chemical structure (Beta-lactam ring) that allows binding to bacteria cell wall.
- Bactericidal interrupts synthesis of the cell wall
- Old form (penicillin-G) effective only against Gram positive bacteria (due to cell wall being the outermost layer)
- Distributes into most tissues.
12
Q
Antibiotics: Penicillins Old Form vs New Form
A
- Most of old form inactivated by stomach acid
- Can also be inactivated by an enzyme produced by bacteria (penilinase) that breaks down the Beta-lactam ring
~ New forms more stable in stomach
acid, are resistant to penicillinase and
are wider spectrum
~ Some penicillins are combined with
another drug that inhibits
penicillinase.
> Augmentin - Amoxicillin +
Clavulanate
13
Q
Antibiotics: Penicillin Allergy
A
- 10% of population allergic.
~ Skin Rash
~ Anaphylactic Shock - If allergic to one form of penicillin, all others should be avoided
14
Q
Antibiotics: Macrolides
A
- Bacteriostatic-narrow to broad spectrum
- Interferes with bacteria protein synthesis decreasing reproduction.
- Enter via active transport
- Erythromycin (E-Mycin)
- Clarithromycin (Biaxin)
- Azithromycin (Zithromax)
- Vancomycin
15
Q
Antibiotics: Macrolides Adverse Effects
A
- Heartburn
- Nausea
- Vomiting
- Taking with food can lessen GI problems, but can decrease absorption
~ Decrease absorption due to binding
with minerals
> Calcium
> Magnesium
> Zinc
> Iron
16
Q
Antibiotics: Tetracyclines
A
- Bacteriostatic - broad spectrum
~ Intereres with bacteria protein
synthesis decreasing reproduction.
~ Enter bacteria via active transport. - Not used as first line of treatment due to resistance and side-effects. Used mostly as an alternative in patients with allergies to more effective drugs.
- Still used as primary treatment for some diseases:
~ Rocky Mountain Spotted Fever
~ Cholera
~ Lyme Disease
~ Some forms of Pneumonia
~ Stomach Ulcer Caused by Bacteria
~ Acne
17
Q
Antibiotics: Tetracyclines Absorption
A
- Bind to minerals:
~ Calcium
~ Magnesium
~ Aluminum
~ Zinc
~ Iron - If binding occurs in the Gl tract absorption will be reduced.
~ Should be taken 1-2 hours before a
meal. - Can bind to calcium used to build bones and tooth enamel
~ Not used for children under 8 or
pregnant women - Taking with food can lessen GI problems, but can decrease absorption
18
Q
Antibiotics: Tetracyclines Adverse Effects
A
- Heart burn
- Nausea
- Vomiting
- Diarrhea
- Photosensitivity
19
Q
Antibiotics: Cephalosporins
A
- Very similar to penicillins:
~ Have a chemical structure (Beta-
lactam ring) that allows binding to
bacteria cell wall.
~ Bactericidal interrupts synthesis of cell
wall
~ Bacteria produce an enzyme
(cephalosporinase) that breaks the
Beta-lactam ring
20
Q
Antibiotics: Cephalosporins vs Penicillin
A
- Cephalosporins are better for people no allergic to penicillin
- Allergic reaction especially serious reaction is very rare
- Stomach acid does it break it down as easily
21
Q
Antibiotics: Cephalosporins Generations
A
- First Generation (oldest)
~ Effective against Gram positive
bacteria. - Second Generation
~ Extended Spectrum
~ Somewhat resistant to
cephalosporinase. - Third Generation
~ Broader spectrum and much more
cephalosporinase resistant. - Fourth Generation (newest)
~ Broad spectrum and best resistance
to cephalosporinase (the protein
bacteria makes) = very good
22
Q
Antibiotics: Fluoroquinolones
A
- Bactericidal - Broad Spectrum
~ Inhibits DNA synthesis.
~ Penetrates into most tissues. - Highly effective, orally administered.
- Can bind to certain minerals so should not be taken with food.
23
Q
Antibiotics: Fluoroquinolones Adverse Reactions
A
- Most are very mild.
~ Nausea
~ Vomiting
~ Headache
~ Dizziness
~ Photosensitivity
~ Rash - Musculoskeletal (rare)
~ Tendonitis/Tendon Rupture (more
common in the old or those taking
corticosteroids)
~ Cartilage Defects (especially bad for
the young)
24
Q
Antibiotics: Selection Factors
A
- Identification of Microorganisms
~ Experience and knowing which types
of bacteria or other microorganisms
typically infect certain areas or cause
specific diseases
~ Lab (culture) results especially in the
case of severe infection. - Site of Infection
~ Drugs must be able to penetrate site
of infection.
> Ex. In the case of cerebrospinal
fluid infection drug must be able
to cross blood-brain barrier. - The Patient
~ Drug Allergy
~ Age
~ Existence of other diseases.
25
Q
Why are Gram + bacterial infections more common?
A
They’re easier to treat
26
Q
Antibiotic Drug Resistance
A
- Genetic make-up of an organism changes to give it an advantage when exposed to antibiotics.
~ Mutation
~ Transfer of genetic material.
> Bacterium to Bacterium
> Virus to Bacterium
27
Q
Antibiotic Drug Resistance: Mechanisms
A
- Production of an enzyme that destroys the beta-lactum ring
- Modify binding sites so drug cannot bind.
- Modify transport proteins so drugs cannot enter.
- Modify protein/DNA production.
28
Q
Superinfections
A
- It is normal to have a number of bacteria living in and on the human body.
- When antibiotics are given to treat an infection, they can also kill those that are normally occurring/do not cause infection.
- If a drug resistant bacterium remains, it can take over and cause a difficulty to treat infection
- Bad bacteria multiplies because it no longer had to compete for resources with “good” bacteria
29
Q
Virus
A
- RNA/DNA contained in a protein shell or lipid layer.
- Do not engage in metabolism or reproduce independently, must attach to living cells.
~ Divert cells’ capacities to synthesize
virus nucleic acids and proteins for
viral replication.
30
Q
Forms of Viral Disease
A
- Kill Infected Cells
- Interfere with a cell’s function.
- Cause Cells to Proliferate
~ Human Papillomavirus/Warts
~ Cause Cancer
~ Hepatitis - Liver Cancer
31
Q
Antiviral Agents
A
- Very difficult to develop drugs that kill virus since virus uses a host cell to reproduce and does not take part in living cell processes on its own.
~ Cannot exploit differences as easily as
bacteria
> If it kills the virus it will likely kill
normal cells.
> Few Strategies
• Keep virus from binding or
passing genetic RNA/DNA into
cell
• Inhibit enzymes virus uses
within cell to build RNA/DNA
• Inhibit release of new
RNA/DNA/virus from cell
32
Q
Antiviral Agents
A
- Some antiviral drugs have structures similar to RNA/DNA building blocks to stop RNA/DNA production
~ Adenine
~ Guanine
~ Thymine
~ Cytosine - Drugs are fairly specific and available for;
~ Herpes
~ Flu
~ Hepatitis
~ HIV
33
Q
Antiviral Agents Adverse Reactions
A
- Weight Loss
- Nausea
- Anxiety
- Lightheadedness
- Insomnia
34
Q
Fungus
A
- More complex than bacteria.
~ Have an actual nucleus.
~ Have advanced organelles.
~ Also have a cell wall - If it looks like our cells = really bad
35
Q
Anti-Fungal Agents
A
- Fungi processes are very similar to human cells, more so than bacteria.
- Systemic infections are more rare than superficial (skin) infections, but can be fatal.
36
Q
Anti-Fungal Agents: Systemic Infections
A
- Systematic infections can occur by
introducing fungus during invasive
procedure or is inhaling fungus
~ After infecting the lungs the fungus
can spread to other organs and
become life-threatening.
~ Those who are immunocompromised
or taking immunosuppressive drugs
are most susceptible.
37
Q
Anti-Fungal Agents: Drug Action
A
- Drug action is to disrupt the fungus cell wall causing leakage of cellular content
- Drugs Available
~ Amphotericin B - Fungizone
~ Ketoconazole - Mylan
~ Fluconazole - Diflucan
~ Itraconazole - Sporanox
38
Q
Anti-Fungal Agents: Adverse Effects
A
- Nephrotoxicity (kidney)
- Hepatotoxicity (liver)
- Headache
- Abdominal Pain
