Transcript Document

Unit 3 Seminar
Dr. Amy Thompson
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Antibiotic Agents
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Produced by living cells or synthetic analog
Kill or inhibit growth of microorganisms
Come from molds, bacteria, and yeasts
Each antibiotic agent has spectrum
Must be taken for full time prescribed
Allergic reactions common
Placed in broad groups: penicillins,
cephalosporins, tetracyclines, macrolides,
quinolones
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Penicillin Agents
• Common treatment for the following:
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Streptococcal and pneumococcal infections
Gonorrhea/Syphilis
Meningitis
Other infections
• General toxicity and side effects
– Allergy
– Abdominal cramping and diarrhea
– Monilia overgrowth
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Beta-Lactam Agents
(Cephalosporin Agents)
• Developed from mold (like penicillin agents)
and have similar side effects(cross-sensitivity)
• Act on young, dividing bacterial cell walls
• Side effects include GI upset, skin rashes
• Divided into four generations by spectrum:
– First-generation―streptococci, some staphylococci, some urinary
– Second-generation—first-generation spectrum plus Haemophilus
influenzae
– Third-generation―gram- negative GI and urinary infections;
reserved for infections that do not respond to other agents
– Fourth-generation—UTI, pyelonephritis, skin, soft tissue, abdomen
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Tetracycline Agents
• Broad-spectrum antibiotic agents
• Effective against many microorganisms,
particularly those infecting respiratory
system and soft tissues
• Most are oral, many parenteral
• Give on empty stomach
• Not given to children or during
pregnancy (stains tooth enamel)
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Macrolide Agents
(Erythromycin Agents)
• Bacteriostatic, effective against
multiplying organisms
– Narrow spectrum
– Generally they are as effective as penicillin and
often used in penicillin-sensitive patients.
• Effective against gram-positive cocci (staph and strep)
• Effective against Bacillus anthracis (anthrax)
– Synthetic agents like azithromycin, clarithromycin,
and dirithromycin have expanded spectrum
activity and are more potent.
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Quinolones and Other
Antibiotic Agents
• Orally effective agents that act differently from
antibiotic agents with a broad spectrum
• Used in infections resistant to older antibiotic agents.
• The drug is eliminated slowly.
– Caution should be used in patients with kidney or liver
impairment, as well as when used in combination with
anticoagulant agents.
• Many antibiotic agents are ototoxic (they can cause
auditory damage) and must be used with caution in
children.
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Sulfonamide Drugs
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Sulfa drugs are also used to treat infection
Synthetic drugs that resemble PABA
Bacterial resistance limits its use
Treat UTI; Haemophilus influenzae ear
infections
• Allergic/hypersensitivity reactions
• Side effects are decreased because of lower
doses and longer action
• May react with thiazide diuretics and
antidiabetic agents.
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Antifungal Agents
• Fungi can survive as parasites because
they do not contain chlorophyll.
• Infections may be simple, as in athlete’s
foot fungal rash or thrush.
• In patients with impaired immune
systems, fungal infections can be life
threatening.
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Antiviral Agents
• A virus enters an intact host cell and is able to
massively reproduce and mutate.
• Unable to kill viruses.
• Used to treat influenza [oseltamivir (Tamiflu) and
zanamivir (Relenza)]; hepatitis (interferon),
herpes (Acyclovir), and AIDS
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Antiparasitic Agents
• A number of parasites, including
helminths (worms), can invade the
human body
• Worm infestation is always spread by a
feces-to-mouth route.
– Good hygiene is the best preventive.
– Some geographic areas are more prone.
– Various drugs treat different infestations.
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Adverse Drug Reactions
and Drug Allergies
• Therapy
– Discontinue the drug!
– The symptoms usually resolve within 2
weeks.
– Administer the following to reduce
symptoms:
• Antihistamine agents
• Corticosteroid agents
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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Criteria for Drug
Hypersensitivity Reactions
• Symptoms consistent with drug reaction
• Drug known to cause such symptoms
• Timing of appearance of symptoms
consistent with drug reaction
• Other causes of symptoms ruled out
Elsevier items and derived items © 2009 by Saunders, an imprint of Elsevier Inc. Some material was previously published.
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