Summary
Summary Pharmacology Antimicrobial drugs
- Module
- Pharmacology
- Institution
- Undefined
Structured notes for all healthcare professionals on Pharmacology. Includes all antimicrobial medications, mechanism of action, side effects etc.
[Show more]
Content preview
65. Antimicrobial drugs: mechanism of action, mechanism of resistance.CLASSIFICATION ACCORDING TO SPECTRUM OF ACTIVITY.
Depending on the range of bacterial species susceptible to these agents, antibacterials are
classified as broad-spectrum, extended-spectrum, or narrow- spectrum.
A. Narrow-spectrum antibiotics
Chemotherapeutic agents acting only on a single or a limited group of microorganisms are
said to have a narrow spectrum. For example, isoniazid is active only against
Mycobacterium tuberculosis.
B. Extended-spectrum antibiotics
Extended spectrum is the term applied to antibiotics that are modified to be effective
against gram-positive organisms and also against a significant number of gram-negative
bacteria. For example, ampicillin is considered to have an extended spectrum because it acts
against gram-positive and some gram-negative bacteria.
C. Broad-spectrum antibiotics
Drugs such as tetracycline, fluoroquinolones and carbapenems affect a wide variety of
microbial species and are referred to as broad-spectrum antibiotics. Administration of
broad-spectrum antibiotics can drastically alter the nature of the normal bacterial flora and
precipitate a super infection due to organisms such as Clostridium difficile, the growth of
which is normally kept in check by the presence of other colonizing microorganisms.
1. Bactericidal drugs are those that kill target organisms. Examples of bactericidal drugs
include aminoglycosides, cephalosporins, penicillins, and quinolones.
2. Bacteriostatic drugs inhibit or delay bacterial growth and replication. Examples of such
include tetracyclines, sulfonamides, and macrolides.
Some antibiotics can be both bacteriostatic and bactericidal, depending on the dose,
duration of exposure and the state of the invading bacteria. For example, aminoglycosides,
fluoroquinolones, and metronidazole exert concentration-dependent killing characteristics;
their rate of killing increases as the drug concentration increases.
1
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lilmiszangel. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £3.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
70055 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now