Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
16 Cards in this Set
- Front
- Back
|
What is the mechanism of action for Tetracyclines?
|
Inhibition of the 30S ribosomal subunit by preventing binding of aatRNA
Bacteriostatic |
|
|
Mechanism of resistance to tetracyclines
|
Efflux: main mechanism
Decreased penetration (active transport is required for entry) Competitive binding to ribosome by cellular proteins |
|
|
What are unique properties of Tigecycline
|
Binds more strongly to 30S subunit
Not able to be pumped out as easily The super tetracycline! |
|
|
What is the absorption of Tetracyclines? What can complicate this?
|
Orally absorbed
Di and tri valent cations chelate - don't have it with milk! |
|
|
Tetracycline Distribution
|
Vd > body water; sequestered in boty
Doesn't penetrate CSF |
|
|
Tetracycline Metabolism
|
Concentrated in liver
T1/2 = 6 - 16 hr. |
|
|
Tetracycline excretion
|
mostly excreted renally
some excreted hepatically |
|
|
Tigecycline absorption
|
IV only
|
|
|
Tigecycline distribution
|
Well distributed
Greater Vd than water Most concentrated in respiratory tissues |
|
|
Tigecycline metabolism
|
Some in liver (<10%)
T1/2 > 27 hr |
|
|
Tigecycline excretion
|
Bile - 60%
Renal - 30% Hepatic - 10% |
|
|
Who shouldn't you prescribe tetracyclines to? Why?
|
Pregnant women, young children
Tetracyclines chelate to calcium. Effect bone growth, stain teeth |
|
|
Adverse effects of tetracyclines
|
Large dose hepatotoxicity
If expired, nephrotoxicity Photosensitivity Failure of oral contraceptives (use barrier contraceptives for 2 weeks after) Staining of teeth |
|
|
Tetracycline clinical uses
|
Intracellular bugs!
Rickettsia Chlamydia Mycroplasma pneumoniae Acne (topically) |
|
|
Tigecycline clinical uses
|
Complicated skin, intra-abdominal infections
Drug resistant organisms |
|
|
Tigecycline adverse effects
|
GI nausea, vomiting, diarrhea
|
