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Flashcards in Antibiotics Deck (17):

Inhibitors of Cell Wall Synthesis

- Penicillin: weaken cell wall and promote bacteria lysis and death
- Cephalosporins: those allergic to peniciilin may be allergic as well
- Vancomycin: also inhibits bacterial cell RNA synthesis
Distrupt Cell Membrane:
- Amphotericin B (antiviral agent): increase cell wall permability, causing leakage of intracellular material


interrupts Metabolic Reactions Inside Cell

- sulphonamides: inhibit folic acid synthesis
- trimethoprim


Disruption of Bacterial Protein Synthesis

Bactericidal: "lethal"
- aminoglycosides
Bacteriostatic: "nonlethal"
- Clindamycin, Erythromycin, Tetracyclin


Interfere with DNA Replication

- FQs, metronidazole, rifampin



- decreasing concentration of med at site of action
- alter the structure of target molecules
- produce med antagonist
- cause med inactivation
*more likely to occur if dose is too low, time between doses is too long, therapy stops too soon, or drug is used prophylactically


Antibacterial VS Antimicroorganism

- substances that can harm microbes
- any agent, natural or synthetic that has ability to kill or suppress microorganisms


Penicillins Nursing Implications

- take oral with a full glass of water 1 hour before or 2 hours after a meal
- can inactivate aminoglycosides
- most likely to cause allergic reactions
- side effects are: GI/behavioural with large dose or cardiac effects with electrolyte imbalance
- Piperacillin-tazobactam: resistant to beta-lactamase (more effective)
- MRSA: treated with vacomycin, Clindamycin, or linezolid



- cefazolin: is IV or IM only; common side effects are GI, ppseudomembranous colitis (C-Diff), nephrotoxicity
- Carbapenems (primaxin) is resistance to beta-lactamase (mor eeffective but not for MRSA treatment)


Other Cell Wall Inhibitors

- Vancomycin: only used in serious infections where other antibiotics have failed, due to serious toxicity side effects
- admin IV over at least hour and monitor for extravasation
- nephrotoxicity and ototoxicity and significant histamine release


Bacteriostatic Protein Synthesis Inhibitors

Tetracycline and doxycycline:
- used in unusual organisms
- peptic ulcer disease, acne, and chlamydia
- overuse leads to resistance
- dairy products and antacids interfere with absorption of tetracycline
- adverse effects: GI, photosensitivity, superinfection, heptotoxicity and renal toxicity
- AVOID in pregnancy and in children under 8 years (stained teeth)
- ideally take on empty stomach but take with food if GI upset



- Erythromycin: inhibits C-P450 metabolizing enyzmes therefore watch rug interactions and toxicities
- ideally give on an empty stomach but can cause GI upset even in IV (2hrs after a meal or snack)



- used as an alternative to penicillin for serious infections but only used by itself due to too many interactions and toicities iwth other antibioitics
- adverse effect: GI, pseudomembranous colitis and blood abnormalities


Bactericidial Inhibitors of Protein Synthesis: Aminoglycosides

- Gentamicin and tobramycin: narrow spectrum, distrupt protein synthesis leading to bacterial death
- for serious infection due to serious side effects of nephrotoxicity, ototoxicity and neurotocixity
- parenterally
- monitor peak and trough levels; monitor for tinnitus and hearing loss
- adverse effect: blood dyscrasias and neurological disorders



- suppress bacterial synthesis of DNA, RNA, and proteins in organisms that synthesize thei own folic acid (not dietary)
- bacteriostatic
- used for UTIs
- adverse effect: allergic reaction and renal damage



- broad spectrum bacteriostatic (low) and bactericidal (high dose) that only work in the urine for UTI by damaging bacteri DNA
- adverse effect: GI disturbance (take with food or milk), pulmonary reactions, hematologic effects, peripheral neuropathy, heptatoxicity, birth defects, and CNS disturbances (vertigo)



ciprofloxcin and levofloxacin:
- broad spectrum
- oral is fast as IV
- used for UTIs, STDs, resp., skin, GI, bone, joint, and skin infections as well as Anthrax
- avoid milk, antacids, iron, and zinc supplements
- in older adults: risk of blurred vision, confusion, somnolence, and psychosis may exist



unique in that this agent is also an antifungal and antiprotozoal agent
- interacts with DNA to cause strand breakage and loss of helical structure= inhibition of nuleic acid synthesis= cell death
- treat anaerobic organisms, intra-ab and gynaecological.UT infections, and prophylaxis in abdominal surgeries
- edverse effects: N/V, diarrhea, headache, dry mouth, insomnia, vertigo, unpleasent metallic taste and discoloratin of urine (dark)
- take with food, avoid alcohol (metabolite accumulation)