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  #1  
Old 04-24-2011
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Bacteria What antibiotic for Gram Positive Bacteria?

Gram positive infection! say staph. What is the most appropriate antibiotics?? which one u will answer?
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Old 04-24-2011
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Flucloxacillin!
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Old 04-24-2011
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Originally Posted by 1TA2B View Post
Flucloxacillin!
why straight to fluoroquinolones?

id say amoxicillin first, if not methicillin or vancomycin.
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Old 04-24-2011
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why Flucloxa and not nafcillin or vanco?
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Old 04-24-2011
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flucloxacillin used for gram positive beta lactamase producers.

Amox...resistance...

Else u may use 1st gen cephalosporin bt 1st choice is fluclox

If allergic and unfection is mild, use macrolides or new quinolones
If allergic and infection is severe, use vanco

If resistant to vanco, use........?
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Old 04-24-2011
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Flucloxacillin (INN) or floxacillin (USAN) is a narrow-spectrum beta-lactam antibiotic of the penicillin class....
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Old 04-25-2011
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1st choice- nafcillin/oxacillin, IF RESISTANT e.g MRSA then vancomycin
if still resistant e.g VRSA/VISA quinupristan/dalfopristin
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Old 04-25-2011
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Yep! thats it.
If resistant to vanco, then linezolid or quinupristin/dalfopristin
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Old 04-25-2011
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Quote:
Originally Posted by Drshaharyarkhan View Post
1st choice- nafcillin/oxacillin, IF RESISTANT e.g MRSA then vancomycin
if still resistant e.g VRSA/VISA quinupristan/dalfopristin
that was my question too....why flucloxacillin and not nafcillin or oxacillin or even vancomycin?
isnt it slightly narrower spectrum than the 1st 2?
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Old 04-25-2011
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Quote:
Originally Posted by Oodesh View Post
Gram positive infection! say staph. What is the most appropriate antibiotics?? which one u will answer?
first choice will be the methicillin group- nafcillin, cloxacillin, dicloxacillin.... ampicillin, amoxicillin or piperacillin cover strep but they dnt cover staph... if we have to use them for staph, we have to add beta lactamase inhibitors... ampicillin+sulbactam or amoxicillin+clavulanate or piperacillin+tazobactam.... if patient has mild penicllin allergy, we can use 1st gen cephalosporins as cross reactivity is under 10%.... but if allergy is severe as anaphylaxis, shift to macrolides or clindamycin..... then for MRSA, use vancomycin or linezoild or tigecycline or daptomycin.....
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Old 04-25-2011
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Quote:
Originally Posted by neelmed View Post
first choice will be the methicillin group- nafcillin, cloxacillin, dicloxacillin.... ampicillin, amoxicillin or piperacillin cover strep but they dnt cover staph... if we have to use them for staph, we have to add beta lactamase inhibitors... ampicillin+sulbactam or amoxicillin+clavulanate or piperacillin+tazobactam.... if patient has mild penicllin allergy, we can use 1st gen cephalosporins as cross reactivity is under 10%.... but if allergy is severe as anaphylaxis, shift to macrolides or clindamycin..... then for MRSA, use vancomycin or linezoild or tigecycline or daptomycin.....

thats exactly my answer too
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Old 04-25-2011
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They don't use "flucloxacillin" in the US, the equivalent is actually DIcloxacillin. Either way, I guess it would be ox/clox/diclox/naf that would be the answer.
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Old 04-25-2011
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Quote:
Originally Posted by karansaraf View Post
They don't use "flucloxacillin" in the US, the equivalent is actually DIcloxacillin. Either way, I guess it would be ox/clox/diclox/naf that would be the answer.

Yes. Flucloxacillin - the first choice for Staphylococcus in the UK.

Thanks for your updates!
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Old 04-26-2011
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Flucoxacillin, dicloxacillin, and cloxacillin all belong to the class of penicillinase-resistant penicillins (along with oxacillin and nafcillin).
Unlike other classes of penicillins, antibiotics within this particular class are very similar in terms of spectrum of activity and offer no clinical comparative advantage over one another in terms of spectrum.

All the penicillinase-resistant penicillins are active against gram-positive bacteria, specifically Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus milleri, and Streptococcus Groups A, B, C, and G as well as the peptostreptococcus anaerobe.

They are marginally active against Viridans streptococcus and Staph. epidermidis, however, other antibiotics show much greater activity against these organisms.

in the US, only 3 (dicloxacillin, oxacillin, and nafcillin) of the 5 penicillinase-resistant penicillins are marketed and they are available in limited dosage forms. Dicloxacillin is only available in oral formulations, whereas nafcillin and oxacillin are only available as injectable formulations. Therefore, US formularies tend to list 2 different antibiotics in this class: dicloxacillin as the oral formulation and either nafcillin or oxacillin as the injectable formulation.
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Old 04-26-2011
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Quote:
Originally Posted by Seetal View Post
why straight to fluoroquinolones?

id say amoxicillin first, if not methicillin or vancomycin.
oh damn my bad... oxacins are fluoroquinolones not oxaCILLINs!!! y didnt anyone correct me?
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Old 04-26-2011
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I wrote tht its from the penicillin class. Dnt wry, we learn from our mistakes :-) cheers!!
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