Doxy:
Kills staff
Kills strep
Kills MRSA
Treats pneumonia (CAP, anyway)
Kills chlamydia
Can be used for UTIs in young sexually active females.
Cheap as dirt
What's not to like?
So I definitely agree with a lot of this. But when doxycycline is less effective than azithromycin and a treatment failure costs a lot more money (return visit) and morbidity, I'm more hesitant.
When deciding between 14 pills (7 days BID) of doxycycline to treat chlamydia, or a single dose of azithromycin with guaranteed cure (which you could even do in the ED before they left if compliance were a serious issue), in a patient population that may have difficulty filling a prescription or adhering to a BID regimen for a week... it seems that it would be difficult to choose doxycycline. Although since county here just essentially gives the medications to patients anyway if they are unable to pay (some paperwork involved from what I understand, but patients end up getting their meds), I guess that would be a much different story if they had to pay a significant difference out of pocket, but that might be an argument for just dosing the one dose of azithromycin in the ED before they leave and calling it a day (in a copay-based system or a flat fee per visit situation).
Resistance to pneumococcus with doxycycline is not unheard of (20% in most studies, but your local institutional susceptibilities will of course be a better judge as in ccfccp's experience), and again, when deciding between a cheap drug with a higher risk of treatment failure or a more expensive drug with a lower risk of treatment failure, it's more difficult to justify to me even from an economical standpoint. There's some newer evidence that because of the ridiculously long halflife of azithromycin you may be able to give a 2g microsphere single dose in the ED and not have them take anything as an outpatient, but I don't know much about the cost or availability of that treatment.
For UTIs in sexually active females, you'd be treating for Staphylococcus saprophyticus, but that isn't the most common cause of UTI in that patient population, either (obviously still E. coli, which isn't covered as well). I feel that again even in that patient population, in the absence of other data, I'd choose what's empirically going to be the most effective. And since S. saprophyticus isn't a nitrate reducer, if the dip had nitrites that'd rule out S. saprophyticus anyway.
But I 100% agree with everything else. If I'm missing something (and I probably am -- not even an M.D. yet, so obviously can't even independently write a prescription
) with the above statements, I'd like to learn.
