Expert: Barbara Judge - 6/17/2004

Question
Hello.  Today I was given SMZ/TMP 800-160 the generic for Bactrim DS for a sinus infection.
I took one then read somethings about it that scared me.
I have decided not to take anymore, but am still a little worried about the one that I did take.
I have two questions really.  The first being at what point can I say the pill is out of my system and I don't have to worry about a reaction and the other is, I called my Dr. and asked that I be given Amoxicilan instead (I have taken this before)  I only got voice mail and no one returned my call, it will be tommorow now before they do.  What I am wondering is, can I start the amoxicilan after taking one of the other one?
Thanks.

Answer
   In patients with normal kidney function the amount of generic Bactrim DS in your bloodstream should not be measurable after 40 to 50 hours.  In patients with impaired kidney function this time will be longer depending on the degree of renal impairment.  If your doctor decides that amoxicillin is appropriate therapy for you it should be OK  for you to start taking the amoxicillin when you receive the prescription.  There have not been significant documented drug interactions between generic Bactrim DS and amoxicillin.

Thanks

Barb Judge