Metformin and Levoquin interaction

Yes, this is a medical question that I probably should have had my doctor dig up more details about, but I think it is kosher here because I have been taking Metformin for years and Levaquin numerous times during that period without ill-effect.

My doctor has mentioned a couple of times when I’ve had Levaquin prescriptions that it apparently can interact with Metformin, but he didn’t mention specific symptoms. Do the professionals in the audience happen to know what the interaction supposedly is? I tried googling and I can’t find any mention of the two interacting. has a good interactions checker - you plug in all your drugs and they point out any interactions. From there:

FWIW, I have a number of “moderate” interactions on medications I take, and have never had problems with them. It’s something to keep an eye on, however.

It has been my experience that pharmacists are generally MUCH more knowledgeable than physicians on the ins & outs of the medicines. Not always, of course…but it is right up their alley :slight_smile: Also, I assume that you read all the tiny print on the medication’s ‘info insert’ (if you were given such - if not, get it in writing, so to speak, from the pharma person). I forget what that piece of paper is called, but usually there is a VERY exhaustive list of known interactions and other tidbits that may help answer this for you. I am not speaking of the printout sometimes received that says typical “call Doc if any problems/take as directed/don’t drive if affecting you/etc”, but the one with technical product info that often requires a magnifying glass to read it all.

Levaquin-Metformin interactions


I believe this is a typical “CYA” type of statement. That is, another antibiotic, called gatifloxacin, was associated with deranged blood sugar levels (and was actually since taken off the market). Here is the relevant paper which led to gatifloxacin’s removal. Other than that bizarre and indirect “interaction”, there is none of which I am aware (and that includes searching a drug interaction site as well as a PubMed search)

Thanks! Like I said, I haven’t had any weird reactions from taking both together; I was just curious.

OMG, Mama Zappa, that’s awesome.

Note that gatifloxacin is still available for opthalamic use, under the brand name Zymar. I’ve used it a couple times in recent years, including as recently as a month ago.