Perscription Drug Instructions

[MC$E]

My son went to the Doctor today for ear pain, it turns out he has an ear infection. I took his perscription to get filled, and was reading the Rx Advisor insert the pharmacy placed in the bag. The drug is Zithromax 200MG/5ML.

Under the heading "How to use this medicine" it says (in part):

"In the US, this medicine may be taken on an empty stomach or with food. In Canada, take this medicine on an empty stomach at least 1 hour before or 2 hours after eating. "


WTF, are Canadians different biologically? Are there two different formulations of the drug? Any ideas?

My best guess is that they were tested differently, but that doesn't make a whole lot of sense to me.



MC$E

[Modoc]

It all has to do with the FDA and "approved" drug trials. My guess is that the studies were done one way (empty stomach) by the Canadians and that the US studies did both. Pretty silly, huh?

But besides that, most ear infections are viral and don't need antibiotics!

[mnemosyne]

The FDA and the Canadian equivalent (which I forget the initials for) have different standards, although for the most part they both follow what is known as the Unites States Pharmacoepia for the basics. It is possible that when the Canadian agency reviewed the data (possibly a good 2 years after the FDA did), it found a slightly better performance on a more empty stomach than on a full one. Also, depending on the time it takes to become active in the body, the general specification of "with food" might lead people to take it at the same time, although by the time it becomes active, you've digested a significant amount of food. Lots of possible reasons, but essentially it comes down to different standards. Canada tends to be more stringent than the USA when it comes to most drugs (I believe).