Be aware of what you're getting. My ex wife was a Pharmacist until she went back to get her Master's with the goal of getting a Doctorate in Clinical Phamacology. As of 6 years ago, she was researching this very thing, but much may have changed.
From wiki:
The U.S. Food and Drug Administration (FDA) requires generics to be identical to or within an acceptable bioequivalent range of their brand-name counterparts, with respect to pharmacokinetic and pharmacodynamic properties.[3] (The FDA's use of the word "identical" is a legal interpretation, not literal.)
This has been a thing in the US for a while. Generic drugs can be the exact same thing as the brand, or they can be bioequivalent... meaning they have the same pharmakinetic result in the body. What this means is that comparing something like Zoloft to its generic Sertraline is like comparing Jack Daniels to Evan Williams. They are both whiskey with 40% ABV, so 4 shots of either one will get you equally drunk, but we all have that one friend who says that Evan Williams gives them a headache or a worse hangover. Even though the active ingredient in that case is identical, the other stuff with it might make other effects different.
In some cases, though, the generic doesn't have to be the exact compound as the brand as long as it has proven clinically to cause the "identical" result. As wiki noted above, it doesn't have to actually be identical in the literal sense, it has to have proven itself effective in the same trends of chemical result. If you give Zoloft to 1000 people in a clinical trial, and Sertraline to 1000 people in a trial, and both test groups showed an average of 40% improved selected serotonin re-uptake inhibition, you can call it Sertraline even if the compound is different.
I said all of that to say this: India and Mexico don't adhere to those rules. If you use a prescription to get medication from any other country, legally it is supposed to conform to US rules. If they are allowed to sell Acetominophen as Ibuprofen over there and you ask for Ibuprofen... they're supposed to not send you Acetominophen labeled as Ibuprofen. Legal there, not cool here. Where things get hazy is, how many Indian and Mexican pharmacies know US law, and even if they do... do they care?
If you don't use a prescription to get foreign drugs, they aren't bound by those rules.
So, what I'm saying is... buying the brand here in the US is a slam dunk, but expensive. Buying with a script from Mexico or India is a crap shoot. You might be getting the brand, the generic, or whatever bioequivalency laws they conform with in India or Mexico. Buying with a script from Canada is also a slam dunk. I would try to source the brand in this order of comfort: Canada, India, then Mexico as a last resort.