DMAA and ephedrine to Mexico - customs

[memfaction]

I need to send 50 unbranded fatburner tabs which contain DMAA and EPH to Mexico from EU. I plan to send them in envelope or letter as small as possible and without any value (free content). Would that be a problem? Are customs in Mexico strict and would seize such letter? Could there be any other problems if they catch it?

Any advice would be really appreciated. Thanks!