Your post title mentions dex but your question mentions meth - which is it. In any case the answer is the same I think but I'm responding to dex specifically:
Absolutely not! The tablet is mostly dangerous filler that will clog your needle and fuck you up if you actually get any into you. Wheel filters, if you can get them, can help keep a lot of the filler out but they are less than perfect.
There are threads that discuss extraction of the dex from the pills and cleaning it to make it suitable for IV but they all say it's too much hassle for such little return
Plus 5 mg of dex IV would not be worth it to anyone even with zero tolerance. You'd need to process quite a few pills.