Pharm D students have not eligible for gpat because pharm D is pg level course. 

Only b pharmacy students have eligible for gpat exam because it is ug level course

No you are not eligible for the GPAT exam, to  apply for GPAT, you need a Bachelor’s degree holders in Pharmacy (4 years after 10+2, including lateral entry candidates) OR those who are in the final year of B. Pharmacy course are eligible to appear for the GPAT exam. You can check the criteria officially here .