I Am Currently On Pexep Cr 50 Mg. My Doctor

I am currently on pexep cr 50 mg. My doctor has advised me to reduce it to 37.5 mg cr. But when i do i get lots of body imbalance. I heaed that it is advisable to reduce by 10 % only at a time. I did that by cutting pexep 10 mg into 4 pieces and taking only 3 pieces. But still i got withdrawal effects. What is the best way to avoid withdrawal effects esp. The giddyness, vertigo etc.