How to stop or reduce graphite from reflecting light? Drawings drawn with graphite shine a lot under even a little light. The paper needs to be held at certain angle for proper viewing. Anyway to reduce or stop this?
Spray fixative should make the drawing more matte as well as protecting it. 

You could also try a layer of acrylic matte medium, sprayed or brushed, but that would be a little more involved and riskier to the original work if it cannot handle the wet medium. 

Either way do some test pieces before trying on the finished work. 

I also would recommend drawing with a softer lead for dark areas, it will require less working and less material to get the tone you want, which means less buildup and less gloss.