B6 for nausea

Hi ladies! This is my second pregnancy and what they say is so true... No two pregnancies are alike! I'm so incredibly nauseous and sick this time around all I can manage to stomach is crackers! I've seen around that some women take a b6 supplement to combat this dreaded pregnancy symptom. My question is, I see that some recommended doses are low, approx. 25mg 3x a day. But all I could find is a 100mg pill. I would just call my doc, but of course it's the weekend. Have any of you had your doctor recommend b6, and if so what dose? I'm fearful the 100mg is too much in addition to what's in my prenatal.