Unisom & Vitamin B6

Has anyone tried taking Unisom and vitamin B6 for nausea?  My doctor said to take 25mg of B6 per day and 25mg of Unisom each night. I got the Unisom, but I cannot find a 25mg dose of b6 ANYWHERE!  Has this worked for you and what dosage do you take? If you take 25mg of B6, where do you find it?