What Supplements Along With Sub Lingual Lozenge Should Be Given To A Person With Fatigue?

A friend of mine suffers from mid-afternoon fatigue at his desk on weekdays. I want to recommend a B 12 sub lingual lozenge and am wondering what is a good drink or snack for him to take it with...... he has it on a fairly regular basis. He is not depressed and enjoys his work but has a long commute and a special needs son....and not a lot of free time. Thank you.