Quote from oldtime:
I was a long haul truck driver, so I know all about drowsiness, and I know every trick in the book. The only solution is sleep or to almost kill yourself driving off the road, that will wake you up!
Get checked out for sleep apnia. If you have it, when you are sleeping, you are not really sleeping. They have a machine you can sleep with at night (a face mask,) People who have it get very drowsy during the day.
none of the tricks work, not caffeine, not drugs, not snacks not driving with the window open, not walking around, but sometimes talking to somebody, especially a woman, will wake you up. We use to do on the cb, but I suppose now they do it on cell phone.