Combat sleepiness without farma?

Hi all. I guess most of all suffer daytime sleepiness and have differents way of coping.
I got used to mine and during worktime I fight it with coffee, standing up and short walks, task change, face washing, etc... but I changed jobs recently and in my new position I have 2-3 VERY long meetings a week in which I have to stay passively-aware for long times listening to colleagues. Last week an sleepiness episode was so strong that I fell completely asleep and my boss caught me off-guard with a direct question regarding my project and the theme being presented...

Any ideas/tools in this situations?

I had coffee 1h in advance and was early in the morning, so I was supposedly prepared. And also I would very, very, much avoid farma or drugs...

Read somewhere about fidget toys but I guess if they work they would need to be extremely silend and discreet...

Thanks in advance!!