There’s a common saying that you can’t die from holding your breath, because once you pass out, the autonomic nervous system takes over and you’ll start breathing again.
The inspiration for this question is this video of a guy who apparently almost died from holding his breath too long, and being told to breathe while he was blacked out is what saved his life. People in the comments are praising the rescuers for saving the guy’s life by slapping him and shouting at him to breathe after he passed out from holding his breath, and are acting like had the rescuers not yelled at him to breathe, he surely would’ve died.
It’s commonly done in some specific cases of people not breathing. Sleep apnea and opioid drug overdoses are two immediate examples I can think of.
With opioid drug overdoses, stimulation in general can be (temporarily) effective if they haven’t taken too much. Usually, they require more stimulation, such as sternal rubs or trapezius pinching, but I have seen cases where they needed someone to shout at them every 30 seconds or so.