I was struggling with hiccups for about 45 minutes. I was coincidentally was finishing a beer. For some reason it popped into my head that maybe the negative pressure would help with my hiccups. I finished the beer, put the bottle to my mouth and sucked out all the air I could. When I couldn't suck out any more air I held it until I needed a breath of fresh air. When I started breathing again my hiccups were gone. I had tried just holding my breath multiple times over the past 45 minutes and it didn't help...but the negative pressure did the trick. This is the first time I have tried this so give it a shot next time you have hiccups and let me know if it works.