Hiccups. A medical nightmare if chronic. Doctors treat them with anti-psychotics. I have a friend who cannot stop them. I want to help him but no home "remedy" has helped and he does not need antipsychotic drugs. Any ideas?

I watched a tv show as a child that tried lots of tricks and determined they all made you gulp oxygen and re-regulate your breathing. Since then I've always found long deep breaths to eventually work. Not sure on chronic hiccups though.