Brief Answer:
few things to consider..

Detailed Answer:
Hello XXXXXXX Welcome back to HCM,
I've gone through your query and understand your concern,

Now at first, the reason behind the hiccup needs to be narrowed down, so try to find out what is it which may be causing it/ worsens it/ even improves it (it can be simple day to day life things, eg. eating too much food too quickly, drinking too much fluids, swallowing too much air, a sudden change in stomach temperature, such as drinking a hot beverage and then a cold beverage, smoking/alcohol etc.)..

If any of the above is found, then simply avoid it and it should improve within a matter of time only..

If not, then next time you get it, try the-

- Valsalva manoeuvre (perhaps check out a tutorial video in Youtube and practice few times beforehand), breath holding, hyperventilation or breathing into a paper bag, inducing even sneezing.

- Leaning forward to compress the chest or pulling the knees up to the chest.

- chew up some ice cubes, and/ mint leaves at that time.. do not drink excessive water, it won't help and in fact can even precipitate it even more..

- avoid stressful situations and dehydration (remain well hydrated through out the day by drinking lot of water, ~ 2.5 ltr per day, but not excessive amount all of a sudden, also avoid too many tea /coffee)..

- mental distraction, which will not only help taking your mind off it but also will be beneficial in reducing it..

If despite following all these, there's no relief then you should get a few simple screening investigations such as: CBC, U&Es, Serum calcium, Blood glucose, LFTs, Amylase, CXR and a 12 lead ECG to look in to it further..

There are few medications available but before trying any of them, I'd suggest you to follow all these as already advised which'll also help to detect the most probable cause/trigger factor behind this..

Do let me know how you stay in the due course..

Take Care
Kind Regards

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