Hiccups are little more than a reflex, like the way your knee jerks when a doctor taps it with a hammer. They result when the vagus nerve or one of its branches, which runs from the brain to the abdomen, is irritated. And the vagus lets you know by tweaking the phrenic nerve, which leads to the diaphragm, the muscle below the lungs that helps you breathe. The diaphragm then spasms, causing the “hic” sound true to the condition’s name.
Experts say hiccups are most often a reaction to common digestive disturbances. And luckily, they’re usually more a nuisance than anything else. But what about the times when we seem to hiccup for no apparent reason? No one knows for sure why these seemingly innocuous bouts occur.

REMEDIES….
Have a teaspoon of sugar and allow it to dissolve slowly in your mouth without chewing it. This remedy is especially for toddlers and children who are unable to follow detailed instructions on breathing pattern.
Mix one cup of yogurt with a teaspoon of salt, stir it thoroughly until the salt dissolves completely. Have the yogurt slowly, this will help stop your hiccups
 Cardamom/elachi powder is an effective remedy for hiccups. Boil 1 ½ cups of water and add a teaspoon of freshly ground cardamom powder in it. Allow the liquid to cool and then strain the liquid and drink. This remedy helps the muscles of the diaphragm to relax and this will stop your hiccups.
Peel a small piece of fresh ginger and chew on it slowly to get rid of your hiccups.
Take a teaspoonful of vinegar. Its sour taste could stop a hiccup in its tracks.

Have some peanut butter.
A classic hiccups remedy involves eating a big spoonful of peanut butter. In the process of chewing and getting it off your tongue and teeth, your swallowing and breathing patterns are interrupted. And hence, the hiccups will be history.
Enjoy a little honey.
Put 1 teaspoon of honey, stirred in warm water, on the back of your tongue, and swallow it. Like dill, honey could potentially tickle the vagus nerve to make the hiccups stop.
Brown bag them
Breathe slowly and deeply into a small paper bag. (Stop if you feel light-headed.) This increases the carbon dioxide level in the blood and makes the diaphragm contract more deeply to bring in more oxygen, which may stop the spasms.