Welcome to Unicornandbows and Chivari. Unicornandbows Iam sorry you feel so bad. Every half hour vomitng is awful. At this rate, you will soon be dehydrated. Have you got kesostix to check and see? They are good for checking the early stages of dehydration and are available from any chemists and they will admit you for fluids with a measurment of 3+. Have you got headache, dry skin, dry mouth and very scanty, 'builders tea' type urine? Have they got you on anti sickness meds? A good anti acid can make all the differnce. Are sugary drinks like flat coke or the juice of tinned fruit any good?
Chivari I am glad they have put you on Stemitil. Diarylite sound s good, ifyou can stand it. Interestingly, most can't. Crisps are a favourite, I think because salty foods, like sweet ones, seem to be te most bearable to most. A lot of women find that really good. If not, don't hesitate to ask for other meds. As above, a good anti acid can really help too and it's a good idea that you have some kesostix from any chemists to check for the early stages of dehydration.
Some drinks and foods that might help both. Flat full sugar coke, ice lollies, sips of the juice of tinned fruit, Dr Pepper, Lucoazade, fizzy orange, soda water, orange squash, fizzy water, Elderflower water, ice cubes, orange juce (if not too acid), lemonade, Robinson's fruit drinks and sips of chocolate milkshake (maybe soya). For food of a sort, cuppa soup, Scotch pancakes, baked potatoes, nibbles of crisps and chips, slices of melon and mango and cheap ice cream. Some swear by biscuits.
Great advice by Foodylicious and Hotchocolate. 
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