Your poor friend. I am on baby no 2 and have suffered both times round so can empathise a bit with her.
A good website for self help tips is [www.hyperemesis.or.uk]], it really helped me. Everybody finds different things work for them but there is a long list of things to try on that site.
1 Cold drinks
For me it was also ice cold liquid, and although it didn't "cure" me, it did keep me hydrated enough to stop me being rehospitalised for the 6th time this pregnancy at xmas. Had been on a drip almost constantly etc etc for the previous 8 weeks. Ice cold water, lots of ice cubes, and a dash of high juice squash to stop my blood sugar levels plummetting.
2 Separate tiny portions
Would second the not eating and dinking together bit, as well as eating only tiny tiny amounts of very bland foods (eg a piece of buttered toast, then a couple of hours later half a plain jacket potato, couple of hours later something else).
3 Being firm with drs
And if the medication you are being given doesn't work- speak up. Either the method or the drug itself. Eg gp gave me tablets to take orally to begin with but of course I couldn't even keep down my own saliva let alone a sip of water to take the pill with. Ditto syrup. Suppositories or meltlets only for me - meltlets are little "pills" that you put between your gum and cheek and they dissolve there.
The stemetil, cyclizine, and a couple of others I can't remember that I was prescribed in hospital did not do a jot to help (although the cyclizine did make me feel lovely and drunk and gave me incredible psychadelic electrically sparky dreams and tingles which was a welcome distraction!). They eventually gave me a shot of Ondansetron (brand name Zofran) which was brilliant- it stopped the sickness quite quickly, although as it is very expensive it is always given as a last resort. So I'd have to go through a few days of them trying the others each time I was admitted before they'd see that it wasn't working and give me the Zofran. Last couple of times I just said "look I know the drill this is what happened the last 3 times..." and they'd give it me straight away. So make sure your friend (or someone who can advocate or talk for her if she is throwing up too often/too out of it to speak herself)knows she can speak up and ask them about trying something else.
4 Sweets
I'm now 27 weeks and just about to go back to work as the vomiting is almost completely gone. What stops me throwing up now is a combination of the methods above and chewing gum constantly. For a good 6 weeks though it wasn't sugar free gum it was Murray Mints and I must have got through nearly a packet a day. As long as I had a mint on the go I wasn't sick! Weird but desperate times call for desparate measures and all that!
Sorry this is such an essay- but would do anything to try and stop someone getting so ill and depressed as I was!
Really good luck for your friend, she's lucky to have a fiend like you, you sound v supportive and nice! Tell her to take it easy- stress can make the sickness worse so not to try to return to "normal" too soon, sleep as much as she can (not easy I know with another one to look after already) and good luck for the rest of her pg. x