Good. Hope you feel better soon.
That site does do syringe filters, under the name 'sterifilt', basically a plug-on attachment for normal luer-slip rigs, that is used to draw a solution through an 0.2 micron filter mesh, thereby both removing solid crap, and sterilizing it in the process. At least, of any normal bacteria. They can't screen out viruses such as HIV, hepatitis viruses and the like, but one would have to be irresponsible, and or stupid to contract them using somebody else's used works.
Really, it beggars belief sometimes to me that junkies share needles. They are so cheap, a few pence a rig, a needle and a clean, fresh micron filter. If a skaghead has enough money for gear, then they have enough for a new rig, new needle, new micron filter, and an amp of sterile water.
I'm no junky, and I certainly would never ever share works with somebody either, even if I was. But since its usually pills (oxy) that I shoot, using a micron filter first is an absolute MUST. I prefilter through a cigarette cotton, then filter that solution through the micron filters, and it works fantastic.
Turns a cloudy pill solution into something particulate-free and sterile.
For the rehydration salts though, unless its a true emergency,take them orally.
Uggh. throwing up sucks. I really, REALLY hate it. I can cope with the shits no problem, as unpleasant as a case of the rabid squits might be, but throwing up is much worse.