Corine, you didn't say what your dog might have eaten while he was outside. Is he eating at all, or drinking? You need to make sure that he stays hydrated, since he is throwing up, he can die just from that alone. Have you not contacted a vet at all? Or are you not able to afford that luxury? Been there myself! If you have some vitamin C around the house, crush it up, melt it in a small amount of water, and make sure you get it down Fido's gullet. You also didn't say what size of dog you have, so any advice at all is going to be "iffy". Vitamin C is a good first response to practically anything that is going on with an animal, from snake bite to ...whatever. If it is a small doggie, then about 250 mgs in just enough water to melt it and make it available to be given in a dosing syringe should be good for a first dose. If it is a "larger" dog, one around 50 lbs then you need to get around a gram (1000 mgs) down him. You can add some baking soda to this, just a pinch, to buffer it, and they don't fight it so much. Oh, any animal for some reason just has a fit when Vitamin C is introduced, no matter how ill they are, so be prepared. Be sure you have a good syringe, and make sure the Vit C is completely melted. Good Luck. This should get you by until you can find out what else to do.