My name is***** and I am sorry to hear that your dog is vomiting this evening.
There are many causes of vomiting in dogs. The most common is eating something they shouldn't, like plants, trash, bugs, etc. They can also eat something that can cause a blockage of the intestines such as socks, sticks, rocks, etc. Other causes include pancreatitis, liver and kidney problems.
For tonight, the first thing is to take away the water. Dogs will drink after vomiting and this will irritate their stomach even more, causing more vomiting.
After the vomiting stops, wait four hours, and then you can offer small amounts (1/2 cup) of water once every 30 minutes for the rest of the evening. If there is no vomiting by morning you can offer bland food such as chicken and rice.
If she vomits any more tonight after removing the water, has bloody diarrhea or if she is weak and collapses she will need to go to the local animal emergency room.
Best regards, ***** ***** this answer helps you.
Feel free to contact me if you have any more questions.
Kansas State University,
College of Veterinary Medicine Class of 2001