Dogs highly enjoy going through the trash and this can lead to the dog vomiting. Another cause is thattend to choke on their and this is actually the most frequent cause of vomiting. Another reason they throw up, believe it or not, is because they get carsick and this can cause the dog to become sick to the stomach and throw up; to avoid this, don't take the dog out in the car right after he has eaten, give his stomach some time to settle.You will be able to notice when the dog is going to throw up because usually start drooling more than normal, start licking their mouth and or swallow their saliva insistently. The best thing to do obviously is to keep a constant eye on what your dog eats and, if the dog does happen to throw up, check what he has vomited to try to identify what it is. If your dog throws up and you notice that it is just his normal , most likely your dog just gobbled his up too quickly, keep in mind though that this behavior usually occurs in that are stressed out or feel insecure. If this is your dog's case you can help him out by serving him smaller portions of or by changing his little by little. Whenever a dog "throws up" that has not yet been digested, he is not actually vomiting; he is just regurgitating his .