You should have written in your question about duration when he started vomiting, his eating habits and other signs of illness that your dog is showing. If your dog throws up occasionally then no need to worry because dogs can have occasional vomiting. Only persistent vomiting in dogs needs vet visit. I am giving you few possible reasons of vomiting in your dog but final diagnosis will be made by your vet. Most common causes of vomiting in dogs are
- Intestinal parasites
- GI tract obstruction
- Changes in food
- Overeating
- Eating rapidly
- Exercise after eating
- Grass eating
- Eating of garbage
- Eating of spoiled food
- Stress
- Anxiety
- Middle ear infection
- Heat stroke
- Intestinal and gastric tumors
- Food allergies
- Liver and kidney diseases
- Adrenal gland disease