Most people can not believe that a dog can suffer from a lack of appetite. However, it is fairly common. A lack of appetite can be the result of picky eating, a lack of exercise, and stress. There are several things that you can do that will act as an appetite stimulant for dogs. If these things do not work and the issue persists then I would recommend seeking help from the vet immediately.
Response to an event
Some dogs may lose their appetite as a reaction to a particular change or an event. Activites such as traveling in a car or airplane, or having a new pet or person in the house may cause your dog to lose interest in eating. Although it is no appetite stimulant for dogs, just making sure you feed your dog at times when these situations are not happening may be the solution to the problem altogether.
Just like us humans, dogs burn calories when they get exercise. The more exercise they get the more calories they burn. The only way to replace these calories is to eat. Thus the dog's appetite will naturally increase. I know, you must think I am a Harvard Professor, but this simple remedy can really make a huge difference. Exercise is one of the most effective appetite stimulants for dogs out there.
There are several herbal supplements that can be used to stimulate your dog's appetite. An an an an ingredient such as dandelion and b vitamins can be an effective appetite stimulant for dogs. These supplements can be mixed with food. One herbal supplement, in particular, is CBD Oil, and it works incredibly well as an appetite stimulant for dogs. CBD is extracted from the marijuana plant. Although it does not get your pet high or intoxicated, it still has the same appetite-stimulating effect.