1 GI Distress
One of the most common reasons that make a dog release white foam is Gastric Distress. GI Distress could also lead to vomiting, which can be caused due to ingesting a toxin, eating grass or another similar stomach irritant, heart stroke, bacterial infection, or eating anything sugary or spicy.
It is a life-threatening condition in which a dog's abdomen may appear distended. It is also known as gastric dilatation and is caused when the stomach fills in the air. Although it does put much pressure on other organs of the dog, it immensely affects the diaphragm, which could make it hard for them to breathe.
3 Kennel Cough
It is a highly contagious respiratory disease among dogs, also known as the canine infectious tracheobronchitis. It is mainly caused by Bordetella bacteria and generally remains from 3 to 10 days. Bloat can increase the possibility for the dog to suffer from vomiting, upset stomach, loud cough, and running nose.
4 Acid reflux
The dogs are very likely to experience acid reflux, just like humans do when gastrointestinal fluid flows into the esophagus.
5 Tracheal collapse
This situation could arise when the tracheal rings happen to be inside the dog's windpipe. This can even make the windpipe collapse, and your dog may develop a honking cough as well.
6 Fungal infections
Valley Fever is a fungal infection that is majorly found in the dogs living near or in deserts. It is caused by spores found in the soil, making the dog experiencing a stubborn cough. The coughing could result in the release of mucus.
7 Bilious Vomiting Syndrome (Vomiting Yellow Foam)
If a dog is undergoing this syndrome, they may not be able to sleep properly. They are likely to vomit and retch and leave a whitish or yellow foam. This yellow foam's major cause is the buildup of bile due to the stomach being empty for too long.
8 Food allergies
If a dog is allergic to a particular food, they may also release white foam while coughing up. Some breeds are allergic to certain types of food, and if they try to eat it, it can lead to indigestion. You can get to know this by changing your dog's diet if they stopped throwing up, then food was the only cause. Still, in case the problem persists, you need to consult your vet.
9 Kidney problem
Your dog may experience frothy vomit, pale gums, and abrupt thirst levels if their kidney is not functioning properly.
The damaged pancreas of the dog could also make them highly prone to cough up white foam.