Most causes of a dog foaming at the mouth are not concerning. Consider what your dog has been doing, his current body language and attitude, and if he has any signs of injury or illness to discover the cause.
Often a dog foaming at the mouth happens simply because they are excited, stressed, or have been exercising heavily. But if your dog seems unwell, it could be something more serious.
Aerated Drool
Dog saliva is usually flat, but panting can add little air bubbles to the drool. This is what causes the appearance of foam! Air can get into your dog’s drool for many different reasons:
- Panting or breathing rapidly from excitement
- Sniffing heavily while also drooling (especially for male dogs sniffing a female dog’s urine)
- Panting due to stress or anxiety
- Panting heavily after exercising or playing hard
- Ate something that tasted bad
If your dog is foaming at the mouth but acting normally, one of these causes is often the reason.
Nausea
If your dog feels a bit pukey, he will likely drool more than usual. This drool can become aerated with tiny bubbles, making it look like foam.
Young dogs frequently experience car sickness, and will be nauseous, drooly, and foam at the mouth when riding in the car. Thankfully most puppies grow out of this. To help your dog, try different methods of riding in the car: crate versus harness with seatbelt, able to see out the windows versus covered to block the view. Your veterinarian can prescribe meds for persistent or severe motion sickness in dogs.
Health Causes of Dog Foaming at Mouth
Several health conditions can cause excessive drooling and resultant foaming at the mouth. Dogs with an underlying issue causing the foaming will likely have additional symptoms.
- Heat stress or heat stroke
- Nausea from a viral, bacterial, or metabolic illness
- Dental disease and pain in the mouth
- Object stuck in the mouth
- Consumed a toxic substance
- Bloat
- Rabies
Heat stress can occur when a dog overheats, usually from being too active in hot conditions or not having adequate ventilation and water availability. If you suspect heat stress in your dog, move him to shade, apply water to his head, underside, and paws, and seek veterinary care immediately.
Many infections and illnesses can cause nausea. Exact symptoms will vary, but can include poor appetite, vomiting, diarrhea, lethargy, and weight loss. Schedule a vet appointment to get a diagnosis.
Dogs with dental disease often drool to try to soothe his mouth. Antibiotics can help, but the best solution is often a dental cleaning under anesthesia to get the teeth and mouth fully cleaned up.
If something is stuck in your dog’s mouth, he may paw at or rub his face and may gag. Gently remove the item if your dog will let you, but some dogs may require sedation to free a stuck object.
Many toxins cause nausea. If you know or suspect your dog has consumed a toxic substance, call a pet poison hotline immediately to find out the best course of action.
A word on toads: many toads cause dogs to foam at the mouth if the dog licks them. Know what toads are in your area, and if they are generally safe or can be toxic. Rinsing your dog’s mouth with water is often helpful.
Bloat is when the dog’s stomach swells and fills with air, possibly also twisting and cutting off blood supply. This is an emergency that may require surgery.
Rabies virus is a worldwide problem and is fatal. This is why rabies vaccination is so important to keep you and your pets safe. If your dog is up to date on his rabies vaccination, it is extremely unlikely that his foamy mouth is due to rabies infection.
