Pigs foam and froth at the mouth for different reasons

My Pig Is Foaming and Frothing at the Mouth: 6 Reasons Why

My children are responsible for our little pig Gus’ upkeep, and they take this very seriously. 

Gus lives indoors and can move from the house into the garden throughout the day. A week ago, my daughter came tearing through the kitchen, screaming that Gus was having a fit.

I stopped what I was doing and panicked when I saw Gus foaming at the mouth. So many things ran through my head, from rabies to food poisoning. I phoned the vet immediately and described his symptoms.

Gus’ tail was also flicking from side to side, and he seemed on edge. The vet came out to the homestead to check out little Gus and run some tests.

Why is my pig frothing and foaming at the mouth? Pigs foam and froth at the mouth for different reasons, such as being in heat or stressed out. Parasites such as the pork tapeworm cause frothing and foaming at the mouth. Conditions such as foot-and-mouth disease and swine vesicular disease are more worrisome reasons.

6 Reasons Pigs Foam and Froth at the Mouth: Helpful Solutions

Generally, when a pig is healthy, they have a normal wet mouth with a relaxed tongue. You’ll notice the difference immediately if your pig starts foaming at the mouth. There will be lots of chomping and tongue movement as the saliva builds up to form the foam.

 Let’s take a look at five reasons that cause pigs to foam and froth at the mouth:

1. Pork Tapeworm (Taenia Solium)

A nasty and scary symptom of a tapeworm infestation in pigs is seizures. During a seizure your pig will convulse while chewing and chomping and begin foaming at the mouth. Taenia Solium, also known as the armed tapeworm, is a common (and troublesome) parasite that affects pigs who live close together in a pen.

The pork tapeworm parasite spreads when your pig unknowingly ingests the eggs through contaminated food and pig droppings. The tapeworm then moves to the intestinal walls and anchors itself in your pig’s muscles and small bowel.

Did You Know: One adult tapeworm can live in the small bowel for years and produce up to 50,000 eggs during its lifecycle?

Symptoms of Pork Tapeworm Infestation

If your pig has a tapeworm infestation, they’ll present with these common symptoms:

  • Diarrhea and vomiting
  • Chomping and chewing excessively
  • Sudden loss of weight
  • Foaming at the mouth (or frothy saliva)
  • Hunched over in pain
  • Convulsions and loss of consciousness
  • Ear stiffening

Healthy pig have normal wet mouth and relaxed tongue

Helpful Solutions for Pork Tapeworm 

Here are a few helpful solutions for pork tapeworm infestation:

  1. A single dose of Praziquantel effectively eliminates adult parasites. Alternatively, Niclosamide (4 tablets) can also be administered one at a time to paralyze and kill the parasites.
  2. Give your pig some papaya (ensure you remove the seeds, as they can cause a blockage in the intestinal tract). Papaya contains loss of weight that kill intestinal worms.
  3. Feed your pig 2 to 3 cloves of raw garlic daily to prevent the tapeworm parasites from thriving. Garlic naturally has antifungal, antiseptic, and antibacterial properties.

2. Oestrus Cycle and Being “In Heat”

Another common reason sows and boars foam and froth at the mouth is when they’re in heat. The boar makes loud chomping sounds to stimulate the buildup of saliva. After a few minutes, the saliva creates a thick and quite sticky foam.

This foam contains pheromones and androstene steroids (a chemical produced in the testicles and concentrated in the salivary glands) which attract the sow. You’ll notice the foam has an almost tangy smell and smells different from the standard foam that’s formed when anticipating food, for example.

A sow will also foam at the mouth when she is in heat, although the amount of foaming is nothing like the boar.

Symptoms of a Pig in Heat

Your pig will display the following symptoms if they’re in heat:

  • Loud chomping and grunting
  • Frothing and foaming at the mouth
  • The sow has a “standing reflex” – ears erect and back arched 
  • The sows vulva will swell and turn red

Helpful Solutions for Foaming from Pigs Being in Heat

Here are a few helpful solutions for when your pig is in heat and foaming:

  1. Ensure only one boar is servicing the sows in a pen. This avoids aggression and injury among the pigs.
  2. If you don’t want the pigs to mate, separate them until the sow’s heat cycle is over (two2 to three days).
  3. If your pigs are frustrated, try distracting them by throwing some hay into their pen.They’ll rummage around in the hay and forget about their frustration.
  4. Consider sterilizing your pigs if you don’t plan on using them for breeding. It can stop the development of smelly foam.

Pigs drool when experiencing heat stress

3. Pig’s Foot-and-Mouth Disease (FMD)

Foot-and-mouth disease is another common and contagious infection that affects pigs of all ages (piglets are known to suffer from cardiac arrest as a result). This virus  can cause this notifiable disease as it spreads rapidly through aerosols, infected drinking water, and direct contact

One of the most apparent signs of FMD is when your pig foams at the mouth. The continuous chomping and increase in saliva may cause this. It could also appear as sores or ulcers in their mouths and spreads to other body parts, such as their feet and udders.

Symptoms of Foot-and Mouth-Disease

Pig foot-and-mouth disease presents with the following symptoms:

  • Severe lameness and lack of energy
  • Formation of lesions on the tongue, lips, snout, udders (lactating sow), and feet
  • Excessive and audible chomping of jaws that leads to foaming and frothing at the mouth
  • Squealing and grunting
  • Presence of pus where the ulcers have burst (usually after 24 hours)
  • Depression
  • Back arched in pain

How to Treat Pig’s Foot-and-Mouth Disease

Unfortunately, there is no successful treatment for FMD. Although, it’s recommended to cull the infected pigs to prevent the further spread of the disease. Here are a few helpful solutions for the disease:

  1. Try to keep up to date with vaccines. However, this can be costly as the vaccines are only effective for six months.
  2. It’s best to isolate the infected pigs for culling to avoid spreading the disease.
  3. Stay in contact with local farmers to receive updates if there are any outbreaks in your area.

4. Stressed-Out Pig

Pigs get stressed-out too, and just like any animals or humans, their stress is triggered by different factors such as:

  • Anticipation of their food
  • Intruding into their space when you aren’t welcome
  • Sudden loud noises or strange smells
  • Separating a pig from the herd or sows from their babies
  • When your pig is ill or in pain
  • Or they’re just having a bad day

Symptoms of a Stressed-Out Pig

Here are some tell-tale signs that your pig is stressed out:

  • Foaming or frothing at the mouth
  • Chomping their jaws
  • Flicking their tail from side to side
  • Grunting and deep breathing
  • The pig starts circling you as a warning

You must ensure your pig doesn’t have FMD

Helpful Solutions for a Stressed-Out Pig

Here are some helpful solutions to calm your pig:

  1. Speak to your pig in a gentle and calming way. Don’t try to approach your pig until they’ve completely calmed down.
  2. Play soft music in the background and avoid sudden movements.
  3. Try to stick to a daily routine, as pigs get stressed when their routine is disrupted.
  4. If you suspect that your pig is ill, it’s essential to seek veterinary assistance.
  5. Pay attention to your pigs’ stress triggers, and try to avoid those situations.

5. Swine Vesicular Disease (SVD)

Swine vesicular disease is spread through direct contact with an infected pig and eating or drinking contaminated water and food. This disease is often confused with foot-and-mouth disease. However, these two viral diseases aren’t the same. Unlike foot-in-mouth (FMD), swine vesicular disease is not life-threatening and does not have as much of a negative impact on the economy as FMD.

You must ensure your pig doesn’t have FMD, as the authorities will need to be notified. SVD is spread through direct contact with an infected pig and eating or drinking contaminated water and food.

Symptoms of Swine Vesicular Disease

If your pig has swine vesicular disease, they’ll present with the following symptoms:

  • Blisters seen around the mouth and legs
  • Mild fever
  • Loss of appetite
  • Frothing at the mouth
  • A dark line appears on the hooves

Helpful Solutions for Swine Vesicular Disease

There is no vaccine for SVD, but the disease’s symptoms only last for 2 to 3 weeks. Here are a few helpful solutions for the disease:

  1. Quarantine infected pigs for about three weeks to avoid spreading the disease.
  2. Open lesions can be cleaned with natural soda ash, honey, and millet flour (as mentioned under the foot-and-mouth section). This will avoid further infections or sepsis of the lesions.
Healthy pigs don't froth at the mount

6. Poor Dental Health

Another reason your pig may be frothing and foaming at the mouth is if they have poor dental health (bad teeth). Poor oral hygiene is common in pigs that are on high-sugar diets. Over time the sugar causes tooth decay and rotten teeth, which triggers increased salivation, foaming, and frothing at the mouth.

One of the first signs that your pig has bad teeth is halitosis (bad breath), and the smell can be overwhelming to owners.

Symptoms of Poor Dental Health

Your pig will present with the following symptoms if they have poor dental health:

  • Ulcers inside the mouth and on the gums
  • Foul-smelling breath
  • Increased salivation, which leads to drooling and foaming
  • Loose teeth
  • Rotten teeth

Helpful Solutions for Poor Dental Health

Here are a few helpful solutions for poor dental health:

  1. Your vet will sedate your pig and examine their mouth inside. If there are rotten teeth present, they’ll need to be extracted to avoid further infection.
  2. Ask your vet to perform a surgical cleaning to remove plaque buildup and treat inflamed gums.
  3. Discuss your pigs’ diet with your vet, and change it accordingly.
  4. Take your pig for regular check-ups at the vet, especially if you notice excessive foaming or drooling.

Pig Foaming and Frothing at the Mouth FAQs

Do Pigs Drool?

Pigs drool (which is normal), especially when they are stressed or experiencing heat stress. If your pig is drooling excessively, you should take them for a check-up at the vet.

Do Pigs Salivate?

Pigs do salivate, and they usually salivate in anticipation of food.

Is it Normal for Pigs to Foam at the Mouth?

Pigs foam at the mouth for various reasons, and many of them, such as waiting for food, are perfectly normal. However, if a pig foams at the mouth due to a reaction or from pain, it’s vital to seek veterinary attention.


Going back to my story about Gus, the vet took swabs from his mouth to rule out any diseases or viruses. Fortunately, all the tests came back negative. After quite a bit of questioning, it was evident that Gus was getting fed at random times during the day.

The children were taking their chores in turns and weren’t sticking to a routine. Poor Gus was okay with this initially, but after a while, he became stressed and anxious as he waited for his food.

To prevent this from happening again, I drew up a timetable and allocated the responsibilities between my children. Gus now eats his food on time, and we haven’t experienced another foaming or frothing incident. Read our handy guide for more on healthy fruit and vegetables to feed your pig. 

My Most Used Pig Supplies

This list contains affiliate products. Affiliate products do not cost more but helps to support BestFarmAnimals and our goal to provide farm animal owners with accurate and helpful information.

Purina Pig Chow will last well (or Mazuri is popular, but I haven’t tried it), and the stainless steel non-skid bowls that will help keep the mess down.

A pig blanket to keep her warm. This one also has bright colors and helps to provide rooting without the destruction.

Pig Harness for walking and handling your pig. There are a lot to choose from, but this one is pretty easy to use. If you want one that has a separate leash, this looks like a good one.

A large crate for keeping her safe in your house at night and when you leave the house. This is essential. You’ll also want a litterbox, and I like mine with a lid for nighttime. Pine shavings are best, and you may be able to find them in larger quantities locally.

When you have accidents, Odoban will help eliminate odors. When you are potty training, these floor pads work great for keeping your house clean while training her to go in certain places.

You’ll also want an outdoor house to keep her warm when she gets outside time, an essential part of her development.

Dewormer- Ivermectin is the primary dewormer I use, although I do rotate with a non-ivermect ingredient once so that the worms don’t get immune to it.