Gas-X (simethicone) is an over-the-counter medicine which can be used to relieve dogs of painful flatulence and wind, or as an aid during a bloat emergency. It works by combining small gas bubbles in the intestines into larger gas bubbles which can then be passed more easily from the body.

Contrary to popular belief, the medicine is not a cure for bloat, and may not even be very effective as an aid depending on the cause of the bloating. However, it may help to buy your dog some extra time and all owners should have the medicine in their cabinet for emergency situations. You can get cheap Gas-X and generic simethicone here.

Recommended Dosage

Warning: Speak to your vet before giving medicines to your dog. Also be aware that bloat is life threatening without professional veterinary attention and is the second biggest killer of dogs behind cancer. Do not attempt to treat the condition at home, always take your pet to the nearest animal emergency clinic.

Gas-X is available in regular strength, extra strength and ultra strength formulations. When treating dogs you should generally use the regular strength formula (each tablet contains 80 mg of simethicone) but the larger doses may be more suitable during an emergency. When not used to treat bloating the medicine is usually given at the following dosage:

Size of dog


Small20 mg
Medium40 mg
Large80 mg

In a bloat emergency, the best course of action is often to double the above dosage and immediately take your dog to the nearest animal hospital. For small and medium dogs the tablets are more suitable than the gelcaps as they can easily be split into halves and quarters.

How long will it take to work?

The effects of simethicone kick in very quickly, within minutes.

Example: A 10 lb dog could be given 20 mg or a quarter of a regular strength tablet.

Can I Give My Dog Gas-X?

Gas-X is very safe for dogs, it is not absorbed into the bloodstream and is usually well tolerated at unusually high doses. Up to 8000 mg has been given to dogs without causing side effects apart from a loose stool, which is why many choose a “better safe than sorry” approach to this medicine and give very large amounts whenever they think their dog is bloating.

Pregnancy: There is currently not much information about the safety of this medicine during pregnancy, but it does not cross the placenta and is likely to be safe. We recommend checking with your vet before giving simethicone to a pregnant pet.

Safety Recommendations

For safety we recommend you:

  • Always seek veterinary care if you suspect your dog is bloating
  • Always have a box of simethicone in your home for emergencies
  • Feed your dog when they are calm, rather than when they have been exercising hard
  • Feed smaller meals throughout the day instead of one large meal
  • Do not give too much water before or after meals

The best way to treat bloat is to make sure it never happens to begin with. Feeding your dog smaller meals through the day and feeding them when they are rested will greatly lower the risk of them developing this dangerous condition.

What Is It Used For?

Simethicone can be used to help relieve the discomfort and pressure associated with gas. It can also be used in an emergency during the beginning stages of bloat, but may be less effective or completely ineffective as the condition progresses, particularly if the stomach twists.

Side Effects

Simethicone is not likely to cause any side effects. If extremely large amounts are given your dog could experience loose stools.


Gas-X Website
Walker Valley Vet