Pet Medication 101: Simethicone

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Pet Medication 101: Simethicone

It’s important to understand a medication’s uses and side effects before giving it to your pet. This medication info sheet is meant to give you a good understanding of what simethicone (Gas-X, Alka-Seltzer, etc.) is used for, how it works, and potential side effects in cats and dogs. Always consult a veterinarian before giving your pet any medication.

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1. Drug Name:


2. Brand Names:

Gas-X, Alka-Seltzer Anti-Gas, Equilizer Gas Relief, Genasyme, Maalox Anti-Gas, Mylanta Gas, Mylicon, Phazyme

3. How Dispensed:

Over the counter

4. Forms:

125mg, 180mg, 250mg capsules; 80mg and 125mg tablets; 80mg and 125mg chewable tablets; 20mg/0.3mL and 40mg/0.6mL oral liquid; 40mg and 62.5mg oral disintegrating strips

5. Drug Type/Class:

Gastrointestinal agent

6. Uses for Dogs and Cats:

Used to treat discomfort, pain, bloating, burping, and flatulence caused by excessive intestinal gas.

7. How it Works:

Simethicone acts in the stomach and intestines to change the surface tension of gas bubbles, enabling their breakdown and the formation of larger bubbles, which is thought to make gas easier to eliminate.

8. Side Effects and/or Signs of Overdose:

Diarrhea, nausea, vomiting, and lethargy

9. Drug Interactions:

Levothyroxine (thyroid medication)

10. Cautionary Statements:

  • Never give your dog simethicone without the approval of your veterinarian.
  • If your dog is showing signs of restlessness, abdominal enlargement, and nonproductive vomiting, please see your vet right away. These could be symptoms of a potentially life-threatening condition called Gastric Dilatation and Volvulus (GDV).
  • Simethicone has not been evaluated for safety during pregnancy or lactation and should be used with caution in either situation.

Read more:

Medication Info Sheet: Zantac

Medication Info Sheet: Tagamet

Medication Info Sheet: Imodium

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