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Simethicone

Brand names: Gas-X, Mylicon, Phazyme

Simethicone breaks up gas bubbles in the gut to ease bloating and gas pain.

Brand namesGas-X, Mylicon, Phazyme
Type of medicineAnti-gas medicine
Prescription?Over the counter
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

It isn't absorbed into the body.

What it's used for

  • Gas, bloating, and pressure
  • Gassy babies (infant drops)

How to take it

  • Take it after meals and at bedtime as needed, following the label.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Very few
Call your provider todayBelly pain with fever, vomiting, or blood in stool

Warnings

  • See a provider for gas or bloating with weight loss or that keeps coming back.

Other medicines, foods, and alcohol

  • It may lower levothyroxine absorption; separate them.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Generally considered safe. Ask your provider.

Missed doses, overdose, and storage

If you miss a dose

This medicine is often taken only when needed. If you take it on a schedule, take a missed dose when you remember, unless it's almost time for the next one. Don't double up.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.