What Are the Side Effects of Gas-X? Plus More FAQs About This Over-the-Counter Medication
Key takeaways:
Gas-X (simethicone) is an over-the-counter medication used to treat symptoms of gas such as fullness and bloating.
Gas-X isn’t absorbed into your bloodstream. So Gas-X side effects are minimal but may include mild diarrhea and nausea.
It’s possible to safely take Gas-X every day. But how long you should use it depends on which product you’re taking. In general, it’s best to contact a healthcare professional if you need Gas-X for more than 2 weeks.
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Table of contents
Gas-X (simethicone) is an over-the-counter (OTC) medication that can relieve uncomfortable symptoms of gas, like feelings of fullness or bloating. Typically, it’s taken as needed when symptoms appear. It comes in many different products and in many different forms, such as capsules, chewable tablets, and an oral liquid.
Gas-X side effects aren’t common. However, it can cause mild nausea or diarrhea for some people. We’ll cover these two Gas-X side effects here, along with other frequently asked questions about this medication.
1. Nausea
It’s possible to develop nausea after taking Gas-X. But there are several potential causes for nausea and vomiting. So it can be hard to tell if your nausea is due to Gas-X or something else.
First, pay attention to when your nausea started. If it started before you began taking Gas-X, there’s likely a different cause. If your nausea occurs soon after using Gas-X, then Gas-X may be to blame.
Nausea caused by medications may improve by taking your medications with food. You can also avoid eating foods that can make nausea worse, such as fried or fatty foods. These foods can also cause gas, so they’re best avoided even if you don’t have nausea.
If these tips don’t work, or your nausea doesn't improve within a few days, contact a healthcare professional. They can help determine if your nausea is from Gas-X or if there’s another possible cause. If at any point you have severe abdominal pain or large amounts of blood in your vomit, seek emergency care. These are signs that something more serious is going on.
2. Diarrhea
Diarrhea is another possible Gas-X side effect. If it happens, it’s typically mild.
In most cases, diarrhea should improve after you stop taking the medication. But if you’re experiencing diarrhea while taking Gas-X, it may help to avoid foods that can worsen diarrhea, such as fried, fatty, or high-fiber foods.
If your diarrhea continues for more than a few days, talk to your prescriber. They may recommend stopping Gas-X to see if this symptom continues. If it does, your diarrhea is likely due to something else. They can help you figure out the cause, and recommend treatment if needed. In some cases, antidiarrheal medications may help, such as loperamide (Imodium A-D).
Does Gas-X really work? It might, but it depends on a few factors, including what’s causing your gas.
How much Gas-X should you take? The right daily Gas-X dosage is based on which product you’re taking.
How can you get rid of bloating? Explore tips for improving gas and bloating, including over-the-counter products to try and foods that are less likely to cause bloating.
If at any point you have a fever, bloody stool, or severe abdominal pain along with diarrhea, contact your healthcare professional immediately. These are signs that you need to be evaluated further.
Frequently asked questions
Yes, you can take Gas-X every day. But you shouldn’t take some products, such as Gas-X Total Relief, for more than 2 weeks without talking to a healthcare professional. Along with simethicone, this product also contains calcium carbonate.
To be safe, reach out to your healthcare professional if you need Gas-X for more than a couple weeks. They may want to evaluate the cause of your gas further, since gas can have many causes including constipation, medications, and gastroesophageal reflux disease (GERD). There’s less evidence that Gas-X is helpful for gas from conditions like constipation and GERD, so you may need another treatment.
Gas-X works in the stomach and intestines. It doesn't get absorbed by the body. So even if you accidentally take too much Gas-X, serious harm is unlikely.
Still, if you or someone you know has taken too much Gas-X, contact the National Poison Control Center at 1-800-222-1222 or call your healthcare professional. Certain Gas-X products, such as Gas-X Total Relief, contain other ingredients, such as calcium carbonate. Taking too much calcium carbonate can cause dangerous heart and kidney effects.
Gas-X doesn't have many drug interactions because it’s not well absorbed by the body. However, it’s best to avoid other medications that also contain simethicone or other ingredients in the Gas-X product you take (such as calcium carbonate).
Additionally, ask your pharmacist whether you should take any of your other medications on an empty stomach. If so, you may need to separate your Gas-X dose from these medications. Your pharmacist can let you know how far apart to space your doses.
The bottom line
Gas-X (simethicone) is typically taken to relieve gas. Gas-X isn’t absorbed into your bloodstream, so it has minimal side effects.
Some people report mild nausea and diarrhea with Gas-X. If these side effects persist, contact your healthcare professional. They may want to evaluate you further to see if something else is going on.
It may be possible to take Gas-X every day. But if you need it for more than a couple weeks, contact your prescriber. They can evaluate your gas symptoms and see if you’d benefit from another treatment.
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References
Ingold, C. J., et al. (2023). Simethicone. StatPearls.
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