Can Constipation Cause Nausea?

Nausea is the uncomfortable sensation of feeling like you have to vomit, whether you do or not. You may be nauseous for several reasons, such as food poisoning or motion sickness. As you may be used to the typical reasons for nausea, you might not question if constipation can make you feel queasy.

The fact is that constipation can cause nausea based on the way your digestive system is structured. Here's what you need to know about the link between nausea and constipation, how to treat the nausea, and when to seek medical attention.

Nausea and Constipation

Why nausea and constipation are connected has to do with the basic anatomy of the human digestive system. In this case, it's helpful to think of the digestive system like the plumbing in your home, Rudolph Bedford, MD, a gastroenterologist at Providence Saint John's Health Center in Santa Monica, CA, told Health.

"If things aren't going down the drain, things are backing up in your sink," said Dr. Bedford. In the case of constipation, when stool blocks the route through your intestine, it can cause a backup in your stomach. One review explained that the pressure of stool in your colon can press against the walls of the stomach, leading to nausea.

Eating while constipated may also contribute to nausea. Slow motility—when there's slower food movement within the GI tract—may result in feeling nauseous.

"Sometimes people will feel nauseated because what they ate didn't pass through or is sitting in their stomach because of generalized slow motility," Elana Maser, MD, assistant professor of gastroenterology at the Icahn School of Medicine at Mount Sinai and gastroenterologist at the Feinstein IBD Center at Mount Sinai Hospital in New York City told Health.

Other Possible Causes

You might also be experiencing nausea for other reasons. Additional causes for nausea include:

• Certain medications, such as cancer treatments
• Dehydration
• Food poisoning
• Gastroesophageal reflux disease (GERD)
• Gastrointestinal (GI) infections, such as gastroenteritis—an intestinal infection
• Intestinal obstruction—when food or stool doesn't move through the intestines
• Irritable bowel syndrome (IBS)
• Migraines
• Morning sickness due to pregnancy
• Motion sickness
• Ulcers
  

Treatments

Different treatments may be necessary to relieve constipation and nausea if you have both at the same time. Treatments can include home remedies and medications.

Home Remedies

Sitting still in a quiet environment is a way to settle nausea. Another option is to get some fresh air if being in an odor-filled climate is contributing to the nausea.

To help prevent constipation in the first place, you can make some changes to your routine. Changes that can be beneficial include:

• Being physically active on a regular basis
• Consuming more fiber—but slowly increasing your intake
• Drinking more water
• Going to the bathroom when you feel the urge to go
• Training your bowels to make them regular

Eating bland foods like crackers or baked chicken and foods with high water content, like popsicles, are helpful for nausea and vomiting. It's also best to sit up and not lie down after eating. You can also try other food-based options: natural stomach soothers like ginger or ginger ale may help, said Dr. Bedford.

Medications

You can take anti-nausea medications to relieve nausea, but keep in mind that it can take 30 to 60 minutes for them to work. For constipation, you can use over-the-counter (OTC) laxatives or stool softeners if needed and appropriate. They promote easier bowel movements.

You'll want to talk with a healthcare provider before using these products. Remember also to check the side effects and potential drug interactions of any over-the-counter treatment you're taking. For example, anti-nausea medication, like Zofran, can cause constipation—exactly what you want to avoid. Laxatives can result in side effects, including nausea, rashes, and sore throat.

When To See a Healthcare Provider

If you're feeling constipation and nausea regularly, Dr. Maser suggested seeking advice from a professional. In rare cases, Dr. Maser cautioned that those two symptoms can be caused by multiple sclerosis or Parkinson's disease—though "most of the time there isn't an underlying condition; it's just constipation."

Medical attention is also necessary if you experience constipation and nausea with symptoms like:

• Bloating
• Bloody stools
• Fever
• Inability to keep foods or liquids down
• Nausea for more than 48 hours
• No bowel movements in three days
• No urination for eight hours or more
• Significant stomach pain
• Vomiting at least three times or more within a day
• Weakness

A Quick Review

You may be familiar with some causes of nausea, such as GI infections and migraines, but constipation is another reason you might feel nauseous. Slow-moving food and stool throughout the GI tract contribute to the link between constipation and nausea.

Treatments for constipation and nausea may include options like drinking more water, sitting still, or taking medications for each condition separately. Contact a healthcare provider if these treatments don't work or if you have other symptoms with constipation and nausea, such as abdominal pain, bloody stools, or weakness.