Constipation and nausea are two digestive symptoms that can often appear together. While nausea is usually linked to infections, motion sickness, or food poisoning, constipation itself can also trigger feelings of queasiness.

Understanding how constipation affects the rest of your digestive system can help you manage both issues more effectively.

Why Constipation Causes Nausea

Think of your digestive system as plumbing in your home. When the pipes are blocked, waste builds up, and pressure starts to back up. Constipation works the same way.

When stool moves too slowly through the intestines or becomes impacted, it can press against the stomach. This pressure can cause bloating, discomfort, and nausea.

Eating while constipated may make things worse because slow intestinal motility (slower food movement in the GI tract) allows food to sit in your stomach longer, creating a sense of fullness and queasiness.

Dr. Elana Maser, a gastroenterologist at the Icahn School of Medicine at Mount Sinai, explained that some patients feel nauseated because food doesn’t move quickly and “just sits in the stomach due to generalized slow motility.”

Other Possible Causes of Nausea

It’s important to remember that constipation isn’t the only reason for nausea. Other possible causes include:

  • Certain medications (e.g., chemotherapy or painkillers)

  • Dehydration

  • Food poisoning

  • Gastroesophageal reflux disease (GERD)

  • GI infections like gastroenteritis

  • Intestinal obstruction (a serious condition where food or stool cannot move through)

  • Irritable bowel syndrome (IBS)

  • Migraines

  • Pregnancy-related morning sickness

  • Motion sickness

  • Peptic ulcers

If constipation and nausea occur together, it’s often because both are linked to sluggish digestion or intestinal blockage.

Home Remedies for Constipation and Nausea

Mild cases can often be treated at home with lifestyle changes and simple remedies.

For Constipation:

  • Drink more water throughout the day

  • Eat fiber-rich foods (fruits, vegetables, whole grains, legumes)

  • Exercise regularly to improve bowel motility

  • Go to the bathroom when you feel the urge instead of holding it

  • Establish bowel training routines (going at the same time daily)

For Nausea:

  • Sit in a quiet, well-ventilated environment

  • Get fresh air

  • Eat bland, easy-to-digest foods like crackers, toast, or baked chicken

  • Try natural remedies such as ginger tea or ginger ale

  • Avoid lying down immediately after eating

  • Choose foods high in water content, like popsicles or watermelon

Medications for Relief

If home remedies aren’t enough, certain medications may help:

  • Anti-nausea medications: OTC or prescription, though they usually take 30–60 minutes to work

  • OTC laxatives or stool softeners: May relieve constipation

⚠️ However, caution is needed:

  • Some anti-nausea drugs (like Zofran) can cause constipation.

  • Some laxatives may trigger nausea or other side effects.

Always consult with a healthcare provider before combining treatments, especially if you’re already taking prescribed medications.

When To See a Healthcare Provider

Occasional constipation and nausea are usually not dangerous, but persistent or severe symptoms should not be ignored.

Seek medical attention if you experience:

  • Nausea lasting more than 48 hours

  • Vomiting multiple times in a day

  • Inability to keep down food or liquids

  • Severe stomach pain or bloating

  • Bloody stools

  • No bowel movement for more than three days

  • No urination for eight hours or longer

  • Fever with digestive symptoms

  • Weakness or dizziness

In rare cases, constipation with nausea can be linked to neurological conditions such as multiple sclerosis or Parkinson’s disease, though most cases are not related to these disorders.

A Quick Review

Constipation can cause nausea because stool buildup increases pressure in the intestines and slows food movement through the stomach. While other conditions can also cause nausea, constipation is a common and often overlooked trigger.

Treatments include lifestyle adjustments like hydration, fiber, exercise, and bland foods, as well as medications when necessary. If constipation and nausea persist or appear alongside severe symptoms such as fever, blood in stool, or vomiting, seek professional medical care.