Diarrhea that has a particularly foul odor can be caused by an infection or other underlying condition. The smell is usually due to the presence of bacteria, parasites, or the byproducts of infection. Some common causes of smelly diarrhea include:
- Bacterial infections
- Parasitic infections
- Inflammatory bowel diseases
- Malabsorption disorders
- Food intolerances
If your diarrhea has an unusually bad odor, it’s important to see your doctor to determine the cause. Treatment will depend on the specific condition leading to the smelly diarrhea. Getting to the root of the problem can help resolve symptoms and prevent complications.
What Causes Smelly Diarrhea?
There are several possible causes for diarrhea that smells particularly foul:
Bacterial Infections
Bacterial infections are a common cause of smelly diarrhea. Some types of bacteria that can lead to foul-smelling stool include:
- Salmonella
- Shigella
- Campylobacter
- Clostridium difficile (C. diff)
These bacteria can cause inflammation and ulcers in the intestines, altering digestion and leading to smelly diarrhea. Salmonella and Campylobacter are often contracted through undercooked poultry. Shigella spreads through contact with contaminated feces and causes dysentery. C. diff is an infection that occurs after antibiotic use disrupts the normal gut microbiome.
In addition to smelly diarrhea, bacterial infections may cause abdominal cramps, fever, nausea, and blood or mucus in the stool. Diarrhea will usually last several days but can persist for a week or more without treatment.
Parasitic Infections
Parasites like Giardia and Cryptosporidium can also infect the gastrointestinal tract and lead to foul-smelling diarrhea. These microscopic organisms are typically spread through contaminated food and water sources.
In addition to smelly diarrhea, parasitic infections may lead to gas, bloating, nausea, weight loss, and greasy stool. Symptoms can wax and wane over months if left untreated.
Inflammatory Bowel Diseases
Inflammatory bowel diseases (IBD) like Crohn’s disease and ulcerative colitis cause chronic inflammation and damage in the digestive tract. This can alter digestion and create excess foul-smelling gas and diarrhea.
Other symptoms of IBD include abdominal pain, rectal bleeding, reduced appetite, and unintended weight loss. Symptoms vary in severity over time, with periodic flare-ups causing very smelly diarrhea.
Malabsorption Disorders
Conditions that affect the absorption of nutrients like celiac disease, short bowel syndrome, and exocrine pancreatic insufficiency can also lead to smelly diarrhea.
When food is not properly digested, excess fats, proteins, and carbs make their way to the colon and become food for gas-producing gut bacteria. This can increasevery foul-smelling flatulence along with diarrhea containing undigested fat.
Weight loss, bloating, abdominal pain, and fatigue are other common symptoms with malabsorption disorders.
Food Intolerance
Intolerance to foods like dairy, wheat, or other ingredients can damage the intestines and also lead to smelly diarrhea in some cases. This occurs when the offending foods trigger inflammation in the gastrointestinal tract.
Symptoms of food intolerance may come on shortly after consuming the trigger food. Bloating, abdominal discomfort, nausea, and smelly diarrhea are common. The smell is caused by inflammation making stool pass rapidly through the intestines before it can be properly digested and absorbed.
When to See a Doctor
It’s important to consult a doctor if you notice any of the following with smelly diarrhea:
- Diarrhea that lasts more than 3 days
- Fever over 101.5°F (38.5°C)
- Bloody or black stool
- Intense or worsening abdominal pain
- Signs of dehydration like dizziness, dry mouth, or dark urine
Prompt medical care can determine the cause of foul-smelling diarrhea and get you the appropriate treatment. This is especially crucial for vulnerable groups like infants, the elderly, or immunocompromised patients.
Seeking timely treatment helps avoid complications like dehydration, electrolyte abnormalities, malnutrition, and sepsis in severe cases.
Diagnosing the Cause
To determine the cause of smelly diarrhea, the doctor will typically:
- Ask about your symptoms and medical history
- Perform a physical exam
- Order lab tests on your stool sample
- Arrange imaging tests if IBD is suspected
Examining stool under a microscope can often reveal bacterial, parasitic, or white blood cells that point to infection or inflammation. Stool cultures can also isolate specific pathogens like Salmonella.
Blood tests help look for signs of infection while also checking for dehydration and electrolyte abnormalities. Your doctor may order a CT scan or colonoscopy if inflammatory bowel disease is suspected.
Once the cause is found, appropriate treatment can begin.
Treatments for Smelly Diarrhea
Treatment depends on the underlying cause of the smelly diarrhea:
Bacterial Infections
Bacterial infections are treated with antibiotics, with the specific type depending on lab results. Severe dehydration from diarrhea is corrected with IV fluids. Over-the-counter anti-diarrheal medication may also provide symptom relief. Most bacterial infections resolve in 5-7 days with proper antibiotics.
Parasitic Infections
Prescription anti-parasitic medications are used to eradicate Giardia, Cryptosporidium, and other parasites. Metronidazole or nitazoxanide are commonly prescribed. These treatments are usually given for 5-10 days.
Inflammatory Bowel Diseases
There is no cure for Crohn’s or colitis, but various medications can induce remission and reduce smelly diarrhea. Medications used include aminosalicylates, steroids, immunosuppressants, and biologics to control inflammation. Surgery may be required in severe cases not responding to medications.
Malabsorption Disorders
This involves treating the underlying condition causing malabsorption. A gluten-free diet treats celiac disease, while pancreatic enzyme supplements aid digestion for those with exocrine pancreatic insufficiency. Short bowel syndrome may require IV nutrition or intestinal transplantation in severe cases.
Food Intolerance
Eliminating problem foods from the diet, like dairy or gluten, can prevent smelly diarrhea in those with food intolerances. Taking over-the-counter products like Lactaid can aid digestion of problematic foods.
Lifestyle Changes for Better Digestive Health
In addition to specific medical treatments, certain lifestyle changes may help reduce instances of smelly diarrhea:
- Diet: Eat more whole foods high in fiber like fruits, vegetables, whole grains, beans, and nuts. Limit fatty, sugary, and processed foods which can irritate the GI tract.
- Hydration: Drink plenty of fluids, especially with diarrhea. Water, oral rehydration solutions, clear broths, and diluted juices help replenish lost fluids.
- Probiotics: Consume probiotic foods like yogurt, kefir, kimchi, and kombucha to support the growth of beneficial gut bacteria.
- Exercise: Regular physical activity stimulates digestion and reduces inflammation. Aim for 30 minutes per day of moderate exercise.
- Stress management: Chronic stress can alter gut microbiota and worsen digestive issues. Try relaxing practices like yoga, meditation, deep breathing, or Tai Chi.
Making dietary changes, staying hydrated, managing stress levels, and getting regular exercise can all help maintain healthy digestion and potentially reduce smelly diarrhea.
When to Seek Emergency Care
In severe cases of smelly diarrhea with dehydration, electrolyte imbalance, or signs of sepsis, emergency medical care is needed. Go to an emergency room or call 911 if you experience:
- Little or no urine output
- Racing heart or palpitations
- Fainting or loss of consciousness
- Difficulty breathing
- High fever with shaking chills
Infants with smelly diarrhea accompanied by lethargy, severe crying, dry mouth/eyes, or sunken soft spot on the skull also warrant emergency medical care.
Prolonged or excessive loss of fluids and electrolytes can be life-threatening. Sepsis is a systemic, potentially fatal immune reaction triggered by infection. Quick intervention with IV fluids, electrolyte correction, and antibiotics in the ER can prevent serious complications in these situations.
Can Smelly Diarrhea Go Away On Its Own?
Mild or transient cases of smelly diarrhea may resolve on their own. Traveler’s diarrhea, food poisoning, or occasional loose stools with smelly gas can often clear up within a few days.
However, ongoing smelly diarrhea lasting more than 3 days requires medical assessment. Chronic loose stools with a foul odor can indicate an underlying infection, inflammatory condition, or disorder interfering with nutrient absorption.
Trying to treat smelly diarrhea on your own with over-the-counter medications can prolong illness and lead to complications. Only your doctor can accurately diagnose the cause and provide appropriate treatment to address smelly diarrhea along with any related medical issues.
How To Reduce the Smell of Diarrhea at Home
You can try these home care tips to help minimize the smell from diarrhea:
- Drink plenty of clear fluids to dilute stool
- Avoid gas-producing foods like beans, dairy, carbonated drinks
- Take over-the-counter simethicone to reduce gas
- Take probiotic supplements to support healthy gut bacteria
- Use air freshening products like candles, sprays, gels
- Open windows to ventilate restroom after use
- Cleanse with soaps containing tea tree oil or eucalyptus
However, the primary way to reduce foul odor is to treat the underlying cause with medical care. Once the smelly diarrhea resolves, gas and odor dissipate as well.
Preventing Smelly Diarrhea
You can reduce your risk of developing smelly diarrhea by:
- Practicing good hand hygiene, especially before eating
- Thoroughly cooking meats, eggs, and fish
- Only drinking purified water when traveling
- Washing all fruits and vegetables
- Avoiding contaminated sources like public pools or hot tubs
- Getting regular stool analysis if you have IBD
- Learning your food intolerances and avoid trigger foods
Proper hygiene, food safety, and disease management limit exposure to common infections and irritants that cause smelly diarrhea. However, seek prompt treatment if foul-smelling diarrhea arises, as untreated conditions can worsen.
Conclusion
Diarrhea with a very foul, abnormal odor is usually due to infection or inflammation in the gastrointestinal tract. Common causes include bacterial or parasitic infections, IBD, malabsorption disorders, and food intolerances.
See a doctor if smelly diarrhea persists to get an accurate diagnosis and appropriate treatment. This can correct malnutrition, dehydration, and electrolyte imbalances that occur with ongoing diarrhea.
While embarrassing to discuss, don’t ignore abnormally smelly diarrhea. With proper medical care, this troubling symptom can be relieved and your digestive health restored. Paying attention to your body and seeking help for changes from normal patterns are key to staying healthy.