Clear Diarrhea: 4 Causes, Gastroenterologist Explains.

“Clear diarrhea” is not a medical term. We don’t use such terms in our daily medical practice.

The word “clear” means transparent or translucent. Water is an example of an ultimate clear fluid.

However, we use “watery diarrhea” to indicate its form, not the color or transparency.

Watery diarrhea can be brownish, yellowish, bright yellow, green, or black. Completely clear water from your colon is unlikely (unless you take a water enema).

So, the cause of your “clear diarrhea” depends on what you mean by “clear.” Some may mean “mucus-only stool,” while others mean pale or whitish diarrhea.

Possible causes of clear diarrhea include:

• Mucous diarrhea (scanty amount of clear diarrhea).
• Cholera (large volume rice-watery or clear diarrhea).
• Diarrhea with biliary disease (clay-colored stools).
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• Some medications, such as antacids and laxatives.
• Diarrhea in people with chronic liver disease.

1. Mucous diarrhea (clear diarrhea, small amount, jelly-like).

Severe forms of colon or rectum inflammation can cause mucus-only stool. We discussed the topic in this article “The urge to poop but only mucus comes out” and “pooping mucus only.”

The mucus is secreted from the inflamed colon or rectum walls. It is semi-fluid, semi-clear (whitish).

Symptoms of clear mucus-only stool (proctitis):

• Scanty amounts of gelly-like semi-clear substance (mucus).
• Tenesmus is a severe and recurrent urge to poop with only scanty amounts of clear mucus.
• Sense of rectal fullness and incomplete evacuation of the Bowel.
• Abdominal pain (usually in the lowermost part of your abdomen).
• With dysentery, the clear mucus can be mixed with blood.
• Rectal pain.
• Pain with bowel movements.

Causes of mucus-only stools:

• Dysentery (amoebic or bacillary dysentery).
• Irritable bowel syndrome (mucus with diarrhea is common with IBS, symptoms of proctitis may be absent).
• Inflammatory bowel diseases (Crohn’s disease and ulcerative colitis).
• Sexually transmitted diseases of the anorectal canal.
• Rectal ulcers.
• Antibiotic-associated diarrhea.
• Severe forms of food allergy or intolerance.
• Other rare causes include diversion colitis, rectal cancer, and radiation colitis.

Learn more about the above causes in this article.

2. Cholera infection (Large volume rice-watery or clear diarrhea).

Cholera is a life-threatening gut infection. It causes a severe form of watery diarrhea.

The picture below shows diarrhea from cholera. Massive loss of fluids can be soon fatal if not corrected.

{Image source}

The bacteria vibrio cholera causes cholera. It is transmitted through contaminated food and water.

Cholera is more prevalent in poor communities and countries where sanitation is inadequate.

Symptoms of cholera:

• The symptoms start one to two days after acquiring the infection. 
• Outbreaks in the community are common (due to water contamination).
• Severe forms cause massive watery diarrhea; the diarrhea is semi-clear or grayish water (similar to the water of boiled rice. 
• The rice water diarrhea has a characteristic fishy odor and contains flecks of mucus. 
• Early and mild stages of cholera may present with diarrhea with stool material and bile.
• Abdominal pain (usually mild).
• Vomiting is also common with cholera.
• Rapid, severe dehydration can lead to death within hours if not corrected. 
• Fever may occur, but less frequent.
• Loss of water and electrolytes such as potassium and calcium is common. This leads to complications such as shock, fainting, sunken eyes, and even renal failure.

Immediately call your doctor if you experience a sudden onset of large volume clear or greyish watery diarrhea.

Death reaches 70% if cholera is left untreated (reference). And the mortality is ten times higher in children than adults (reference).

The main treatment strategy is the rapid correction of water and electrolyte loss. Antibiotics also help rapid recovery.

3. Diarrhea with liver or biliary disease (clay stool).

The stool acquires its brown color from its bile content. Lack of bile in stool can result in pale, clay, or white stools.

When the condition is combined with diarrhea, some patients describe it as “clear diarrhea.”

The description of diarrhea with clay stools as “clear diarrhea” is inaccurate. But some patients use the term “clear diarrhea’ to describe such a condition.

What are the biliary and liver diseases that cause clay stool?

• Bile duct obstruction by a stone or cancer (usually cancer head of the pancreas).
• An early phase of hepatitis (called cholestatic phase): you probably see clear or clay diarrhea if your kid has Hepatitis A infection.
• Alcoholic hepatitis.
• Liver cirrhosis (live failure due to any cause): because it leads to decreased bile production.
• Less common conditions include biliary stricture (narrowing), Primary biliary cholangitis (an autoimmune disease), and bile duct cysts. 

Patients with such conditions usually have other symptoms. These include symptoms of bile obstruction and symptoms of liver disease, for example:

• Jaundice: yellowish sclera and skin. 
• Dark urine. 
• Abdominal pain.
• Itching.
• Nausea and vomiting.
• Symptoms of liver failure include abdominal swelling (ascites), swelling of the lower limbs (edema), loss of weight, …etc.

What are the characteristics of diarrhea with bile or liver disease?

Clay stools are not essentially loose. When diarrhea coexists with a biliary or liver disease, diarrhea can be described as clear diarrhea. Clear here doesn’t mean it is transparent.

Clear diarrhea here stands for pale whitish or greyish loose or watery stool. Liver or biliary disease is confirmed when clear or clay diarrhea is associated with symptoms

The image below will give you an idea of how the clay or pale diarrhea looks.

Clay diarrhea requires you to consult your doctor immediately. It is not a normal variant of stool. Clay stool or diarrhea often reflects a serious medical condition.

4. Drugs causing clear diarrhea?

Medications can cause clear diarrhea directly or by inducing liver or biliary disease.

Review your list of medications you’ve taken before the onset of clear diarrhea. 

Examples:

Antacid medications containing aluminum hydroxide.

Aluminum hydroxide is a syrup (suspension) used to treat gastritis and peptic ulcer disease.

Excessive use of aluminum hydroxide can result in clear white diarrhea.

Barium dye (used in imaging with X-ray or CT).

Barium is a contrast material used by radiologists. It is combined with X-rays, or computed tomography (CT) scans to obtain more information from the imaging.

Oral intake of barium in large amounts can cause white or clear stool.

Drugs that cause liver or biliary disease.

Medications can cause clear white stool or diarrhea via liver or biliary system affections.

This will cause symptoms discussed in the third section of this article (as jaundice). Examples include:

• Non-steroidal anti-inflammatory drugs (such as ibuprofen and diclofenac).
• Some antibiotics, such as ampicillin, amoxicillin-clavulanate, and macrolides. 
• Anabolic steroids and estrogens (contraceptive pills).
• Some antidepressants, such as tricyclic anti-depressant. 
• Others: the complete list of drugs that can cause jaundice and clay stools is HERE.

When to see a doctor for clear diarrhea?

Clear or white, or clay diarrhea usually requires medical attention. This is especially important if:

• Large volume diarrhea (frequent attacks of severe diarrhea).
• Frequent vomiting.
• Fever.
• Extreme abdominal pain.
• Jaundice (yellowish coloration of skin, eye whites, and urine).
• Fainting, rapid heartbeats, or shortness of breath. 
• In babies, signs of dehydration include sunken eyes, dry tongue, lack of seating and tears, and baby confusion. 

BONUS: some refer to the bright yellow diarrhea as clear diarrhea. Bright yellow diarrhea causes are mostly benign, such as stomach flu, indigestion of a large fatty meal, and others.

The causes of bright yellow water diarrhea are discussed here.

MORE: passing clear liquid from the Bowel.