Everything you need to know about fecal transplants

What is a fecal transplant?

A fecal transplant from a healthy donor encourages the recipient’s body to grow healthful bacteria, which can cure some infections and reduce the severity of certain gut health problems.

The gut is home to a delicate balance of millions of bacteria. When these bacteria become unbalanced, a person can develop diarrhea and other intestinal problems.

In some cases, the antibiotics that treat infections in the gut also kill off helpful bacteria. For example, about 20% of people who take antibiotics for Clostridium difficile, a common bacterial stomach infection that causes diarrhea, develop the condition again. This recurrence may be due to the antibiotics disrupting the gut microbiome, in which case, reintroducing good bacteria using a fecal transplant may help.

A doctor will carefully screen fecal transplant donors to ensure that their gut and feces are healthy. They will test them for various diseases, such as hepatitis.

In most cases, a doctor will deliver the donor feces to the recipient through a colonoscope. A colonoscope is a small, flexible tube that they can insert into the colon through the rectum. People usually take sedative drugs before the procedure, so they will not feel any pain or discomfort.

Another approach involves injecting liquid feces via an enema rather than using a colonoscope.

Fecal transplants originated in ancient Chinese medicine more than 1,700 years ago. In the past, this procedure involved drinking a liquid suspension of another person’s feces — a highly risky technique. Today’s fecal transplants are sterile and safe, and there is a growing body of research to support their use.

Uses

Doctors primarily use fecal transplants to treat C. difficile-associated disease (CDAD). In the United States, CDAD kills about 15,000 people each year, often due to severe colon inflammation.

Research consistently finds that fecal transplants are highly effective in treating this dangerous condition.

In a small-scale 2014 trial, 70% of the participants had no symptoms after one fecal transplant treatment. The overall cure rate was 90% among those who underwent multiple treatments. The participants also had fewer bowel movements and ranked their overall health more highly following treatment. Other studies have reported similar success rates.

Doctors may also recommend fecal transplants to manage other gastrointestinal conditions. For instance, problems with gut bacteria may cause or worsen inflammatory bowel disease (IBD).

Researchers have found that fecal transplants may help treat IBD, though their effectiveness varies among studies. A 2016 review found that success rates in trials ranged from 36.2% to 77.8%, pointing to a need for further research.

Fecal transplants may also help with irritable bowel syndrome (IBS), a poorly understood condition that causes a wide range of digestive problems.

Research on fecal transplants for this condition is still in its infancy, but the authors of the above review noted that in a study involving 13 people with IBS, a fecal transplant resolved symptoms in 70% of the participants.

Fecal transplant research

Research on the wider effects of gut bacteria is still developing, but if gut health does affect overall health, fecal transplants could eventually treat a variety of conditions.

Some research has linked gut health to other conditions, such as dementia. These associations may exist because gut health affects the body’s ability to absorb and use nutrients.

The authors of a 2016 review suggested that fecal transplants may eventually treat conditions such as:

• diabetes
• chronic fatigue syndrome
• fibromyalgia
• obesity
• mood disorders, such as depression
• nonalcoholic fatty liver disease
• hay fever
• arthritis
• asthma
• eczema

Risks and considerations

Most studies suggest that fecal transplants are safe, especially when the sample comes from a healthy, thoroughly vetted donor.

Doctors know less about the long-term safety of fecal transplants. As of 2019, a clinical trial is still assessing the long-term safety of fecal transplants via enema.

However, a recent fatality due to a severe, antibiotic-resistant infection developing after FMT has led to the U.S. Food and Drug Administration suspending all clinical trials that use the transplant.

They have issued an adverse event warning to healthcare providers.

Taking antibiotics after a fecal transplant may cause complications, so it is important to tell the doctor about any current medications and antibiotics. Likewise, a person should mention a recent fecal transplant if they are receiving antibiotics for an infection.

Although research has shown fecal transplants to be safe, many people feel anxious about the procedure.

Some worry that it is unsafe or dirty to transplant someone else’s feces into their body. However, people with chronic or life-threatening medical conditions may find that they can overlook the “yuck” factor.

A 2016 study identified several risk factors for fecal transplant failure, including:

• being female
• previous hospitalization
• recent surgery before the transplant

It can be difficult to access fecal transplants, especially for conditions other than CDAD.

Some people and a handful of natural health advocates suggest performing home fecal transplants by taking a pill or enema of feces from a healthy donor. However, no research supports doing fecal transplants at home, and there is no evidence that it is safe.

Without proper screening, a donor could transmit serious and potentially lethal diseases.

Summary

The idea of accepting feces from a healthy donor might seem peculiar, but the science supporting fecal transplants is becoming increasingly mainstream.

When other treatments fail, this innovative procedure may naturally restore the gut’s health, allowing beneficial bacteria to grow, fight infection, and improve a person’s health.

Not all doctors are knowledgeable about fecal transplants, so it is important to see an expert with sufficient experience of performing this procedure.