Anal Incontinence

Anal incontinence is a condition where you lose control over when gas or stool passes from your body. This can happen suddenly or without you even realizing it, affecting your daily life and confidence.

Table of contents

• What is anal incontinence?
• Other names for this condition
• Parts of the body involved
• How common is anal incontinence?
• Types of anal incontinence
• Signs and symptoms
• What causes anal incontinence?
• How the body controls bowel movements
• Medical evaluation and diagnosis
• Treatment options
• Lifestyle changes and self-management

fecal incontinence, bowel incontinence, accidental bowel leakage

What is anal incontinence?

Anal incontinence is the inability to control the passing of gas or stool from your body^[1]. When you have this condition, liquid or solid waste leaks out without your control. This can range from mild leakage when you pass gas to accidentally passing solid stool^[2].

This is a distressing condition that affects not only your physical health but also your emotional well-being and quality of life^[3]. Many people feel embarrassed about this problem, which can lead to isolation and difficulty in social situations. However, it’s important to know that effective treatments are available^[1].

Other names for this condition

Anal incontinence is also known as fecal incontinence, bowel incontinence, or accidental bowel leakage^[1][4].

• Rectum
• Anus
• Internal anal sphincter
• External anal sphincter
• Pelvic floor muscles

How common is anal incontinence?

Anal incontinence is very common, affecting about 1 in 3 people, though the actual number may be even higher^[2]. A population-based survey found that about 2.2% of people have significant incontinence^[3]. The condition is more common in women and older adults^[3].

Among women specifically, about 10% experience anal incontinence^[4]. For women living in the community, approximately 9% have accidental bowel leakage, while this increases to 45% among those living in nursing homes^[5].

Many people don’t talk about this problem because bathroom visits are private matters, so the true number of those affected may be higher than reported^[2]. People are often reluctant to mention it to their doctors because of embarrassment^[3].

Types of anal incontinence

There are two main types of anal incontinence, each with different characteristics^[1][2]:

Urge incontinence happens when you feel a sudden urge to have a bowel movement but cannot control it or make it to the toilet in time^[1]. This is the most common type and usually involves problems with the muscles that control your bowel movements^[2].

Passive incontinence occurs when stool passes without you even realizing you need to go^[1]. In this situation, your body isn’t registering that your rectum is full of stool. This type usually involves problems with how your nerves communicate with your muscles^[2].

Signs and symptoms

The main symptom of anal incontinence is not being able to control when you pass stool^[1]. Some people only have problems when they have diarrhea (loose, watery stools), while for others, it’s an ongoing experience^[2].

Common signs and symptoms include^[2][6][7]:

• Stool leaking when you pass gas
• Stool leaking when you’re physically active
• Feeling like you need to poo but not being able to get to the toilet in time
• Finding poo in your underwear after a regular bowel movement
• Not being able to get fully clean after going to the toilet
• Seeing streaks or stains of poo in your underwear
• Losing the ability to control your bowel movements entirely

You may also experience urgency to have a bowel movement or inability to delay having one^[6]. Anal incontinence may also happen as leakage of stool when you pass gas^[1].

What causes anal incontinence?

Several factors affect your ability to control bowel movements. The muscles in your pelvic floor, rectum, and anus must work correctly to hold stool and release it at the right time. Your nerves need to work with these muscles so your body knows when it’s time to go. You also need to be physically able to reach the toilet in time^[2].

The most common causes of anal incontinence include^[1][2]:

Diarrhea: Loose, watery stools are much harder for your muscles to hold in than firm ones. Over time, frequent diarrhea can weaken the muscles in your rectum and anus^[2].

Constipation: Frequent constipation can also weaken your rectal and anal muscles. Straining to poo can cause nerve damage. With chronic constipation, liquid parts of stool can seep out around the firm stool that’s stuck, leading to incontinence^[2].

Muscle damage: Damage can occur during a difficult vaginal delivery, especially when doctors use forceps or make a small cut called an episiotomy to make a larger opening for the baby^[2]. Surgery on your anal or rectal area, such as surgery to remove hemorrhoids or to treat an abscess or fistula, can also cause muscle damage^[2].

Nerve damage: Many of the same things that damage muscles, like surgery and difficult vaginal delivery, can also damage nerves^[2]. Certain medical conditions can also cause nerve damage, including diabetes, Parkinson’s disease, and stroke^[5].

Other risk factors include^[4][6]:

• Inflammatory bowel diseases such as ulcerative colitis or Crohn’s disease
• Chronic diarrhea
• Previous surgery on the colon or anus
• Pelvic radiation therapy for cancer
• Rectal prolapse
• Perineal tears during childbirth
• Aging

How the body controls bowel movements

Normal anal continence is a complex process that involves the rectum, the internal and external anal sphincter muscles, the pelvic floor, and related motor and sensory nerve pathways^[3]. These nerve pathways include local nervous structures in the wall of the rectum, sensory receptors in the pelvic floor and lining of the anal canal, regional spinal reflexes, and higher control centers in the brain that allow you to defer bowel movements until social conditions permit^[3].

The rectoanal inhibitory reflex is the lowering of resting sphincter pressures in response to rectal filling. This reflex plays a role in both sampling what’s in the rectum and in the process of having a bowel movement^[3]. When the anal canal becomes funnel-shaped, rectal contents gain access to specialized sensory tissue. This allows your body to sample the contents after each filling period. Continence is preserved by the external anal sphincter, which maintains a high-pressure zone in the lower part of the anal canal^[3].

With increasing degrees of rectal stretching, internal anal sphincter relaxation increases. If you defer having a bowel movement for too long, the external anal sphincter finally becomes tired and emptying becomes unavoidable^[3].

Another major factor in maintaining continence is rectal compliance, which is the ability of the rectum to expand and hold stool, allowing you to delay emptying^[3].

Medical evaluation and diagnosis

If you think you have anal incontinence, it’s important to see a doctor. The first step in treatment is to see a healthcare professional who will talk to you about the causes of the condition and how they can be treated^[9].

Medical history and interview: Your doctor will ask specific questions about your symptoms, including^[4][8]:

• How often do you experience anal incontinence?
• In what situations do you typically experience bowel leakage or pass gas accidentally?
• Do certain foods make your symptoms worse?
• What is the consistency of your bowel movements?

Keeping a diary of your bowel symptoms and habits may help you answer these questions^[4].

Physical examination: A physical exam is important and can identify conditions like rectal or vaginal prolapse, pelvic floor muscle problems, or hemorrhoids that may be related to your symptoms^[4]. Your doctor will examine the area around the anus to look for reflexes of the anal muscles and signs of unusual tissues. An exam with a gloved finger inserted in the anus can detect problems with muscles or other tissues of the rectum^[8].

Diagnostic tests: Your doctor may recommend additional testing to help identify issues with your pelvic floor muscles and anal sphincter^[4][8][5]:

Anorectal manometry involves inserting a narrow, flexible device into the anus and rectum. This test checks the strength or tone of the internal and external anal sphincter and how well the muscles and nerves of the anus and rectum work. It also measures how much the rectum can expand and its sensitivity^[5][8].

Anorectal ultrasonography (also called endoanal or pelvic floor ultrasound) produces video images of the rectum and anus to help your doctor evaluate the anal sphincter muscle structure^[5][4].

Balloon expulsion test involves inserting a small balloon into the rectum and filling it with water. You’ll be asked to go to the toilet to expel the balloon. This shows how well you can empty stool from the rectum^[8].

Proctography is an x-ray picture of the lower colon and rectum that gives information about how much and how well the rectum may hold and evacuate stool^[5].

Proctosigmoidoscopy is an internal visual examination of the rectum that allows the doctor to look for signs of disease or other problems that could cause anal incontinence^[5].

MRI defecography examines the positions of your pelvic organs when you have a bowel movement^[4].

Treatment options

The treatment you receive will depend on what’s causing your symptoms and how severe they are. Simple treatments such as diet changes, medicines, bowel training, and exercises to strengthen your pelvic floor muscles can improve symptoms by about 60 percent and can stop anal incontinence in 1 out of 5 people^[9].

Medications: Your doctor might recommend medicines to make you poo less often, such as loperamide (a drug that slows down the movement of food through your gut, allowing more water to be absorbed from stool), or medicines to soften your poo if constipation is the problem^[7][9][11]. Loperamide increases the time food takes to move through your gut, resulting in firmer, more easily controlled stool. It also increases internal anal sphincter tone^[11].

Pelvic floor physical therapy: Specialized physical therapists can help you learn how to improve your anal sphincter and pelvic floor muscle function. Exercises to strengthen your pelvic floor and the muscles around your bottom may be recommended^[7].

Biofeedback: This is a safe, minimally invasive behavioral technique that uses auditory or visual feedback to reeducate the pelvic floor muscles^[11]. Many studies have shown significant improvement in anal incontinence with biofeedback treatment^[11].

Products to help manage incontinence: Wearing absorbent pads inside your underwear is the most frequently used treatment for anal incontinence. For milder forms, wearing absorbent pads may make a big difference in your quality of life^[9]. Your doctor might also recommend incontinence pants, pads for inside your clothes or on your bed, or plugs that go inside your bottom to stop leaking^[7].

Sacral neuromodulation: This involves putting a small device under your skin in your bottom that uses electrical pulses to help you control when you poo^[7].

Surgery: You may have surgery if other treatments have not helped or your symptoms are severe^[7]. The standard surgical treatment for anal incontinence remains direct sphincter repair with an overlapping sphincteroplasty, which involves repairing the muscles in your bottom that control when you poo^[7][13]. Other surgical options include making a new anal sphincter using muscle taken from your thigh, putting an artificial sphincter in your bottom, or making a small opening in your tummy to attach a pouch to collect your poo^[7].

Lifestyle changes and self-management

Diet changes: Changing what you eat can help prevent or relieve your anal incontinence^[9]. Your doctor may recommend keeping a food diary to track what you eat each day, how much of certain foods you eat, when you eat, what symptoms you have, what types of bowel movements you have, when your anal incontinence happens, and which foods or drinks make your incontinence better or worse^[9].

If constipation or hemorrhoids are causing your anal incontinence, your doctor may recommend eating more fiber and drinking more liquids^[9]. Most women need to take a fiber supplement to make their stools more firm and bulky, which makes them easier to control^[17].

If you regularly have diarrhea, try to limit or avoid^[17]:

• Alcohol
• Caffeine found in coffee, tea, cola drinks, and chocolate
• Nicotine from smoking or chewing tobacco
• Gas-producing foods like beans, legumes, broccoli, cabbage, and brussels sprouts
• Dairy products if you have lactose intolerance
• Foods and drinks high in sugar, including fruit juice, soda, and candy
• Large amounts of foods high in fat
• Large amounts of certain artificial sweeteners like sorbitol and xylitol

General lifestyle recommendations: Your doctor or specialist may recommend the following changes^[7]:

• Try changing the position you sit in while pooing, such as using a squatting position—put your feet on a footstool while you sit on the toilet, so your knees are higher than your hips, and lean forward slightly
• Try to poo at regular times, such as after meals
• Keep a diary of your symptoms and what you eat and drink—you may notice some things make your bowel incontinence worse
• Plan an easy route to the toilet at home and when you’re out
• Wear clothing that’s easy to get off if you need to use the toilet in a rush
• Practise any exercises your doctor has recommended for your pelvic floor or muscles around your bottom
• Eat a balanced diet
• Quit smoking—nicotine can affect how quickly food moves through your digestive system
• Do not cut lots of foods and drinks from your diet at once—try one thing at a time to see if it helps your symptoms
• Try not to strain when you poo

Skin care: Your doctor may give you products to protect your skin, such as barrier cream or ointment, and may also give you advice on how to keep your skin clean^[7].