Hemorrhoids are swollen blood vessels within the anal canal/rectum (internal hemorrhoids) or around the opening of the anus (external hemorrhoids). Hemorrhoids result from the pathological enlargement of anal cushions. Anal cushions are a part of anal anatomy that help maintain continence (the ability to control bowel movements) by filling with blood to seal the rectum, and draining during defecation. If this filling and draining process isn’t working properly, they can become enlarged and cause symptoms. Hemorrhoids are generally not harmful, apart from causing discomfort.^[1]

Hemorrhoids are a common condition, with a U.S. survey finding a prevalence of 4.4% in the general public. However, some research reports rates of up to 40%.^[2][3] Hemorrhoids affect both sexes equally and prevalence peaks between ages 45 and 65.^[2] It’s suggested that by age 50, roughly half of people will have experienced hemorrhoids at some point in their life.^[4]

Hemorrhoids commonly cause rectal bleeding, itching, and pain. Sometimes, mucousy discharge or fecal soiling may also occur.^[1] If bleeding occurs, it is usually bright red, painless, and may be visible during or right after a bowel movement in the toilet bowl or on toilet paper.^[5] A study that assessed the frequency of hemorrhoids in participants undergoing colorectal cancer screening found that over half of individuals with hemorrhoid disease did not have any symptoms.^[3]

Symptoms can also depend on the type of hemorrhoid. External hemorrhoids may be visible as a swollen bump on the anal opening and can be quite painful, as the area has many nerves for sensing pain. Alternatively, internal hemorrhoids are usually not visible unless they are prolapsed (the blood vessel becomes displaced and protrudes out of the anus) and are often painless, as there are no pain receptors in that region of the rectum. Both types of hemorrhoids can become thrombosed, during which a harmless (but painful) blood clot forms in the hemorrhoid.^[1][4]

Many of the symptoms of hemorrhoids can occur due to other more serious health conditions and therefore proper diagnosis by a healthcare provider is always recommended.^[1]

A clinician usually diagnoses hemorrhoids with a physical exam, which may include an examination of the anus and rectum to check for visible hemorrhoids, or a digital rectal exam during which a finger is used to feel for any abnormalities in the rectum. Sometimes an endoscope may be required to diagnose internal hemorrhoids. The endoscope is a small tube with a light and camera that is inserted into the rectum to evaluate the inner tissues.^[1][3]

Internal hemorrhoids are often graded based on the degree of prolapse:^[6]

• Grade I: painless swelling of the hemorrhoid occurs.
• Grade II: hemorrhoid protrudes from the anus during bowel movements and spontaneously returns to normal position.
• Grade III: hemorrhoid protrudes from the anus during bowel movements and must be manually returned to position.
• Grade IV: hemorrhoid protrudes from the anus during bowel movements and cannot be returned to position.

The initial treatment of hemorrhoids usually involves lifestyle changes focused on reducing constipation, including consuming more fiber, increasing fluid intake, using stool softeners, avoiding straining on the toilet, and improving anal hygiene by cleansing with warm water and using unscented wipes in place of toilet paper.^[7]

Over-the-counter topical creams/ointments and suppositories containing a variety of ingredients (e.g., zinc, corticosteroids, anesthetics, phenylephrine) can improve symptoms temporarily, but there is little evidence to support their long-term efficacy and safety.^[7][6] Prescription topical medications containing nitroglycerin or nifedipine can also be helpful for managing pain.^[6]

For more severe hemorrhoids, or when initial treatments have failed, a clinician may perform nonsurgical (e.g., rubber band ligation) or surgical interventions (e.g., hemorrhoidectomy) to remove the hemorrhoid. However, these more invasive treatments are associated with a high risk of hemorrhoid recurrence and post-procedure pain.^[8][6]

Fiber supplementation helps to soften stool and reduce constipation, which can minimize irritation to the anal cushions and improve healing. A meta-analysis of controlled trials found that fiber supplementation, most often psyllium, reduced the risk of overall hemorrhoid symptoms by half and was particularly effective for reducing the risk of bleeding. However, it can take up to 6 weeks for these benefits to take effect. Once hemorrhoids have healed, fiber supplementation can be continued as a preventative measure.^[1]

Bioflavonoid supplementation, particularly micronized purified flavonoid fraction (MPFF) containing 90% diosmin and 10% hesperidin, was assessed in two recent meta-analyses of controlled trials. One meta-analysis reported a reduction in bleeding, anal leakage, and overall symptoms, while the other only found an effect for reduced bleeding.^[9][10] MPFF is thought to work by reducing vein inflammation and increasing vein tone (the tightness of the vein).^[9] While these products are commonly used in other parts of the world, they are not currently approved by the U.S. Food and Drug Administration for hemorrhoid treatment.^[6]

A high-fiber diet (25 to 35 grams daily), including adequate fluid intake, is considered to be the best first-line intervention for the management and prevention of hemorrhoids.^[11][6] Fiber is found in plant-based foods like vegetables, fruits, whole grains, legumes, nuts, and seeds. Sometimes, going from a low-fiber diet to a high-fiber diet can cause symptoms like bloating, gas, and abdominal discomfort, but slowly increasing fiber intake over time can help to minimize these symptoms. Observational research has suggested that higher consumption of spicy foods is associated with an increased risk of hemorrhoids, but this claim has not been supported by interventional trials.^[12][13][7]

Sitz baths, which involve sitting in a warm tub of water for 10 to 15 minutes several times a day, are often recommended by healthcare providers for hemorrhoids, but a meta-analysis was unable to find any strong evidence for improvements in pain or healing time. Regardless, people using a sitz bath often reported finding it soothing, and there is no apparent harm from the practice.^[14]

Pelvic floor physiotherapy may play a role in improving long-term outcomes for recurrent hemorrhoids for people with dyssynergic defecation, which is a pelvic floor dysfunction that can make bowel movements difficult. However, most of the research in this field has been related to anal fissures rather than hemorrhoids.^[8]

Although hemorrhoids are not fully understood, they are thought to occur when the connective tissues within the anal cushion weaken, allowing the blood vessels in the region to become enlarged and displaced.

Generally, hemorrhoids are associated with conditions that increase pressure in the abdomen or create a shear force against the anal cushions, such as:^{[6][8][3][11]}

• Constipation (either from hard or lumpy stool or straining during bowel movements)
• Pregnancy and vaginal delivery
• Chronic diarrhea
• Cirrhosis with ascites (fluid in the abdominal cavity)
• Obesity
• Anal intercourse
• Pelvic floor dysfunction