An ulcer is a painful sore that is slow to heal and sometimes recurs. Ulcers aren’t uncommon. How they appear and corresponding symptoms depend on what caused them and where they occur on your body.

Ulcers can appear anywhere in or on your body, from the lining in your stomach to the outer layer of your skin.

Some cases of ulcers disappear on their own, but others require medical treatment to prevent serious complications.

While the most common types of ulcers are peptic ulcers, there are many types, including:

Peptic ulcers

Peptic ulcers are sores or wounds that develop on the inside lining of your stomach, the upper portion of your small intestine, or your esophagus. They form when digestive juices damage the walls of your stomach or intestine.

Peptic ulcers are most often caused from inflammation after being infected with Helicobacter pylori (H. pylori) bacteria and long-term use of painkillers.

There are three types of peptic ulcers:

  • gastric ulcers, or ulcers that develop in the stomach lining
  • esophageal ulcers, or ulcers that develop in the esophagus
  • duodenal ulcers, or ulcers that develop in the duodenum (small intestine)

The most common symptom of this condition is a burning pain. Other symptoms may include:

Treatment depends on the underlying cause of your ulcer. If you have an H. pylori infection, your doctor may prescribe antibiotics to kill the harmful bacteria.

If your ulcers formed as a result of prolonged use of painkillers or medication, your doctor may prescribe medication that reduces your stomach acid or protectively coats your stomach to prevent acid damage.

Arterial ulcers

Arterial (ischemic) ulcers are open sores that primarily develop on the outer side of your ankle, feet, toes, and heels. Arterial ulcers develop from damage to the arteries due to lack of blood flow to tissue. These forms of ulcers can take months to heal and require proper treatment to prevent infection and further complications.

Arterial ulcers have a “punched out” appearance accompanied with a number of symptoms, including:

  • red, yellow, or black sores
  • hairless skin
  • leg pain
  • no bleeding
  • affected area cool to the touch from minimal blood circulation

Treatment for arterial ulcers depends on the underlying cause. Primary treatment includes restoring blood circulation to the affected area. While antibiotics may help reduce symptoms, your doctor may recommend surgery to increase blood flow to your tissues and organs. In more severe circumstances, your doctor may recommend amputation.

Venous ulcers

Venous ulcers — the most common type of leg ulcers — are open wounds often forming on your leg, below your knee and on the inner area of your ankle. They typically develop from damage to your veins caused by insufficient blood flow back to your heart.

In some cases, venous ulcers cause little to no pain unless they’re infected. Other cases of this condition can be very painful.

Other symptoms you may experience include:

Venous ulcers can take months to fully heal. In rare cases, they may never heal. Treatment focuses on improving flow to the affected area. Antibiotics can help prevent infection and reduce symptoms, but they aren’t enough to heal venous ulcers.

Alongside medication, your doctor may recommend surgery or compression therapy to increase blood flow.

Mouth ulcers

Mouth ulcers are small sores or lesions that develop in your mouth or the base of your gums. They’re commonly known as canker sores.

These ulcers are triggered by a number of causes, including:

Mouth ulcers are common and often go away within two weeks. They can be uncomfortable but shouldn’t cause significant pain. If a mouth ulcer is extremely painful or doesn’t go away within two weeks, seek immediate medical attention.

Minor mouth ulcers appear as small, round ulcers that leave no scarring. In more severe cases, they can develop into larger and deeper wounds. Other serious symptoms associated with this type of ulcer may include:

  • unusually slow healing (lasting longer than three weeks)
  • ulcers that extend to your lips
  • issues eating or drinking
  • fever
  • diarrhea

Mouth ulcers often go away on their own without treatment. If they become painful, your doctor or dentist may prescribe an antimicrobial mouthwash or ointment to reduce your discomfort.

If your condition is the result of a more serious infection, seek medical attention to receive the best treatment.

Genital ulcers

Genital ulcers are sores that develop on genital areas, including the penis, vagina, anus or surrounding areas. They are usually caused by sexually transmitted infections (STIs), but genital ulcers can also be triggered by trauma, inflammatory diseases, or allergic reactions to skin care products.

In addition to sores, symptoms that may accompany genital ulcers include:

Similar to types of ulcers, treatment depends on the underlying cause of your condition. In some cases, these sores will go away on their own. If diagnosed with an STI, your doctor may prescribe antiviral or antibiotic medication or ointment. If you feel you’ve been exposed to a STI, seek immediate medical attention.

Many cases of ulcers disappear on their own without treatment. However, ulcers can be an indication of a more serious condition. Visit your doctor to ensure you’re receiving the best treatment to improve your condition.