Lower right abdominal pain is one of the most common causes of patient visits to the emergency department. The lower right abdominal region is located below an imaginary horizontal line drawn under the lower right ribs and to the right of an imaginary vertical line running along the belly button.

Abdominal pain in this area is usually acute, and can be spontaneous or chronic. It can be a dull or sharp, localized or diffuse. Accompanying symptoms include nausea and vomiting, tenderness, constipation, diarrhea, loss of appetite, bloating and gas, and fever.

There are many structures in the lower right abdominal region in which pain can originate. The internal structures in this area include parts of the large intestine called the cecum, the appendix, and ascending colon, portions of the small intestine, the right ovary and the fallopian tube, and the right ureter. Any abnormality or disturbance of one or more of these structures can cause pain in the lower right abdomen.

Appendicitis
The most common cause of pain in the lower right portion of the abdomen is appendicitis, or an inflammation of the appendix. It occurs in about 10% of the population and it is most common between the ages of 10-30, although it may occur at any age.

The cause of appendicitis may be an infection or blockage, leading to inflammation and swelling. Symptoms usually begin as an aching pain around the belly button or in the middle of the upper abdomen, and then shifts to the lower right abdomen. This pain becomes sharper after several hours and is accompanied by tenderness or pain when exposed to pressure. When deep pressure is applied and released, a sharp pain or rebound tenderness is experienced. Accompanying symptoms include low-grade fever, nausea, vomiting, loss of appetite, and constipation or diarrhea.

Ovulation Pain
Pain associated with ovulation or Mittelschmerz may occur either in the right or left side of the lower abdomen. This usually does not require medical attention. However, it is sometimes confused with the symptoms of appendicitis due to the location of pain.

Ovulation pain occurs about two weeks before the next menstrual period, when an egg is released from the ovary. This may be a dull, cramp-like pain or a sharp, sudden pain. This pain is not usually severe, but it may be accompanied by vaginal spotting or bleeding. It is often relieved by rest and pain relievers, but if it is accompanied by fever and nausea, infections such as appendicitis must be considered.

Right Kidney Stones
Small, crystal deposits can form inside the kidneys, especially when urine becomes too concentrated. Kidney stones can pass through any part of the urinary tract, from the kidney to the bladder. This can be very painful, although the stones do not cause permanent damage.

Symptoms include severe pain below the right ribs, including the side and back, which may spread to the lower right abdominal area and groin. The pain may come in waves and fluctuate in severity. Associated symptoms include pain when urinating, pinkish, reddish or brownish urine that may be cloudy and foul-smelling, nausea, vomiting, fever with chills, and frequent urination.

Right Ovarian Cysts
The ovary sometimes produces fluid filled sacs on the surface, which may grow large and produce discomfort. Although they are usually harmless and can resolve on their own, they may become enlarged and get twisted, producing lower abdominal pains. They can produce dull, aching, pelvic pain that is persistent or intermittent, and may radiate to the lower back and thigh. Pelvic pains may be experienced near the beginning or end of a menstrual period. Menstrual periods may be irregular. Lower abdominal pain may also be associated with heaviness or fullness of the abdomen, nausea, vomiting and pressure on the bladder or rectum.