Lower right abdominal pain has dozens of possible causes, ranging from a pulled muscle to a surgical emergency like appendicitis. The location narrows things down because specific organs sit in that quadrant: the appendix, the end of the small intestine, the right ovary and fallopian tube in women, and the right inguinal canal where hernias commonly form. What the pain feels like, how it started, and what other symptoms accompany it are the biggest clues to its source.
Appendicitis
Appendicitis is the most well-known cause of lower right abdominal pain, and the one most people worry about first. The classic pattern is distinctive: pain starts around the belly button, hovers or comes and goes for several hours, then gradually shifts to the lower right side and intensifies. Nausea and vomiting typically develop during that transition. By the time the pain settles into the lower right quadrant, it becomes sharper and more focused.
During a physical exam, the first thing a provider checks is tenderness at a spot called McBurney’s point, located roughly one-third of the distance from the hip bone to the belly button. That’s where the appendix typically sits. Not everyone follows the textbook pattern, though. Some people feel pain in a slightly different spot, and others skip the early belly-button phase entirely. If the appendix ruptures, the pain may briefly improve before spreading across the entire abdomen, which signals a more dangerous situation.
In children, ultrasound is the recommended first imaging test rather than a CT scan. When ultrasound results are unclear, a surgeon may opt for observation with repeat exams, a second ultrasound, or an MRI before turning to CT.
Kidney Stones
A stone moving through the right ureter, the tube connecting the kidney to the bladder, can produce pain that lands squarely in the lower right abdomen. The classic version starts as sudden, severe flank pain and radiates downward and forward. A stone stuck in the middle section of the ureter is particularly tricky because the pain pattern closely mimics appendicitis on the right side.
The pain tends to come in waves (colicky pain) rather than staying constant, which helps distinguish it from appendicitis. About 85% of people with kidney stones have blood in their urine, but that means 15% don’t, so a clean urine test doesn’t rule stones out. As a stone moves closer to the bladder, you may feel the urge to urinate frequently, burning with urination, or pain that radiates to the groin, testicles, or vulvar area. Some people also experience nausea, vomiting, or even bowel symptoms like diarrhea.
Ovarian Cysts and Ectopic Pregnancy
In women, the right ovary is a common source of lower right abdominal pain. Ovarian cysts often cause a dull ache or sharp pain below the belly button toward one side. Many cysts are harmless and resolve on their own, but two complications can turn them into emergencies.
A ruptured cyst causes sudden, severe pelvic pain and can lead to significant internal bleeding. A large cyst can also cause the ovary to twist on itself (ovarian torsion), which cuts off its blood supply and produces intense pain along with nausea and vomiting. Signs of shock, including cold and clammy skin, rapid breathing, and lightheadedness, mean the situation is critical.
Ectopic pregnancy is another serious possibility for women of reproductive age. This occurs when a fertilized egg implants outside the uterus, most often in a fallopian tube. The first warning signs are usually light vaginal bleeding and pelvic pain. If the tube ruptures, heavy internal bleeding follows, causing extreme lightheadedness, fainting, and shock. One unusual red flag: shoulder pain or a sudden urge to have a bowel movement can signal blood leaking from the fallopian tube and irritating the diaphragm. Any combination of pelvic pain, vaginal bleeding, and lightheadedness in a woman who could be pregnant warrants immediate emergency care.
Inguinal Hernia
Inguinal hernias happen when tissue pushes through a weak spot in the lower abdominal wall near the groin. They develop on the right side more often than the left and are far more common in men, though women can get them too. The telltale sign is a visible or palpable bulge in the groin area (or scrotum in men), accompanied by discomfort, heaviness, or a burning sensation.
Hernia pain gets worse with straining, lifting, coughing, or standing for long periods and improves when you lie down. Many hernias can be gently pushed back into the abdomen. If a hernia becomes trapped and can’t be pushed back in, it may cut off blood supply to the tissue inside it, causing sudden, severe pain that needs emergency surgery.
Crohn’s Disease
Crohn’s disease most commonly affects the very end of the small intestine and the beginning of the large intestine, both of which sit in the lower right abdomen. That’s why people with undiagnosed Crohn’s sometimes end up in the emergency room with pain that looks like appendicitis. The difference is that Crohn’s pain is usually chronic or recurring rather than a single acute episode.
Other symptoms that point toward Crohn’s include persistent diarrhea (sometimes with blood), fatigue, unexplained weight loss, mouth sores, and fever. Some people develop pain or drainage around the anus from abnormal tunnels called fistulas. Crohn’s is a lifelong inflammatory condition, so the pain tends to flare up periodically rather than appearing once and resolving.
Mesenteric Lymphadenitis
This condition is especially common in children and is one of the top reasons kids end up with lower right abdominal pain that turns out not to be appendicitis. Mesenteric lymphadenitis is swelling of the lymph nodes in the tissue that anchors the intestines to the abdominal wall. The most common trigger is a viral infection like gastroenteritis (stomach flu).
The pain and tenderness can be convincing enough to mimic appendicitis, and distinguishing the two sometimes requires imaging. The key difference is context: mesenteric lymphadenitis typically follows a recent viral illness, and the child often has other signs of infection like a sore throat or runny nose. It usually resolves on its own without surgery.
Muscle and Soft Tissue Pain
Not all lower right abdominal pain comes from an organ. The psoas muscle, a deep hip flexor that runs from the lower spine through the pelvis, can produce pain in the groin, lower abdomen, hips, or lower back when strained or inflamed. The pain typically worsens with specific movements like standing up straight, walking, or lifting the leg, and it may be bad enough to cause limping.
Psoas syndrome is thought to be frequently misdiagnosed or missed entirely because it shares symptoms with hernias, hip injuries, and abdominal conditions. A key distinction is that muscle and soft tissue pain changes with position and movement, while organ-related pain generally doesn’t follow that pattern as clearly.
When Lower Right Pain Is an Emergency
Severe pain in the lower right abdomen warrants an emergency room visit on its own, but several additional symptoms raise the urgency further. These include pain that started mild but is steadily getting worse, vomiting blood, blood in your urine or stool, fever or chills, pain that spreads upward toward the chest or shoulder, shortness of breath, yellowing of the skin or eyes, and signs of shock like cold skin, rapid breathing, or feeling faint.
Pain that doesn’t go away or keeps returning also deserves medical evaluation, even if it’s not severe. Chronic or recurring lower right abdominal pain can signal conditions like Crohn’s disease, ovarian cysts, or a hernia that may worsen over time without treatment.