Pain in the lower right side of your abdomen has several possible causes, ranging from temporary digestive issues to conditions that need prompt medical attention. The most well-known cause is appendicitis, but the lower right quadrant also contains parts of the colon, small intestine, the right ureter, and in women, the right ovary and fallopian tube. Any of these structures can produce pain when irritated, inflamed, or blocked.
Appendicitis: The Most Common Concern
Appendicitis is the first thing most people worry about when pain strikes in this area, and for good reason. It’s a genuine emergency that affects roughly 1 in 1,000 people each year. The pain follows a characteristic pattern: it typically starts as a vague ache around the belly button, hovers there or comes and goes for several hours, then intensifies and shifts to the lower right side. By the time it settles into that spot, it becomes sharper and steadily worse.
Along the way, nausea and vomiting usually develop, appetite disappears, and a low-grade fever may set in. The pain gets worse when you move, cough, sneeze, or take deep breaths. You may also notice bloating, constipation, diarrhea, or an inability to pass gas. If the pain started near your belly button and migrated to the lower right over six to twelve hours, that pattern is a strong signal that appendicitis is the cause.
Digestive Causes
The lower right abdomen houses the last section of the small intestine and the beginning of the large intestine, including a pouch called the cecum. Problems in this stretch of the digestive tract can mimic appendicitis closely.
Crohn’s disease most commonly affects the end of the small intestine, which sits in the lower right quadrant. Inflammation there produces cramping pain that tends to come and go over weeks or months, often accompanied by diarrhea, fatigue, and unintended weight loss. Unlike appendicitis, Crohn’s pain is recurring rather than a single acute episode.
Trapped gas and constipation are far more common and far less serious. Gas that collects in the ascending colon, which runs up the right side of the abdomen, can cause sharp, localized pain that resolves once the gas moves. Constipation can do the same, especially if stool backs up in the cecum. These causes tend to produce pain that shifts location, responds to passing gas or having a bowel movement, and doesn’t come with fever or vomiting.
Mesenteric Adenitis
In children and teenagers especially, swollen lymph nodes in the abdomen can cause pain on the lower right side that looks a lot like appendicitis. This condition, called mesenteric adenitis, usually follows a viral infection. It often comes with fever, nausea, diarrhea, and general stomach tenderness. It resolves on its own, but because it’s so similar to appendicitis, imaging is sometimes needed to tell the two apart.
Ovarian and Reproductive Causes
If you have ovaries, several gynecological conditions can produce right-sided lower abdominal pain. Ovarian cysts are extremely common and usually cause no symptoms at all. A large cyst on the right ovary, however, can create a dull ache or sharp pain below the belly button on that side, along with bloating and a feeling of pressure or heaviness.
Two complications make ovarian cysts more urgent. A ruptured cyst causes sudden, severe pain and can produce bleeding inside the pelvis. Ovarian torsion, where the ovary twists on its own blood supply, triggers intense pain along with nausea and vomiting. Both of these situations require emergency care. The key distinction from appendicitis is that the pain tends to sit lower in the pelvis and may coincide with your menstrual cycle.
An ectopic pregnancy, where a fertilized egg implants in the right fallopian tube instead of the uterus, also causes sharp lower right pain. This is a life-threatening emergency, and any woman of reproductive age with sudden pelvic pain and a missed period should be evaluated immediately.
Inguinal Hernia
Hernias in the groin are more common in men but can occur in anyone. An inguinal hernia happens when tissue pushes through a weak point in the abdominal wall near the pubic bone. The hallmark is a visible or palpable bulge that becomes more obvious when you stand up, cough, or strain. You may feel a burning or aching sensation at the bulge, along with pressure or discomfort in the groin when bending over or lifting. In men, the protruding tissue can descend into the scrotum and cause pain and swelling around the testicle.
Hernias aren’t always painful, and many people live with small ones for years. They become emergencies when the tissue gets trapped and its blood supply is cut off, causing sudden severe pain, nausea, and vomiting.
Kidney and Urinary Tract Causes
A kidney stone that gets stuck in the right ureter (the tube connecting the kidney to the bladder) can cause pain that radiates into the lower right abdomen and groin. This pain is usually severe and comes in waves. It starts in the side and back below the ribs, then spreads downward toward the lower stomach area. You may also notice blood in your urine, a burning sensation when urinating, or a frequent urge to go.
Urinary tract infections can occasionally produce lower abdominal discomfort, though the primary symptoms are usually burning with urination, urgency, and frequency rather than significant abdominal pain.
How to Tell What’s Serious
The character of the pain matters more than the location alone. Pain that started mild and has been getting steadily worse over hours is more concerning than pain that comes and goes or responds to a change in position. Several specific patterns warrant an emergency room visit:
- Pain so severe it interrupts your ability to function
- Pain with vomiting you can’t control or inability to keep liquids down
- Pain with fever, especially if the fever is climbing
- Inability to pass gas or have a bowel movement combined with worsening pain
- Pain that began near the belly button and moved to the lower right
- Sudden, severe onset with cold or clammy skin, rapid breathing, or lightheadedness
If you’ve had similar pain before but this episode feels different, more severe, or is accompanied by new symptoms like vomiting, that change alone is reason to get evaluated.
What Happens During Evaluation
When you go in for lower right abdominal pain, you’ll be asked about when the pain started, whether it moved from one location to another, and what other symptoms you’ve noticed. A physical exam will check for tenderness and whether pressing on the area and then releasing causes a spike of pain, which suggests inflammation of the abdominal lining.
For suspected appendicitis, ultrasound is the preferred first imaging test, particularly in children and young adults, because it avoids radiation exposure. A CT scan may follow if the ultrasound results are unclear. Blood work helps too: a high white blood cell count supports the possibility of infection or inflammation, though a normal count doesn’t rule it out entirely.
Many causes of lower right abdominal pain overlap in how they feel, which is why imaging and lab tests are often necessary to sort them out. The most important thing you can do is pay attention to the pattern: when the pain started, how it’s changed, and what other symptoms have appeared alongside it. That information helps narrow down the cause faster than anything else.