Left-sided abdominal pain has many possible causes, ranging from trapped gas to conditions that need prompt medical attention. The left side of your abdomen houses your stomach, spleen, pancreas tail, left kidney, and portions of your colon, so pain in this area can originate from any of these organs. Where exactly you feel the pain, whether it’s upper or lower, and what other symptoms you have are the biggest clues to what’s going on.
Upper Left vs. Lower Left: Why Location Matters
Your left upper abdomen contains your stomach, spleen, the main body of your pancreas, the left portion of your kidney, your adrenal gland, and a sharp bend in your colon called the splenic flexure. Your left lower abdomen contains the sigmoid colon (the S-shaped end of your large intestine) and, in women, the left ovary and fallopian tube.
Pain high up, near or under your ribs, points toward your stomach, spleen, or pancreas. Pain lower down, near your hip bone, is more likely related to your colon, a kidney stone that has moved into the lower urinary tract, or a gynecological issue. Some conditions, like kidney stones, can produce pain that shifts location as the stone travels.
Trapped Gas and Splenic Flexure Syndrome
One of the most common and least dangerous causes of left-sided pain is simply gas. Your colon makes a sharp turn beneath your left ribcage at a point called the splenic flexure. Gas traveling through your large intestine normally negotiates this curve without trouble, but when too much gas builds up, it can get stuck at the bend and stretch the colon wall. The result is a sharp, cramping pain in your upper left abdomen that can feel alarmingly intense.
This is sometimes called splenic flexure syndrome. Some people are born with a tighter-than-average bend in their colon, making them more prone to it. The pain typically eases once you pass gas or have a bowel movement. Carbonated drinks, high-fiber foods, and swallowing air while eating quickly are common triggers. If this kind of pain comes and goes and reliably resolves with gas, it’s almost certainly not dangerous.
Gastritis and Stomach Ulcers
Your stomach sits in the upper left part of your abdomen, and inflammation of its lining (gastritis) is a frequent source of pain there. Gastritis typically causes a burning or gnawing sensation between meals or at night, when stomach acid contacts inflamed tissue without food to buffer it. Spicy food, alcohol, long-term use of anti-inflammatory painkillers, and infection with a common bacterium called H. pylori are the usual culprits.
Stomach ulcers produce similar pain but with a slightly different pattern. You may feel intensely hungry one to three hours after eating, because the ulcer is exposed as your stomach empties. Both conditions can also cause nausea, bloating, and a feeling of fullness. If you notice dark or tarry stools, or if you’re vomiting material that looks like coffee grounds, that suggests bleeding and needs immediate medical attention.
Diverticulitis
If your pain is in the lower left abdomen, diverticulitis is one of the most important possibilities to consider. Small pouches can form in the wall of your colon over time, and when one of those pouches becomes inflamed or infected, the result is diverticulitis. The lower left abdomen is the most common location for this pain because the sigmoid colon, where pouches tend to develop, sits there.
The pain is usually sudden and can be intense, though in some cases it starts mild and worsens over several days. Along with pain, you may notice fever, nausea, and a change in bowel habits like sudden diarrhea or constipation. Your abdomen may feel tender when you press on it. Diverticulitis has historically been considered a condition of older adults, but rates among people aged 18 to 44 have risen significantly in recent years. A 132% increase in acute cases was documented among people in their 40s between 1980 and 2007.
Mild diverticulitis can sometimes be managed at home with a temporary change in diet, but more severe cases require antibiotics or, rarely, surgery. Constant lower left pain with fever and bowel changes warrants a call to your doctor or a visit to urgent care.
Kidney Stones
A stone forming in or passing through your left kidney can produce pain anywhere from your mid-back to your lower abdomen and groin on the left side. Kidney stone pain is often described as one of the most intense types of pain people experience. It typically comes in waves, building to a sharp peak and then easing before returning. You may also notice blood in your urine (it can look pink, red, or brown) along with nausea and vomiting.
The pain tends to shift as the stone moves. It may start in your flank (the area between your ribs and hip on your back) and migrate toward your lower abdomen or groin as the stone travels down the ureter toward your bladder. If you’re experiencing this wave-like, radiating pattern of pain, especially with bloody urine, a kidney stone is a strong possibility.
Enlarged Spleen
Your spleen sits just under your left ribcage, and when it becomes enlarged, it can cause pain or a feeling of uncomfortable fullness in the upper left abdomen. That pain sometimes spreads to your left shoulder. You might feel full after eating only a small amount, because the swollen spleen presses against your stomach.
Many different conditions can cause the spleen to enlarge. Viral infections like mononucleosis are a common trigger, especially in younger adults. Liver disease, certain blood disorders, autoimmune conditions like lupus, and some cancers of the blood or lymphatic system can also be responsible. An enlarged spleen is not something you can diagnose yourself, but persistent fullness or pain under your left ribs, especially after a recent illness, is worth getting checked.
Pancreatitis
The pancreas stretches across your upper abdomen, and inflammation of this organ causes severe upper abdominal pain that often radiates straight through to your back. The pain tends to come on suddenly and can be intense enough to make it hard to find a comfortable position. Eating, particularly fatty foods, usually makes it worse. Nausea and vomiting are common.
Gallstones and heavy alcohol use are the two leading triggers. Pancreatitis pain can feel like it’s centered slightly to the left or right depending on which part of the organ is most affected, but it generally spans the upper abdomen. This is a condition that often requires hospital care, especially if the pain is severe and you can’t keep fluids down.
Gynecological Causes in Women
Women experiencing lower left abdominal pain have a few additional possibilities. An ovarian cyst on the left ovary can cause a dull ache or sudden sharp pain if it ruptures or twists. Endometriosis, where tissue similar to the uterine lining grows outside the uterus, can cause pain on one or both sides that tends to worsen around your period. An ectopic pregnancy, where a fertilized egg implants in the left fallopian tube instead of the uterus, causes sharp lower left pain and is a medical emergency.
Signs That Need Urgent Attention
Most episodes of left-sided abdominal pain resolve on their own or turn out to be something manageable. But certain combinations of symptoms signal something more serious. Seek emergency care if your pain is accompanied by an inability to keep liquids down, if you’re unable to have a bowel movement and the pain is severe, or if your abdomen is visibly swollen and rigid. Pain that gets worse when you move, cough, or take deep breaths also warrants prompt evaluation.
If you’ve had abdominal surgery in the past and develop pain that feels similar to a previous episode but more severe or different in character, that’s another reason to get seen quickly. Constant, unexplained abdominal pain lasting more than a few hours, particularly with fever, is not something to wait out at home.