Lower left abdominal pain in males most commonly comes from diverticulitis, a condition where small pouches in the colon become inflamed. But several other causes range from digestive problems and kidney stones to male-specific issues like inguinal hernias and prostate inflammation. The location of the pain, how it started, and what other symptoms come with it all help narrow down the source.
Diverticulitis: The Most Common Cause
Diverticulitis is the single most likely explanation for sudden pain in the lower left abdomen, particularly if you’re over 40. Small pouches called diverticula form along the wall of the colon, usually in the lower left section (the sigmoid colon). These pouches are harmless on their own, but when one becomes infected or inflamed, the result is sharp, localized pain that can come on suddenly or build over several days.
The pain is often accompanied by fever, nausea, tenderness when you press on the area, and a change in bowel habits like sudden constipation or diarrhea. About 4% to 15% of people who have diverticula eventually develop diverticulitis, and the risk climbs with age. Interestingly, under age 50, diverticulosis is more common in men than women. The overall rate of diverticulitis jumped 26% between 1998 and 2005, with the sharpest increases among people aged 18 to 44.
About 15% of people with diverticulitis develop complications like abscesses, perforations, or blockages, which is why persistent or worsening pain in this area warrants medical attention even if you suspect a mild case.
Kidney Stones Passing Through the Ureter
A kidney stone that moves out of the kidney and into the ureter (the narrow tube connecting the kidney to the bladder) can cause intense, wave-like pain that radiates from the back or side down into the lower abdomen. If the stone is on the left side, the pain settles in the lower left quadrant. The pain typically comes and goes in severe spasms rather than staying constant, and people with kidney stones often can’t find a comfortable position. You may also notice blood in your urine, painful urination, or nausea.
Stones can lodge at different points along the ureter: near the kidney, in the middle section, or close to where the ureter connects to the bladder. The lower the stone travels, the more the pain shifts toward the lower abdomen and groin. Most small stones pass on their own within days to weeks, though larger ones sometimes need medical intervention.
Inguinal Hernia
Inguinal hernias occur when tissue, usually part of the intestine, pushes through a weak spot in the lower abdominal wall near the groin. This type of hernia is far more common in men because of the anatomy of the inguinal canal, the passage through which the spermatic cord travels. Direct inguinal hernias, which develop from a weakness in the canal wall that forms later in life, occur primarily in men.
The hallmark sign is a visible or palpable bulge in the groin or scrotum, along with a feeling of heaviness, burning, or aching discomfort in the lower abdomen. Symptoms get worse when you strain, lift, cough, or stand for extended periods, and tend to improve when you lie down. A hernia that becomes trapped (incarcerated) or loses its blood supply (strangulated) causes sudden, severe pain and requires emergency surgery.
Prostatitis and Chronic Pelvic Pain
The prostate gland sits just below the bladder, and inflammation here can send pain into the lower abdomen, genitals, perineum (the area between the scrotum and rectum), and lower back. Prostatitis can be caused by a bacterial infection or, more commonly, by a poorly understood condition called chronic pelvic pain syndrome where no infection is found.
Along with lower abdominal pain, prostatitis typically causes frequent or painful urination, difficulty starting or maintaining a stream, and sometimes pain during or after ejaculation. Bacterial prostatitis tends to come on quickly with fever and severe symptoms, while the chronic form produces lower-grade discomfort that persists for weeks or months.
Testicular Problems Causing Referred Pain
Lower abdominal pain in males sometimes originates not in the abdomen at all, but in the testicles. The nerves supplying the testicles connect to the same spinal cord segments as nerves serving abdominal organs, which means testicular pain can “refer” upward into the lower belly. In some cases of testicular torsion (where the testicle twists on its blood supply), abdominal pain is the primary complaint, and the testicular origin gets missed initially.
The mechanism works in multiple ways: testicular pain signals travel through shared nerve pathways to the brain, the twisted spermatic cord can pull on the lining of the abdominal cavity, and the tensed surrounding muscles can irritate nearby tissue. Testicular torsion is a surgical emergency that needs treatment within hours to save the testicle, so any sudden lower abdominal pain in a young male that comes with groin or scrotal discomfort, nausea, or a testicle that sits higher than usual needs immediate evaluation.
Inflammatory Bowel Disease
Ulcerative colitis targets the large intestine and often involves the sigmoid colon on the lower left side. During a flare, the inflamed colon produces cramping abdominal pain along with bloody diarrhea, urgency, and fatigue. Crohn’s disease can affect any part of the digestive tract and may also cause lower left pain depending on the location of inflammation.
Unlike diverticulitis, which tends to come on over days, IBD follows a pattern of flares and remissions over months to years. Ongoing abdominal pain that doesn’t improve, or that worsens over time, can signal an active flare, an intestinal blockage, or a severe infection of the colon. Weight loss, persistent diarrhea, and blood or mucus in the stool are key distinguishing features.
Abdominal Aortic Aneurysm
In men over 65, especially those with a history of smoking, a rare but dangerous cause of lower abdominal pain is an abdominal aortic aneurysm (AAA). This is a bulging or weakening in the wall of the body’s largest artery as it passes through the abdomen. Men develop AAAs much more often than women, and smoking is the single strongest risk factor because it damages the vessel wall over time.
A growing aneurysm can cause deep, constant pain in the belly or side, back pain, and a noticeable throbbing or pulsing sensation near the belly button. Many aneurysms produce no symptoms until they rupture, which is why men aged 65 to 75 who have ever smoked are recommended to get a one-time screening ultrasound. A sudden, severe onset of pain could signal a rupture and requires emergency care.
How the Cause Gets Identified
Doctors narrow down the diagnosis by combining your description of the pain with a physical exam, blood work, and often imaging. The character of the pain itself provides important clues: people with peritonitis (inflammation of the abdominal lining) tend to lie completely still because movement worsens the pain, while people with kidney stones can’t stay still at all. Fever points toward infection, though older adults and people with weakened immune systems can have infections without developing a fever.
Blood tests check for signs of infection or blood loss. For lower left quadrant pain specifically, CT scanning is the recommended imaging study because it can visualize the colon, kidneys, blood vessels, and surrounding structures in detail. Plain X-rays are cheaper and faster, and can pick up about 90% of kidney stones, signs of bowel obstruction, or free air that indicates a perforation somewhere in the digestive tract.
Signs That Need Urgent Attention
Certain features alongside lower left abdominal pain call for prompt medical evaluation:
- Sudden, severe pain that comes on without warning
- Pain that steadily worsens or doesn’t improve over 24 to 48 hours
- A rigid, swollen, or tender abdomen that hurts when touched
- Blood in your urine or stool
- Persistent fever, nausea, or vomiting
- Inability to have a bowel movement for several days
- Scrotal pain or swelling accompanying the abdominal pain
Many causes of lower left abdominal pain, like mild diverticulitis or a passing kidney stone, resolve with straightforward treatment. But because some possibilities (testicular torsion, a ruptured aneurysm, a strangulated hernia) are time-sensitive emergencies, pain that is severe, sudden, or accompanied by the symptoms above shouldn’t be waited out at home.