Pain on the left side of the body can have many causes, ranging from a simple muscle strain to conditions that need urgent attention. The meaning depends on where the pain is (chest, abdomen, back, arm, leg, or head), what it feels like, and what other symptoms are present.
Possible causes by location
Left chest or upper body
- Muscle strain or rib injury — pain that worsens with movement, twisting, or pressing on the area.
- Heart-related problems — left-sided chest discomfort, pressure, or squeezing pain (especially with shortness of breath, sweating, nausea, or pain spreading to the arm, jaw, or back) can be an emergency.
- Lung conditions — infections, inflammation, or other lung issues can cause pain with breathing or coughing.
Left upper abdomen
- Stomach problems — gas, reflux, gastritis, or ulcers may cause discomfort.
- Spleen-related issues — the spleen is located on the upper left side and can cause pain if enlarged or injured.
- Pancreas problems — inflammation of the pancreas can cause upper abdominal pain that may go to the back.
Left lower abdomen
- Constipation or trapped gas
- Diverticulitis — inflammation of small pouches in the colon, often causing left lower abdominal pain with fever or bowel changes.
- Urinary tract or kidney problems — may cause side/back pain, burning urination, or blood in urine.
Left back, hip, or leg
- Muscle strain
- Pinched nerves (such as sciatica) — may cause pain, tingling, or numbness traveling down the leg.
- Joint problems involving the spine, hip, or pelvis.
Left-sided weakness or numbness
Sudden weakness, numbness, facial drooping, trouble speaking, confusion, or loss of balance may be signs of a stroke and require emergency medical attention.
Seek urgent care if left-sided pain is:
- Sudden, severe, or worsening
- Associated with chest pressure, trouble breathing, fainting, or sweating
- Accompanied by weakness, confusion, or speech difficulty
- Associated with fever, vomiting, or blood in urine/stool
