Pain on the left side of the body can come from many different causes—some minor, such as muscle strain, and some that need urgent attention. The meaning often depends on where the pain is located, what it feels like, and what other symptoms occur.
Possible Causes of Left-Sided Body Pain
1. Muscle strain or injury
- A pulled muscle from lifting, exercise, coughing, or awkward movement can cause pain on one side.
- Pain often worsens with movement or pressing on the area.
2. Nerve-related pain
- Problems such as a pinched nerve in the neck or back can cause:
- Sharp or burning pain
- Tingling or numbness
- Pain that travels into an arm or leg
3. Heart-related causes (important to recognize)
Left-sided discomfort—especially in the chest, shoulder, arm, jaw, or upper back—can sometimes be related to the heart.
Seek emergency help if pain is accompanied by:
- Chest pressure, squeezing, or heaviness
- Shortness of breath
- Sweating
- Nausea
- Dizziness or fainting
- Pain spreading to the left arm, jaw, or back
4. Digestive causes
Conditions such as gas, acid reflux, constipation, or stomach issues can sometimes cause pain on the left side of the abdomen or chest area.
5. Kidney or urinary problems
Left flank or back pain may be related to:
- Kidney stones
- Kidney infection
- Urinary tract problems
Possible warning signs include fever, painful urination, blood in urine, or severe waves of pain.
6. Shingles (herpes zoster)
- Can cause burning, tingling, or pain on one side of the body.
- A rash with blisters may appear days after the pain begins.
