Published on: 6/18/2025
Swelling in the left arm can be caused by injury, infection, blood clots, lymphedema, or underlying medical conditions, and should be evaluated if it’s sudden, painful, or persistent.
If your left arm is swollen, some possible causes include:
Injury or trauma: A sprain, strain, or fracture can lead to localized swelling. Infection: Conditions like cellulitis can cause swelling, redness, and warmth. Blood clots (deep vein thrombosis): A clot in the veins of the arm can block blood flow and lead to sudden swelling. Lymphedema: A buildup of lymph fluid, often related to prior surgery or radiation, can cause one-sided arm swelling. Allergic reaction: A bite, sting, or exposure to an allergen may result in temporary swelling. Venous or lymphatic blockage: Obstruction in these systems may lead to fluid accumulation in the arm. Systemic conditions: Heart, liver, or kidney problems can also cause fluid buildup, although these usually affect both arms or legs.
If the swelling comes on suddenly, is painful, or is associated with other symptoms like redness, warmth, or shortness of breath, seek medical attention promptly.
(References)
We would love to help them too.
For First Time Users
We provide a database of explanations from real doctors on a range of medical topics. Get started by exploring our library of questions and topics you want to learn more about.
Was this page helpful?
Purpose and positioning of servicesUbie Doctor's Note is a service for informational purposes. The provision of information by physicians, medical professionals, etc. is not a medical treatment. If medical treatment is required, please consult your doctor or medical institution. We strive to provide reliable and accurate information, but we do not guarantee the completeness of the content. If you find any errors in the information, please contact us.