What underlying conditions could cause right arm swelling?

Swelling in the right arm may result from a variety of health issues, some minor and others more serious. Possible underlying causes include:

Deep vein thrombosis (DVT): A blood clot in the arm can cause sudden swelling, pain, and discoloration. Lymphedema: This occurs when lymph fluid builds up due to damage or removal of lymph nodes, often after cancer treatment. Infections: Cellulitis or other infections can cause redness, warmth, pain, and swelling in the arm. Injury or overuse: Muscle strains, sprains, or fractures can lead to localized swelling. Venous insufficiency: Poor blood flow in the veins can cause fluid buildup. Allergic reactions: A reaction to a bite, sting, or substance can lead to swelling in the affected area. Tumors or growths: Rarely, a mass pressing on blood vessels or lymphatic structures can block drainage and cause swelling.

If swelling is sudden, painful, or comes with other symptoms like fever, shortness of breath, or skin changes, seek medical attention promptly. You can also use a free symptom checker to help identify potential causes and determine the appropriate next steps for care.