What could cause pain under both armpits without any lumps?

There are several reasons why you might feel pain in both your armpits without any lumps:

• Shoulder Injuries: Problems like rotator cuff tears or tendonitis in the shoulder can cause pain that spreads to the armpit area. When the shoulder muscles are injured, the pain can move to nearby places, including the armpit.
• Nerve Issues: Nerves that run through the shoulder also pass through the armpit. If these nerves are pinched or irritated, it can cause pain in both areas. Conditions like a pinched nerve in the neck can lead to pain that travels down to the shoulder and armpit.
• Muscle Strain: Straining muscles in the shoulder or upper back can create discomfort in the armpit as well. Overusing or injuring these muscles makes them sore and can lead to pain in connected regions.
• Joint Problems: Issues with the shoulder joint, such as arthritis, can cause widespread pain that includes the armpit. Inflammation in the joint affects the surrounding tissues, leading to discomfort in multiple areas.
• Referred Pain: Sometimes, pain from one part of the body is felt in another. Conditions affecting the heart or lungs can sometimes cause pain that appears in the shoulder and armpit, although this is less common.

If you are experiencing pain in both your armpit and shoulder, you can use our free AI symptom checker to better understand your symptoms and determine whether you should talk to a healthcare provider for further evaluation and treatment.