Pain under the left armpit can be concerning, and many people associate any pain on the left side of their body with a heart attack. However, most of the time, pain under the left armpit has a less serious cause.
The armpit is a complex meeting point for muscles and connective tissues, lymph nodes, and blood vessels. As such, many issues in this area can lead to pain.
Causes range from pulled muscles and mild allergic reactions to more severe issues, such as an underlying infection.
While many of the causes of left armpit pain are not harmful in the long term, anyone experiencing breathing difficulties and pain in their chest, jaw, or neck should see a doctor immediately.
Causes of left armpit pain include:
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