Why does my left side under my breast hurt

Breast pain (mastalgia) can be described as tenderness, throbbing, sharp, stabbing, burning pain or tightness in the breast tissue. The pain may be constant or it may occur only occasionally, and it can occur in men, women and transgender people.

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Extramammary breast pain
When to see a doctor
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What causes a pain under the left breast?
What organ is on left side under breast?

Breast pain can range from mild to severe. It may occur:

Just a few days a month, in the two to three days leading up to a menstrual period. This normal, mild-to-moderate pain affects both breasts.
A week or longer each month, starting before a period and sometimes continuing through the menstrual cycle. The pain may be moderate or severe, and affects both breasts.
Throughout the month, not related to a menstrual cycle.

In men, breast pain is most commonly caused by a condition called "gynecomastia" (guy-nuh-koh-MAS-tee-uh). This refers to an increase in the amount of breast gland tissue that's caused by an imbalance of the hormones estrogen and testosterone. Gynecomastia can affect one or both breasts, sometimes unevenly.

In transgender women, hormone therapy may cause breast pain. In transgender men, breast pain may be caused by the minimal amount of breast tissue that may remain after a mastectomy.

Most times, breast pain signals a noncancerous (benign) breast condition and rarely indicates breast cancer. Unexplained breast pain that doesn't go away after one or two menstrual cycles, or that persists after menopause, or breast pain that doesn't seem to be related to hormone changes needs to be evaluated.

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Symptoms

Breast pain can be cyclic or noncyclic. Cyclic means that the pain occurs on a regular pattern. Noncyclic means that the pain is constant, or that there's not a regular pattern. Each type of breast pain has distinct characteristics.

Breast pain characteristicsCyclic breast painNoncyclic breast pain

Clearly related to the menstrual cycle and changing hormone levels
Described as dull, heavy or aching
Often accompanied by breast swelling, fullness or lumpiness
Usually affects both breasts, particularly the upper, outer portions, and can radiate to the underarm
Intensifies during the two weeks leading up to the start of the menstrual period, then eases up afterward
More likely to affect people in their 20s and 30s, as well as people in their 40s who are transitioning to menopause

Unrelated to the menstrual cycle
Described as tight, burning, stabbing or aching sensation
Constant or intermittent
Usually affects one breast, in a localized area, but may spread more diffusely across the breast
In women, most likely to occur after menopause

Extramammary breast pain

The term "extramammary" means "outside the breast." Extramammary breast pain feels like it starts in the breast tissue, but its source is actually outside the breast area. Pulling a muscle in the chest, for example, can cause pain in the chest wall or rib cage that spreads (radiates) to the breast. Arthritis that involves the cartilage in the chest, also known as costochondritis, can also cause pain.

When to see a doctor

Make an appointment with your doctor if breast pain:

Continues daily for more than a couple of weeks
Occurs in one specific area of your breast
Seems to be getting worse over time
Interferes with daily activities
Awakens you from sleep

Breast cancer risk is very low in people whose main symptom is breast pain, but if your doctor recommends an evaluation, it's important to follow through.

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What causes a pain under the left breast?

Causes include an injury to the rib cage, heavy lifting, an infection, and arthritis. Experts note, however, that it often has no identifiable cause. Your doctor may recommend OTC or prescription-strength pain relievers and anti-inflammatories or steroids. Heat and cold therapy and bed rest will help relieve the pain.

What organ is on left side under breast?

Your spleen is an organ that sits just below your left rib cage. Many conditions — including infections, liver disease and some cancers — can cause an enlarged spleen.