Feeling pain under your left breast can be especially worrying. After all, important organs and structures sit on that side of the body, like your heart, left lung, stomach, spleen, esophagus, ribs, and more. So, what happens if suddenly, you feel pain in that area? Is it necessarily a cause for concern?
First, don’t panic. It’s important to consider different factors before jumping to conclusions, says WH advisor Samantha Nazareth, MD. For example, how old are you? What you were doing when the pain began? What is your pain severity? You should also consider what your medical history entails, what medications you’re on, and if you have any other symptoms along with the pain, Dr. Nazareth says.
In some cases, pain under your left breast could be totally harmless, but other times, it might signal an underlying medical issue. Here are 10 possible reasons you might be experiencing pain under your left breast, according to doctors—and when to seek help.
Meet the experts: Samantha Nazareth, MD, is a board-certified gastroenterologist based in New York City and WH advisory board member. Jayne Morgan, MD, is a cardiologist and the Covid Task Force Clinical Director at the Piedmont Hospital in Atlanta.
What causes pain under your left breast?
1. Muscle Soreness
Experiencing slight physical discomfort is normal after an intense workout—it just means you committed (perhaps a little too hard). If you feel pain under your left breast after a chest-activating workout, like a bench or dumbbell press, there’s a good chance your muscles are sore. The area might be tender to the touch, and the pain might feel dull, tight, or achy for a few days, Dr. Nazareth says.
Soreness should go away within a few days to weeks. Resting and applying hot or cold therapy to the area can help, Dr. Nazareth says. Put crushed ice in a bag or use a hot compress or heating pad and leave it on the affected area for up to 20 minutes for two days after the injury, and repeat every two hours if you need extra relief. An over-the-counter cream or gel with pain-relieving and anti-inflammatory effects can also help, Dr. Nazareth says. Capsaicin, salicylate cream, or gel—which can be used three to four times a day—might do the trick.
2. Acid Reflux
You know that super uncomfortable squeezing or burning sensation in your left and center chest? That’s acid reflux, and it happens when acid flows from the stomach back into the esophagus, or food pipe, Dr. Nazareth says. Acid reflux can make you feel nauseous, develop a cough, or experience a sour or bitter taste in your mouth. It typically occurs after meals, when you’re stressed, and can feel exacerbated when you’re lying down. It can last anywhere from a few minutes to a couple of hours, Dr. Nazareth adds.
Taking an over-the-counter antacid can help you resolve the issue. Diet changes can also help—like not eating three hours before bedtime and avoiding foods that can make reflux worse—like coffee or caffeinated foods, spicy foods, chocolate, alcohol, peppermint, and fatty foods. Quitting smoking also helps with reflux, says Jayne Morgan, MD, a cardiologist and the clinical director of the Covid Task Force at the Piedmont Healthcare Corporation.
3. Costochondritis
Costochondritis occurs when you have inflammation in the cartilage that joins your ribs to the breastbone (an area is known as the costochondral joint). The pain, which usually affects the lower ribcage, might feel dull and gnawing, and it’ll become more intense if you touch the area, take a deep breath, or cough. It may start on the left side of your chest and spread slowly throughout the rest, per Cleveland Clinic.
It’s not totally clear why some people develop this condition, however, “for some, it might be caused by trauma, heavy lifting, hard exercise, or an illness,” Dr. Nazareth says. The pain typically settles on its own, but if you have costochondritis, you should avoid lifting or pushing heavy things for a few weeks. In the meantime, you can do some stretches to relieve the pain, like the doorway stretch and sphinx pose, and you can also use a heating pad on the area.
4. Tietze Syndrome
This condition is often confused with costochondritis because it’s also identified by inflammation in the costochondral joint. They share almost identical symptoms, but the pain caused by Tietze syndrome is usually felt closer to the shoulder and affects the upper ribcage, per Cleveland Clinic. You’ll also notice chest swelling, which is absent in costochondritis.
Depending on which ribs are affected, you might experience pain when you move or twist your upper body or feel uncomfortable when sitting or lying down in certain positions. Coughing, sneezing, and vomiting may also be more painful than usual. No one really knows what causes this condition—some believe it’s due to small traumas in the chest like straining during exercises, a respiratory infection, or coughing fits, Dr. Morgan says. Tietze syndrome can be treated with rest and OTC anti-inflammatory medications, and it’ll usually resolve fully in one to two weeks, she adds.
5. Pleurisy
If you feel sharp, stabbing chest or shoulder pain when breathing in deeply, there’s a chance it could be a result of pleurisy, which is inflammation of the lining of your lungs (pleura). This occurs when inflammation in your lungs moves into the pleurae and causes them to swell up and rub against each other, per Cleveland Clinic. The pain can accompany a viral infection or result from a chest injury or pneumonia, in which case you would also have a fever and cough, Dr. Nazareth says.
If you have untreated pneumonia, there’s a chance that bacteria from an infection can enter the bloodstream and affect your other organs, so see a doctor ASAP. If the pleurisy is caused by a virus, it might take a couple of days for the pain to go away. But if it’s bacterial pneumonia, the pain will most likely persist until it’s treated, Dr. Nazareth says.
6. Hiatal Hernia
A hiatal hernia—a rarer cause of pain under your left breast—is when your upper stomach bulges through the diaphragm, which separates your abdomen and chest, per Mayo Clinic. The painful sensation might feel like a pulling or tearing from the diaphragm right below the left breast, Dr. Nazareth says.
You might feel this pain when you have increased intra-abdominal pressure, like when lifting weights, groceries, or other heavy objects. It usually lasts as long as you’re doing the movement that is causing the pain. Small hiatal hernias won’t cause any other symptoms, but larger ones could come with heartburn, acid reflux, shortness of breath, feeling full soon after you eat, vomiting blood, and black stools. Talk to your doc if you think you have a hiatal hernia because it generally requires surgical repair, Dr. Morgan says.
7. Pericarditis
Pericarditis is inflammation of the outer lining of the heart, also called the pericardium, Dr. Morgan says. When the swollen and irritated layers of the pericardium rub against each other, chest pain occurs. The duration varies depending on which of the four types of pericarditis you have, and symptoms can include a cough, fatigue, leg swelling, low-grade fever, a racing heart, shortness of breath while lying down, and swelling in your stomach.
Symptoms of pericarditis can overlap with those of other heart and lung conditions, so always consult your doctor if you notice sudden chest pain.
8. Pulmonary Embolism
A pulmonary embolism (PE) is a blood clot in the lung. It’s most common in people who have had a recent surgery, have been on bed rest or sitting for a long time, like on a flight, or have been pregnant, Dr. Nazareth says. The type of pain varies, but it’s usually sharp and stabbing, and comes on suddenly, she says, adding that it gets worse with deep breaths.
The pain might be accompanied by dizziness, fast breathing, shortness of breath, a fast heart rate, coughing (maybe even coughing up blood), and anxiety. A pulmonary embolism can also cause a blood clot in the leg, making it swollen, red, and painful. This disease is potentially life-threatening, so you should book an appointment with your doctor right away if you suspect you have PE.
9. Angina
Angina refers to “pain in the chest or behind the left breast caused by blocked arteries,” Dr. Morgan says. “Angina could be a warning sign of a heart attack.” It generally affects those who have a blockage in their coronary arteries, which are responsible for transporting oxygen to the heart.
You may experience burning, squeezing, dull pain, tightness and pressure, shortness of breath, nausea, and pain going up your left arm, jaw, or back. Physical exertion can cause angina, but it can also stick around even after you cease activity. Regardless of how long it lasts, seek medical attention immediately if you think your discomfort is angina-related, given that it could signal a heart attack.
10. Heart Attack
Pain under your left breast doesn’t necessarily mean you’re having a heart attack, but in some severe cases, it may. If you feel what you would describe as “new” chest pain, involving pressure or discomfort that worsens with activity, there’s a concern that it could be a heart attack, Dr. Nazareth says. You may also feel the same aching in your shoulder, arms, back, neck, and jaw.
Heart attack symptoms can also include trouble breathing and feeling nauseous, sweaty, or lightheaded. The pain may last for more than a few minutes or go away and return, per the CDC. These signs should prompt you to call 911.
When To See A Doctor
If your symptoms aren’t very severe (think: mild discomfort or occasional twinges of pain), schedule an appointment with your healthcare provider within a few days to a week, Dr. Nazareth says. But if your pain is severe, persistent, or accompanied by other concerning symptoms such as shortness of breath, dizziness, nausea, vomiting, or radiating pain to the arm, jaw, or back, seek medical attention ASAP. “If the pain is sudden and severe or persists for more than a few minutes, call emergency services or go to the nearest emergency room immediately,” Dr. Nazareth says.
During the appointment, you can expect a medical history questionnaire and a thorough physical examination. “Your physician may ask questions about the nature and duration of the pain, any exacerbating or alleviating factors, associated symptoms, medical history (including any history of heart disease, gastrointestinal issues, or musculoskeletal problems), medications, and lifestyle factors such as diet, exercise, and stress levels,” Dr. Nazareth says.
Depending on the results of the clinical assessment, your doctor may also order diagnostic tests such as an electrocardiogram (ECG/EKG) to assess heart function, imagine studies such as a chest X-ray, an ultrasound with a mammogram, or blood tests to check for markers of inflammation, infection, or cardiac enzymes, according to Dr. Nazareth. You may be referred to a specialist for further evaluation and management.
Addison Aloian is the Associate Health & Fitness Editor at Women’s Health and a NASM-certified personal trainer (CPT). She writes and edit across the health, weight loss, and fitness verticals. In her free time, you can find her lifting weights at the gym, running on the West Side Highway in New York City, and watching (and critiquing!) the latest movies that have garnered Oscars buzz. In addition to Women’s Health, her work has also appeared in Allure, StyleCaster, L’Officiel USA, V Magazine, VMAN, and more.
Meguire Hennes is a freelance lifestyle journalist specializing in fashion news, celebrity style, dating, and wellness (her Libra moon won’t let her settle on one beat). She received a B.A. in fashion studies from Montclair State University, and her words can be found in Bustle, The Zoe Report, Elite Daily, Byrdie, and more. When she’s not debunking a new TikTok wellness trend or praising Zendaya’s latest red carpet look, you can find her in yoga class, reading a cutesy romance novel, or playing Scrabble with her puppy in her lap.
