Breast pain: Causes and when to worry — Pain Pattern Guide

💚 Good news: Breast pain (mastalgia) is very common, affecting approximately 70% of women at some point in their lives — and 90% of breast pain is not cancerous. Most breast cancers are not painful in their early stages. The most common causes are cyclical mastalgia (pain related to menstruation), fibrocystic changes, costochondritis (pain in the rib cartilage), or side effects from certain medications. However, persistent breast pain, localized pain, unilateral pain unrelated to menstruation, or pain accompanied by a lump, skin changes, or nipple discharge should be discussed with a breast specialist for peace of mind and safety.

How common is breast pain?

Breast pain is one of the most common health problems that brings women to see a breast specialist — but most are harmless.

Important information that women should know:

• 70% of women experience breast pain at some point in their lives.

• 90% of breast pain is not caused by cancer.

• Early-stage breast cancer is mostly painless — only 5-15% of breast cancer patients experience pain as an initial symptom.

• Cyclical mastalgia (menstrual pain) is the most common, accounting for two-thirds of all breast pain.

• Most common age range — 30-50 years (reproductive years).

Three main types of breast pain — how to differentiate them.

Classifying breast pain helps doctors diagnose and treat it accurately.

1. Cyclical Mastalgia (menstrual pain)

nature:

• Pain before or during menstruation.

• Pain on both sides (Bilateral)

• The breasts are painful, swollen, tight, and heavy all over.

• Severe pain in the upper outer quadrant (upper outer part of the breast).

• Better after menstruation ends.

• Mostly in women aged 30-45 years.

cause:

This is caused by changes in the hormones estrogen and progesterone, which stimulate breast tissue.

2. Non-Cyclical Mastalgia (Pain not related to menstruation)

nature:

• The pain is not related to my menstrual cycle.

• Usually pain is on only one side (unilateral).

• Localized pain

• Is the pain sharp or stinging?

• Is it continuous or intermittent?

• Mostly found in women aged 40-50, or those going through menopause.

Common causes:

• Cyst (breast cyst)

• Severe fibrocystic changes

• Trauma or injury.

• Post-surgical pain

• Mastitis, or inflammation

• Mondor's Disease (Superficial thrombophlebitis)

• Duct Ectasia

3. Extramammary Pain (Pain outside the breast)

nature:

• The pain is in the breast area, but it's not actually coming from the breast tissue.

• The pain is usually localized and the exact location can be felt.

• The pain worsens when the area is moved or pressed.

• It is not related to the menstrual cycle.

Common causes:

• Costochondritis (Tietze Syndrome) — Pain in the cartilage of the rib joints and sternum.

• Muscle strain — Inflammation of the chest muscles from exercise.

• Nerve pain — from the thoracic spine or intercostal nerve.

• Shingles (Herpes Zoster) — Painful rash that appears in patches.

• Cardiac pain — Angina/Heart attack — may cause pain to radiate to the left chest.

• GERD — Acid reflux causes chest pain.

Common causes of breast pain — details.

Hormonal Changes

• Premenstrual syndrome (PMS) — High estrogen levels.

• Pregnancy — especially the first 3 months.

• Adolescence (Puberty) — Breasts are developing.

• Perimenopause — Hormone fluctuations.

Medications (that cause breast pain)

• Hormone medications — Birth Control Pills, Hormone Replacement Therapy

• Tamoxifen — especially during the first 3-6 months.

• Antidepressants (SSRIs) — Fluoxetine, Sertraline

• Diuretics (Spironolactone)

• Cardiovascular medicines —Digoxin, Methyldopa.

• Anabolic Steroids

Read more: Tamoxifen side effects

Lifestyle Factors

• The bra doesn't fit properly — it's too tight or doesn't provide enough support for the breasts.

• Exercising intensely — without wearing a sports bra.

• Caffeine — Coffee, Tea, Chocolate, Soda

• stress

• Smoking

• High-fat diet

Pathologic Causes

• Cyst — A fluid-filled sac in the breast, especially if it is large or inflamed.

• Mastitis — Inflammation of the breast due to infection.

• Breast Abscess — Abscess in the breast

• Duct Ectasia — Enlargement and inflammation of the milk ducts.

• Fat necrosis — Localized death of adipose tissue.

• Mondor's Disease — Thrombophlebitis of the subcutaneous veins of the breast.

💚 Don't worry too much about any type of breast pain.

Breast pain that is unlikely to be serious — but you should still consult a doctor if it interferes with your daily life.

• Pain on both sides — symmetrical.

• Pain before or during menstruation — that improves after menstruation ends.

• Pain that is swollen and tight — throughout the breast, not just in one spot.

• No palpable lumps.

• There were no changes to the skin or nipples.

• There is no lymphatic fluid from the nipple.

• Age < 30 years and no family history of cancer.

⚠️ What types of breast pain require a doctor's visit?

Characteristics of breast pain that require evaluation by a specialist.

🟠 See a doctor within 1-2 weeks.

• Unilateral pain, localized, persistent for more than 2 weeks.

• Pain that is not related to menstruation and is persistent.

• Pain accompanied by a palpable lump.

• Pain accompanied by pus/blood discharge from the nipple.

• The pain is severe and disrupts daily life.

• Pain that hasn't improved after menopause for 3 months.

🚨 Go to the ER immediately.

• Breast pain accompanied by redness, swelling, and warmth, rapidly progressing — may be IBC or Severe Mastitis.

• Chest pain radiating to the left arm/chin/back + nausea + sweating — may be a heart attack.

• Sudden chest pain + difficulty breathing — may be a pulmonary embolism.

• Severe pain immediately after an injury.

• Breast pain accompanied by a high fever (> 39°C)

Read more: Red, dimpling, and orange peel-like skin on the breast — Signs of Inflammatory Breast Cancer

Pain Pattern Decision Tree — Self-assessment possible

This tool helps you assess how concerning your breast pain is — answer the questions in order.

❓ Question 1: How many sides are hurting?

• Both sides → Go to question 2.

• One-sided → Go to question 3.

❓ Question 2: Is pain related to menstruation?

• Pain before/during menstruation, improves after menstruation → 🟢 Cyclical Mastalgia · Not dangerous · Try adjusting your lifestyle.

• Not related to menstruation → 🟡 Non-Cyclical · Consult a doctor within 2-4 weeks.

❓ Question 3: Can you feel any lumps or changes?

• Lump / Skin change / Lymphatic fluid discharge from nipple → 🟠 See a doctor within 1 week.

• No — it just hurts → Go to question 4.

❓ Question 4: Is the pain localized or widespread throughout the breast?

• Localized pain, palpable location → Consult a doctor within 2 weeks — may be a cyst or costochondritis.

• Pain spreading → Try lifestyle modifications for 1 month — if it doesn't improve, see a doctor.

🚨 Seek immediate medical attention if you experience any of the following symptoms:

• Breast redness, swelling, and heat, rapidly.

• Chest pain radiating to the arms/neck/back + sweating + nausea.

• Sudden, severe pain with no known cause.

• High fever + breast tenderness + lump

Treatment and relief of breast pain.

1. Lifestyle Modifications (First Measure)

• Wear a well-fitting bra — Supportive Bra · Correct size · Try measuring again.

• Sports bra for exercising.

• Reduce caffeine intake — coffee, tea, chocolate, soda (cut by half in the first 2 months).

• Reduce high-fat foods — focus on the Mediterranean diet.

• Exercise regularly — 30 minutes, 5 days/week.

• Stress management — Yoga, Meditation, Deep breathing

• Avoid smoking.

2. Heat/Cold Therapy

• Warm compression — Helps stimulate circulation. Used for chronic pain.

• Cold compression — Reduces swelling and inflammation. Use in cases of acute pain.

• Cabbage leaves — some people find them helpful during breastfeeding.

3. Over-the-Counter Medications

• Paracetamol — 500-1000 mg every 6 hours. Safe.

• NSAIDs — Ibuprofen, Naproxen — Reduce inflammation + relieve pain.

• Topical NSAIDs Gel — Diclofenac gel: Apply to the painful area.

4. Supplements (with medical evidence)

• Evening Primrose Oil — 1,000-3,000 mg/day · Evidence suggests it may help reduce cyclical mastalgia.

• Vitamin E — 200-400 IU/day

• Vitamin B6 — 100 mg/day

• Magnesium — 200-400 mg/day

• Omega-3 — 1,000-2,000 mg/day

⚠️ Consult your doctor before starting supplements, especially if you are taking regular medication.

5. Prescription Medications (under the guidance of a physician)

• Tamoxifen — for severe cyclical mastalgia that does not respond to other treatments.

• Danazol — Treats severe mastitis. Use when necessary.

• Bromocriptine — Reduces prolactin levels; used in some cases.

6. Treatment tailored to the specific cause.

• Cyst — Aspiration (draining fluid) if it's large and painful.

• Mastitis — Antibiotics (Cloxacillin, Augmentin)

• Costochondritis — NSAIDs + Local injection if necessary.

• Muscle strain — Physical therapy + Rest

• Shingles — Take an antiviral medication (acyclovir) within 72 hours of the rash appearing.

Breast pain from Tamoxifen — Side effects you should know.

Patients being treated with Tamoxifen may experience breast pain, especially in the first 3-6 months — this is common.

Symptoms:

• Both sides hurt.

• Painful, swollen, and tight.

• The most severe symptoms occur in months 1-3.

• Gradually getting better after 6 months.

How to handle it:

• Use paracetamol or NSAIDs.

• Supportive Bra

• Evening Primrose Oil

• Reduce Caffeine

• Report to your doctor if the condition is severe or does not improve.

⚠️ Do not stop taking Tamoxifen on your own without consulting a doctor.

Breast pain during pregnancy and breastfeeding.

During pregnancy.

Breast tenderness is one of the first symptoms of pregnancy in many women — it's caused by changes in the hormones estrogen and progesterone that stimulate breast development in preparation for breastfeeding.

• Pain with swelling and tightness on both sides.

• Most severe in the first 3 months.

• Improved in the second and third quarters.

• A supportive bra can help.

During breastfeeding.

Breast pain during breastfeeding may be caused by:

• Engorgement — The breasts are full of milk. Relieve this by breastfeeding more frequently.

• Plugged Duct — Blocked milk duct. Massage + warm compress + continue breastfeeding.

• Mastitis — Inflammation of the breast · Requires antibiotics.

• Sore nipples — from improper breastfeeding position. Consult a Lactation Consultant.

• Candida Infection (Thrush) — Fungal infection of the nipples. Use an antifungal agent.

⚠️ In breastfeeding women — if mastitis does not improve within 1-2 weeks after treatment with antibiotics, a skin biopsy is required to isolate IBCs (Intracytoplasmic Sclerosis).

Breast pain assessment at Numarak Hospital.

As a specialized breast disease hospital, we understand that breast pain often comes with concern, even though most cases are harmless.

Breast pain assessment service.

• Clinical examination by 5 breast surgeons — Fellowship-trained team.

• Hologic 3D Mammography + Genius AI for women aged ≥ 40 years.

• Breast ultrasound for women under 40 years old, or as a supplement with mammogram.

• Cyst aspiration in the examination room if necessary.

• A pain management plan designed based on the cause and severity of the pain.

• Lifestyle Counseling — Nutrition, Wearing Bras, Exercise

• Multidisciplinary referral — Cardiologist, Orthopedist if Extramammary pain

High Tech, High Touch philosophy for warm care.

At Namarak Hospital, "it's like visiting a friend's house" —meaning we don't leave patients worrying alone. Even if test results are normal, we'll explain things clearly, plan appropriate follow-up, and give them the confidence to return to their normal lives.

Frequently Asked Questions (FAQ)

Does breast pain mean it's cancer?

In most cases, no—90% of breast pain is not caused by cancer. Interestingly, most early-stage breast cancers are painless—only 5-15% of breast cancer patients experience pain as an initial symptom. Therefore, breast pain is not a direct sign of cancer, but a painful lump should still be evaluated.

Is pain in only one breast dangerous?

Depending on other factors, unilateral pain caused by cysts, costochondritis, or Mondor's disease is usually harmless. However, unilateral pain with a mass, skin changes, or that persists for more than two weeks should prompt a consultation with a doctor. Non-cyclical mastalgia requires more evaluation than cyclical bilateral pain.

Is breast tenderness after menopause normal?

It can occur during perimenopause and menopause—hormones continue to fluctuate and may cause breast tenderness, especially if hormone replacement therapy (HRT) is used. However, breast tenderness in postmenopausal women requires more investigation than in women of reproductive age because the risk of cancer is higher.

Is breast pain during intercourse normal?

Normally, breasts become more sensitive to touch during sexual arousal and may become tender, especially before or during menstruation. If the pain is unusually severe or persistently localized, you should consult a doctor to determine the cause.

Why is caffeine levels low in breast pain?

Caffeine and methylxanthines (found in coffee, tea, chocolate, and soda) may stimulate fibrocystic changes and worsen breast pain in sensitive women. Research has found that reducing caffeine intake by half for two months reduced symptoms in approximately 60-70% of patients.

Should I get a mammogram if I have breast pain?

Depending on age and symptoms, women ≥ 40 with persistent breast pain, especially on one side or unrelated to menstruation, should have a mammogram to ensure there are no hidden lumps. For women < 40, ultrasound is the first choice.

Is breast pain from exercise something to worry about?

Not necessarily — soreness that occurs after strenuous exercise, especially that focuses on the chest muscles (push-ups, bench press, some yoga poses), is often a muscle strain of the pectoralis muscle. This can be relieved with rest, NSAIDs, and a good sports bra. If it doesn't improve within 1-2 weeks, consult a doctor.

Breast pain accompanied by sweating and nausea: Is this a sign of a heart attack?

Yes — especially in women over 40 with risk factors (diabetes, hypertension, high cholesterol, smoking, family history) — left chest pain accompanied by sweating, nausea, and shortness of breath could be a heart attack. In women, the pain doesn't necessarily have to be the classical 'heaviness in the chest' — and immediate ER work is necessary.

Consult a breast specialist at Numarak Hospital.

If you experience persistent breast pain or want to get a checkup to be sure, our medical team is ready to assess and advise you:

• Tel: 02-059-0245

• LINE: @namarak (page.line.me/vfg3683z)

• Book an appointment online.

• Request a second opinion.

• Breast specialist team

Read more

• If I find a lump in my breast, is it cancerous?

• Red, dimpling, orange peel-like skin on the breast — Inflammatory Breast Cancer

• Tamoxifen side effects

• 3D Mammogram + Hologic Genius 3D AI

• What is DCIS? Stage 0 breast cancer.

• ESMO Breast 2026 — A new direction in breast cancer treatment.

About the editor.

Assoc. Prof. Yaowanuch Kongdan , M.D., Breast Surgeon + Surgical Oncologist · Founder and Director of Namarak Hospital · President of the Thai Breast Disease Society (TBS)

Note: This article is for general information only and cannot replace diagnosis and advice from a specialist. If you have any worrisome breast pain, you should consult a doctor for a direct evaluation, especially if the pain is unilateral, persistent, or accompanied by other symptoms.

References

• ACS Breast Cancer Facts & Figures 2025-2026

• NCCN Clinical Practice Guidelines—Breast Pain Evaluation

• Mansel RE et al. Mastalgia (Breast Pain). BMJ Clinical Evidence 2014

• Ader DN, Browne MW. Prevalence and impact of cyclic mastalgia. American Journal of OB-GYN 1997

• Pruthi S et al. Vitamin E and Evening Primrose Oil for Cyclic Mastalgia. Alt Med Rev 2010