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There is a lump
Redness of the skin
Rashes
Nodule with central crusting
Affected area of skin has stinging or tingling
Lump in the breast
Hot skin
Not seeing your symptoms? No worries!
Also called sebaceous cysts, these harmless bumps under the skin are more common in men. They can be caused by skin irritation, injury, or surgery.
Your doctor may ask these questions to check for this disease:
Since they're harmless, they usually don't require treatment. However, a simple surgery can be performed for infected cases or those causing discomfort.
Reviewed By:
Scott Nass, MD, MPA, FAAFP, AAHIVS (Primary Care)
Dr. Nass received dual medical degrees from the David Geffen School of Medicine at UCLA and Charles R. Drew University in Medicine and Science. He completed Family Medicine residency at Ventura County Medical Center with subsequent fellowships at Ventura, University of North Carolina-Chapel Hill, George Washington University, and University of California-Irvine. He holds faculty appointments at Keck School of Medicine of USC, Loma Linda University School of Medicine, and Western University of Health Sciences.
Yukiko Ueda, MD (Dermatology)
Dr. Ueda graduated from the Niigata University School of Medicine and trained at the University of Tokyo Medical School. She is currently a clinical assistant professor at the Department of Dermatology, Jichi Medical University, and holds several posts in the dermatology departments at Kyoto Prefectural University of Medicine, Komagome Hospital, University of Tokyo, and the Medical Center of Japan Red Cross Society.
Content updated on Mar 27, 2025
Following the Medical Content Editorial Policy
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With a free 3-min Epidermoid Cyst quiz, powered by Ubie's AI and doctors, find possible causes of your symptoms.
This questionnaire is customized to your situation and symptoms, including the following personal information:
Biological Sex - helps us provide relevant suggestions for male vs. female conditions.
Age - adjusts our guidance based on any age-related health factors.
History - considers past illnesses, surgeries, family history, and lifestyle choices.
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See full list
Q.
Ingrown Hair Cyst? Why Your Skin Is Swelling & Medical Next Steps
A.
Ingrown hair cysts cause swollen, tender bumps where hair is shaved or rubs; most are minor, but watch for infection signs like worsening pain, warmth, pus, fever, rapid growth, spreading redness, or repeated flares that need medical care. Do not pop it; use warm compresses, gentle exfoliation, pause hair removal, and seek care for drainage, antibiotics, or removal if it persists. There are several factors and look alike conditions to consider; see below for red flags, home care, prevention, and medical next steps.
References:
* Katsoulis IE, Stasinou T, Klonaris C, et al. Pilonidal Disease: An Update on the Management of a Common Condition. Curr Colorectal Cancer Rep. 2021;17(3):141-147. doi:10.1007/s11888-021-00492-4
* Perry PK, Riopelle B, Perry A. Pseudofolliculitis barbae: pathophysiology and treatment. Clin Cosmet Investig Dermatol. 2017;10:391-397. doi:10.2147/CCID.S143003
* Ljubojević S, Lipozenčić J. Folliculitis: update on diagnosis and treatment. Acta Dermatovenerol Croat. 2014;22(4):250-8.
* Mayeaux EJ Jr, Carter C, Pourciau SS, et al. Skin and soft tissue infections. Prim Care. 2014;41(3):613-631. doi:10.1016/j.pop.2014.05.003
* Tayeb T, Saada A, Khoury J, et al. Comparison of Three Surgical Treatments for Chronic Pilonidal Sinus. Med Sci Monit. 2023;29:e939115. doi:10.12659/MSM.939115
Q.
Worried About That Bump? Why Your Skin Is Forming a Dermatofibroma & Medical Next Steps
A.
Dermatofibromas are common, benign, firm skin bumps that often form after minor injury and typically appear on the legs; they are not cancer, but any new or changing lesion should be checked by a clinician, especially if it grows, changes color, becomes painful, or bleeds. There are several factors to consider. See below for the dimple sign, how doctors confirm the diagnosis and rule out look-alikes, when removal is or is not advised and the scarring tradeoffs, what multiple bumps can mean, and which red flags require urgent care.
References:
* Lee YW, Lee JY, Kim CK. Dermatofibroma: an updated review of its pathogenesis and current management strategies. Int J Dermatol. 2019 Dec;58(12):1361-1368. doi: 10.1111/ijd.14605. Epub 2019 Jul 24. PMID: 31339097.
* Ziemer M, Kunte C, Kolb-Mäurer A. Dermatofibroma: an updated clinicopathological and molecular review. J Dtsch Dermatol Ges. 2019 Jun;17(6):629-644. English. doi: 10.1111/ddg.13840. PMID: 31187796.
* Lallas A, Giacomel J, Argenziano G, Zalaudek I, Apalla Z. Dermoscopic features of dermatofibroma: a systematic review. J Am Acad Dermatol. 2014 Feb;70(2):373-9. doi: 10.1016/j.jaad.2013.09.049. Epub 2013 Dec 5. PMID: 24316330.
* Jiang T, Gu X, Cao X, Huang R, Li F, Song Z. Dermatofibroma treatment: A systematic review and meta-analysis. J Cosmet Dermatol. 2021 Nov;20(11):3616-3628. doi: 10.1111/jocd.14502. Epub 2021 Sep 11. PMID: 34508605.
* Calonje E, Mentzel T. The difficult diagnosis of dermatofibrosarcoma protuberans: An update. J Cutan Pathol. 2014 Dec;41(12):879-88. doi: 10.1111/cup.12423. PMID: 25307409.
Q.
Splinter Stuck? Why Your Skin Traps Debris & Medically Approved Removal Steps
A.
Your skin can trap a splinter because inflammation quickly brings blood and white cells, causing swelling that may seal the entry and wall off the foreign object, sometimes lodging it deeper. Safest removal involves washing hands and the area, sterilizing tweezers or a needle, gently pulling the splinter out in the same direction it entered, then cleaning and monitoring for infection; seek care for deep or persistent splinters, spreading redness, fever, eye or under-nail injuries, or if your tetanus is out of date. See below for step-by-step instructions, what not to do, special situations, and other causes that can mimic a splinter.
References:
* Khashab, M. A., & Goldberg, M. J. (2020). Management of Foreign Bodies of the Skin and Soft Tissues. Emergency Medicine Clinics of North America, 38(1), 31-48. pubmed.ncbi.nlm.nih.gov/31733618/
* Gupta, S., & Agrawal, A. (2017). Managing foreign bodies in the skin: a practical approach. Journal of Family Practice, 10(1), 15-18. pubmed.ncbi.nlm.nih.gov/28169460/
* Anderson, J. M., Rodriguez, A., & Chang, D. T. (2016). Host response to biomaterials and medical devices. Seminars in Immunology, 28(5), 427-434. pubmed.ncbi.nlm.nih.gov/27521190/
* Sreerama, S., Sreedharan, R., & Nair, R. (2021). Approach to Foreign Body Injuries in the Emergency Department. Journal of Emergency Trauma and Shock, 14(3), 149-155. pubmed.ncbi.nlm.nih.gov/34663953/
* Pasternack, J., & Lopez, S. J. (2015). Management of soft tissue foreign bodies. Current Sports Medicine Reports, 14(1), 54-59. pubmed.ncbi.nlm.nih.gov/25574345/
Q.
Is That Lump Growing? Why Epidermoid Cysts Form & Medical Next Steps
A.
A smooth, round lump that grows slowly is often an epidermoid cyst, formed when trapped skin cells keep producing keratin inside a sac. These cysts are usually harmless and may stay small for years, though gradual enlargement is common. There are several factors to consider for next steps, including red flags like rapid growth, pain, redness, warmth, drainage, or fever and the advice to avoid squeezing; treatments range from observation or steroid injections to drainage and surgical removal, so see below for key details that can affect when to see a doctor and which option fits you.
References:
* Curylo, L. J., Dammert, L., & Glick, L. R. (2018). Epidermoid Cyst: Clinical Features, Imaging, and Pathogenesis. *Seminars in Diagnostic Pathology, 35*(4), 216-222. https://pubmed.ncbi.nlm.nih.gov/29990847/
* Kumar, P., Yadav, P., Kumar, R., & Singh, R. (2021). Epidermoid Cysts: A Comprehensive Review. *Journal of Clinical & Diagnostic Research, 15*(1), GE01-GE04. https://pubmed.ncbi.nlm.nih.gov/33549666/
* Wang, S. Z., Chen, C., Li, S. T., & Liu, Y. J. (2020). Epidermoid Cysts: Pathogenesis, Clinical Manifestations, and Management. *Clinical Dermatology, 38*(6), 801-807. https://pubmed.ncbi.nlm.nih.gov/33140509/
* Gaskill-Shipley, M. L., White, D. B., & Kim, M. C. (2019). Epidermoid cysts: Clinical and imaging features. *Radiographics, 39*(3), 740-756. https://pubmed.ncbi.nlm.nih.gov/31055743/
* Ko, D., Kwak, D. S., Han, N. H., & Park, S. (2017). Surgical Management of Epidermoid Cysts: A Review of 200 Cases. *Archives of Plastic Surgery, 44*(2), 160-165. https://pubmed.ncbi.nlm.nih.gov/28243615/
Q.
Is it a Sebaceous Cyst? Why your skin is forming a lump and medically approved next steps.
A.
Most skin lumps people call a sebaceous cyst are actually epidermoid cysts, which are usually benign, slow-growing bumps from trapped skin cells or blocked oil glands. They are typically smooth, round, and movable under the skin, sometimes with a small central dot, and are painless unless inflamed. Do not squeeze it; monitor small quiet cysts, use warm compresses for irritation, and seek care for redness, warmth, drainage, fever, rapid growth, firmness, or if you want definitive removal, and see the medically approved next steps and other crucial details below.
References:
* Madan, R., & Sarma, M. (2024). Epidermoid Cyst. In StatPearls [Internet]. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK499818/
* Kashinath, T., & Vora, R. V. (2018). Cutaneous cysts: A review. Journal of the American Academy of Dermatology, 79(6), 1001-1008. https://pubmed.ncbi.nlm.nih.gov/30449216/
* Hassan, S., Hassan, A., Kulkarni, A., & Sarraf, K. M. (2021). Excision of Common Skin Cysts. Plastic and Reconstructive Surgery—Global Open, 9(5), e3590. https://pubmed.ncbi.nlm.nih.gov/34109156/
* Bauer, E. A., & Mann, J. (2017). Common Benign Skin Tumors. Primary Care, 44(4), 629-641. https://pubmed.ncbi.nlm.nih.gov/29126490/
* Shapiro, J. F., & Gilson, K. (2019). Common Dermatologic Procedures: Cysts, Lipomas, and Biopsies. Primary Care, 46(4), 615-628. https://pubmed.ncbi.nlm.nih.gov/31666133/
Q.
Is That Lump a Cyst? Why Your Body Forms Them & Medical Next Steps
A.
A lump could be a cyst, a usually benign sac caused by blocked glands, trapped skin cells, inflammation, injury, hormones, or genetics, with common types like epidermoid, pilar, ganglion, ovarian, and breast cysts. Do not try to pop it; see a clinician urgently for rapid growth, significant pain, redness or fever, a hard or fixed mass, breast changes, or severe pelvic-abdominal pain, since diagnosis is by exam and sometimes imaging and treatment ranges from watchful waiting to drainage or surgical removal; there are several factors to consider, and many more important details below could affect your next steps.
References:
* Batinac T, Batinac P, Batinac K. Cysts and pseudocysts: a review. Acta Clin Croat. 2017 Mar;56(1):175-180. PMID: 28830282.
* Al-Qurayshi H, Bains K. Evaluation of the Solitary Subcutaneous Nodule. Am Fam Physician. 2018 Jan 1;97(1):37-43. PMID: 29363990.
* Khattab A, Samaan D, Khadra A. Diagnosis and treatment of common benign dermatologic lesions. Am Fam Physician. 2020 Jan 1;101(1):29-36. PMID: 31904423.
* Thoma A, Thoma C, Thoma H. Evaluation and Management of Benign Soft Tissue Tumors. Plast Reconstr Surg. 2019 Jul;144(1):185e-195e. PMID: 31259972.
* Handa S, Kumar S, Handa R. Cutaneous Cysts: A Review. J Cutan Aesthet Surg. 2011 Apr-Jun;4(2):140-6. PMID: 21966144.
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https://www.medrxiv.org/content/10.1101/2024.08.29.24312810v1Maeda T, Mishima K, Imanishi J, Shirahata M, Suzuki T, Adachi JI, Sasaki A, Nishikawa R. An Epidermoid Cyst of the Thoracic Spine in an Elderly Patient. World Neurosurg. 2019 Jul;127:113-116. doi: 10.1016/j.wneu.2019.03.262. Epub 2019 Apr 2. PMID: 30951916.
https://www.sciencedirect.com/science/article/abs/pii/S1878875019309428?via%3DihubKhalid S, Khan SA, Aurangzeb A, Muhammad G, Khan Afridi EA, Muhammad D. Intradiploic Epidermoid Cyst Of The Skull. J Ayub Med Coll Abbottabad. 2021 Apr-Jun;33(2):349-351. PMID: 34137560.
https://jamc.ayubmed.edu.pk/jamc/index.php/jamc/article/view/9211/3122Sîrbu OM, Chirteş AV, Mitricã M, Sîrbu CA. Spinal Intramedullary Epidermoid Cyst: Case Report and Updated Literature Review. World Neurosurg. 2020 Jul;139:39-50. doi: 10.1016/j.wneu.2020.03.207. Epub 2020 Apr 13. PMID: 32298825.
https://www.sciencedirect.com/science/article/abs/pii/S1878875020306781?via%3DihubCui X, Wu X, Yao X. Surgical treatment for a giant epidermoid cyst on the buttock. Dermatol Ther. 2020 May;33(3):e13275. doi: 10.1111/dth.13275. Epub 2020 Feb 21. PMID: 32061013.
https://onlinelibrary.wiley.com/doi/10.1111/dth.13275