Why Does My Acne Stink? Causes & Treatment

Medically Reviewed on 11/10/2022
Why Does My Acne Stink
Learn about what factors can contribute to smelly acne and when it is cause for concern

Smelly acne can be due to dead bacteria, white blood cells, and other necrotic material in the pus or sebum that produces a foul odor.

Learn about what factors can contribute to smelly acne and when it is cause for concern.

What factors can contribute to smelly acne?

  • Bacteria type: Various types of bacteria can infest the skin, resulting in clogged pores and acne. Both aerobic bacteria (bacteria that require oxygen to grow) and anaerobic bacteria may cause a foul smell in your acne discharge.
  • Acne severity: Mild acne generally does not produce a strong smell. Moderate to severe acne with pus discharge, however, may be more likely to have a bad smell.
  • Poor hygiene: If you do not keep the area around the acne clean, you are more likely to contract secondary infections from the bacteria. More severe infections result in acne pus that has a stronger odor. Keeping the site clean, therefore, is critical.
  • Acne discharge: Acne pus is made up of dead white blood cells that fight invading bacteria. The drainage, which includes pus mixed with blood, debris, and bacteria, oozes out when acne is punctured. The more the contents in the acne, the more it may smell.

Is smelly acne a cause for concern?

Although severely infected skin may be a cause for concern, smelly acne is usually not a serious condition. However, the smell of acne may indicate an infection or underlying health condition.

Smells like cheese

  • Cause: If you have acne that has a discharge that smells like cheese, you most likely have an epidermoid cyst, a noncancerous bump under your skin. An epidermoid cyst develops when dead skin cells accumulate deep in the skin and don't slough off as they should. An injury or irritant may also cause epidermoid cysts to form. These cysts typically consist of a thick, yellow substance made of the protein keratin that has a cheesy texture.
  • Treatment: Although epidermoid cysts are typically painless, they can occasionally become inflamed or infected and rarely even develop into skin cancer. Visit your dermatologist if the cyst turns red, swollen, or painful. Your dermatologist may decide to treat you with anti-inflammatory injections, drain the cyst or remove it completely.

Smells like rotten eggs

  • Cause: Acne conglobata, a rare form of nodulocystic acne that develops when painful, large cysts connect deep beneath the skin, can have pus with a rotten egg-like smell. Acne conglobata is a severe skin condition and a common symptom is multiple inflamed nodules filled with pus that may smell like rotten eggs.
  • Treatment: Visit a dermatologist to treat this severe form of acne. Retinoids, steroids, or antibiotics may be recommended by your doctor to help manage the symptoms.

Smells like onions or garlic

  • Cause: Acne lesions are filled with dead white blood cells that feed the bacterial infestation. Because most of these bacteria are anaerobic, they produce their own sulfur compounds as they grow. These sulfur-containing compounds can cause a pungent smell of garlic or onions when you pop the acne.
  • Treatment: Visit a dermatologist for prescription-strength acne treatments.


Skin Health: How to Get Clear Skin See Slideshow

What are the grades of acne?

Severe acne causes cysts and nodules, which are breakouts that extend deep into the skin. These breakouts are usually painful and can remain on your skin for weeks or months. Severe acne is generally classified as grade III or IV.

Understanding the severity of your acne can help you determine whether you can treat your acne at home or if you should see a dermatologist:

Acne grades are as follows:

Grade I

  • Mildest type of acne. 
  • There may be a few tiny pimples, but they will be few, sporadic, and infrequent (1-2 every once in a while). 
  • There may be no swelling, but blackheads can occasionally be found in large numbers, especially in the nose and/or forehead.
  • Grade 1 acne can be successfully treated at home with salicylic acid-containing over-the-counter products

Grade II

  • Moderate type of acne.
  • In general, blackheads will be more prevalent, more papules will appear, and pustules will begin to form. 
  • Acne occurs more frequently, and general breakout activity will be more noticeable. The skin may be slightly swollen. 
  • Acne may spread from the forehead and nose to other facial regions. 
  • Women may experience increased breakout activity along their jawline, chin, and cheeks, particularly before and during the menstrual cycle.
  • Grade II can be treated at home with over-the-counter medications. To help kill bacteria that cause inflamed breakouts, benzoyl peroxide lotion can be used in addition to salicylic acid. 

Grade III

  • Severe type of acne.
  • Skin is clearly inflamed and reddened. 
  • There may be nodules and more papules and pustules than usual. 
  • Grade III typically affects the face in addition to other body parts such as the neck, chest, shoulders, and/or upper back. 
  • As the infection deepens and spreads, the likelihood of scarring increases.
  • At this point, acne should be treated by a dermatologist. Treatment of grade III acne typically includes both topical and systemic approaches, such as prescription-only antibiotics. 

Grade IV

  • Most severe type of acne and often referred to as cystic acne
  • In addition to cysts, the skin will show numerous papules, pustules, and nodules. 
  • The swelling is noticeable, and the breakouts are severe and may be painful.
  • The majority of people with severe acne have acne on their entire back, chest, shoulders, and upper arms. 
  • The infection is severe and pervasive and typically causes scarring.
  • Dermatologists treat acne of grade IV by recommending prescription-strength topical systemic medications.

Although it may be tempting, avoid popping or squeezing pimples, as this can push bacteria deeper into the skin. If you pop a smelly pimple and the drainage oozes out, the invading bacteria will enter other pores and result in acne. Therefore, it is crucial to wipe off any pus that has oozed out of acne to stop further bacterial growth and infection. Squeezing can also result in scabs and pits or scars that won't go away.

Medically Reviewed on 11/10/2022
Image Source: iStock image

Acne Conglobata: https://www.ncbi.nlm.nih.gov/books/NBK459219/#:

Epidermoid Cyst, No Infection: https://www.fairview.org/Patient-Education/Articles/English/e/p/i/d/e/Epidermoid_Cyst_No_Infection_116519en

Acne Treatments That Work: https://www.webmd.com/skin-problems-and-treatments/acne/acne-treatments-that-work