Acne – Diagnosis, Symptoms, and Treatment

Doctor Nathan LeDeaux, MD

Medically reviewed by Dr. Nathan LeDeaux, MD

Medical Professional

Updated - December 14, 2020

Nathan LeDeaux is an emergency medicine physician at the University of Wisconsin and got his M.D. from Northwestern University in Chicago Illinois.

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What is Acne?

Acne is a medical condition characterized by inflammation of the pores in the skin.  The most commonly affected areas include the forehead, cheeks, chest, and back. Acne is most common in adolescent males and females due to increased levels of hormones known as androgens.  It may also occur in patients with other underlying diseases that increase the levels of androgens such as polycystic ovarian syndrome of those that use certain medications, such as those used for infertility treatmentAcne rarely leads to serious medical harm but can be extremely distressing as it results in a change in appearance. Often during the teenage years, which is an extremely vulnerable time in most patient’s lives. 

While the majority of acne is mild and resolves with minimal treatment some forms can be painful and disabling. In these rare cases, lifelong treatment or specialized medications will need to be started by a dermatologist. 

What Causes Acne?

Acne is caused by both genetic and environmental factors. Hormonal changes, the usage of skin products, the moisture levels of the skin, the natural bacteria that live on the skin, and hormonal changes all play a major role. Patients typically develop red irritating bumps on the face and other regions due to the overgrowth of bacteria that normally live on the skin without issues. These bacteria multiply rapidly in the pores which leads to inflammation and the characteristic red raised bumps that define acne. The most common bacteria that leads to acne is Propionibacterium acnes.

Acne begins when the pores fill get plugged with dead skin debris and skin oils known as sebum. This leads to bacteria getting trapped in the pores and allows for it to grow rapidly – which promotes skin irritation and inflammation.  This results in small areas of redness and swelling frequently referred to as “pimples.”  Patients may also develop comedones, which is the medical term for “blackheads.”  These result from more chronic blockages of the pores that do not become infected and instead continue to accumulate more oils and dead skin debris. 

How Common is Acne?

Acne is extremely common in the United States, estimates on acne prevalence vary widely with up to 90% of adolescents reporting acne and physicians estimating that 30% of their patients would benefit from medical treatment of acne. 

Acne usually begins in the teenage years and self resolves by the age of 30. This age-related onset is thought to be due to puberty increasing the amount of sex hormones, known as androgens, within the body. In some cases, acne persists after puberty but this is less common, leading to lower rates of acne within the adult population. Acne is more likely to persist after puberty in women due to the higher levels of androgens within their bodies.

Signs and Symptoms

Symptoms and signs of acne typically include red, painful, and swollen bumps on the face, back, or chest.  These skin lesions are known as pustules, which means that they contain a small amount of pus which is made up of dead bacteria and immune cells. Sometimes these small pustules grow in size in which case they are called cysts. These cysts can ultimately lead to severe scarring and deformation of the skin. In extreme cases, these cysts can become infected with other bacteria than the ones that cause acne. Leading to increased pain, redness, and swelling. If areas of acne have redness that spreads a significant distance from the bumps on the skin, is painful when moving the face or eating, or result in fever. Antibiotics will likely be needed to control the infection. 


The diagnosis is made based on your recollection of when the lesions on the skin presented, a review of your medical history, and an examination of the skin.  There are no tests that your doctor needs to order to confirm the diagnosis.  In severe cases that are unresponsive to first-line treatment, your doctor may refer you to a dermatologist for specialized treatment.  In these cases, they may biopsy the skin lesions or send pus for gram stain and culture to reveal which bacteria are causing the infection.

Acne may be a sign of several severe conditions, each of these conditions causes acne by increasing the number of androgens in the body. In women, this increase in androgens is associated with symptoms such as hair growth on the upper lip, chin, and chest. Women with these signs in addition to acne should be evaluated for conditions such as polycystic ovarian syndrome, ovarian cancer, adrenal cancer, and other conditions related to the adrenal glands. 

Acne Treatment and Medication

The treatment of acne begins with medications that are placed on the skin, known as topical medications. If these do not result in a dramatic improvement oral antibiotics are generally added to help kill off the bacteria that lead to acne. If both of these treatments fail hormonal treatments or treatment with oral isotretinoin (Accutane) may be started. This path through the options to treat acne is done to minimize any complications of treatment by starting with the medications that are the least likely to cause side effects.

The topical medications are generally very well tolerated with minimal side effects and excellent results in the majority of patients. They are most effective for more mild forms of acne, severe cystic acne will likely require additional treatments. 

Topical medications are often combined with topical antibiotics, which have fewer side effects than their oral counterparts. Acnegon (clindamycin) and Eryacne (erythromycin) are two of the most common medications prescribed. Studies show that the combination of benzoyl peroxide and a topical antibiotic is more effective than either agent alone.

In more severe cases of acne, a topical retinoid, topical benzoyl peroxide, and an oral antibiotic are typically prescribed as a combination treatment.  Oral antibiotics are most commonly used for up to 3-4 months with the goal of eliminating the bacteria on the skin that contribute to acne.  Commonly prescribed oral antibiotics include:

Patients with very severe acne not responsive to these measures may require Accutane (oral isotretinoin). Accutane has several severe potential side effects, the most common being severe birth defects in pregnant women. For this reason, Accutane also requires the use of hormonal birth control which has its own side effects. 

Hormonal therapy is an additional therapeutic option in women with moderate to severe acne.  It is often used in combination with topical retinoids and antimicrobial agents.  These typically include Aldactone (spironolactone) and oral contraceptives.  Commonly prescribed contraceptives include:

  • Ortho Tri-Cyclen - estrogen combined with norgestimate
  • YAZ - estrogen combined with drospirenone
  • Estrostep - estrogen combined with norethindrone

At times these medications may be started even before topical medications. Women that wish to use hormonal birth control medications for the primary purpose of pregnancy prevention may also see an improvement in their acne. 


  1. Dalgard F, Gieler U, Holm JØ, et al. Self-esteem and body satisfaction among late adolescents with acne: results from a population survey. J Am Acad Dermatol 2008; 59:746. -
  2. Haider A, Shaw JC. Treatment of acne vulgaris. JAMA 2004; 292:726. -


The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.