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What is Acne? Types, Causes & Treatments

Kristin Hall

Medically reviewed by Kristin Hall, FNP

Written by Our Editorial Team

Last updated 5/3/2021

Are you going through an acne breakout? Dealing with an acne breakout can be an immensely frustrating experience, especially when your acne develops unexpectedly and doesn’t seem to go away. 

Acne is one of the most common skin conditions. In fact, research has found that it’s essentially universal, with 79 to 97 percent of people dealing with acne during adolescence.

Even in adulthood, acne is very common, with between 40 percent and 54 percent of people above the age of 25 affected by acne breakouts.

If you’re struggling with acne, it’s important to understand that real, proven options are available to help you clear your skin and prevent breakouts from coming back. 

Below, we’ve explained what acne is, the most common types of acne and the main factors that may cause you to develop acne throughout your life.

We’ve also explained how you can treat breakouts and prevent acne from coming back using a mix of over-the-counter products, prescription medications and skin-friendly habits.

Types of Acne

Acne can vary in type and severity. While some types of acne are usually mild and easy to treat with over-the-counter products, others can be painful and challenging to get rid of. 

Dermatologists often classify acne as either mild, moderate or severe based on the number and type of acne lesions you have. 

Below, we’ve explained the different acne severity levels, as well as the specific characteristics that define mild, moderate and severe forms of this common skin condition. 

We’ve also listed the most common types of acne lesions, from whiteheads and blackheads to pustules, nodules and other forms of inflamed acne.

Mild Acne

Mild acne is, as its name suggests, acne that’s mild in nature. The Adult Female Acne Scoring Tool (AFAST) defines mild acne as acne that affects less than half of your face and is made up of comedones, papules and pustules.

If you have mild acne, you may occasionally get whiteheads, blackheads and inflamed types of acne that affect your face. These develop due to a variety of factors, including the oil produced by your skin and accumulation of dead cells on your skin’s surface. 

Most of the time, dermatologists treat this type of acne using topical products that are available over the counter. 

Moderate Acne

Moderate acne is more severe than mild acne. It may affect more than half of your face and be made up of lots of papules, pustules and comedonal acne lesions. If you have moderate acne, you may also develop up to one nodular acne lesion at a time.

We’ve provided more information on exactly what nodules, papules and other acne lesions are in the section below. 

This type of acne is more challenging to treat than mild acne. A dermatologist may prescribe a topical retinoid and/or antibiotic in combination with products available over the counter.

Severe Acne

Severe acne is obvious and challenging to treat. This type of acne may cover your entire face and include a large number of papules, pustules and comedonal acne lesions, as well as rare nodules.

In some cases, acne is defined as “very severe” in nature. A dermatologist will usually define acne this way when you have highly inflammatory acne lesions, including lots of nodules, that affect your entire face.

Severe acne is the most challenging type of acne to treat. Dermatologists often recommend a combination of products, including the prescription medication isotretinoin, to treat this type of acne.

Hormonal Acne

Hormonal acne is any acne that develops as a result of fluctuations in your body’s production of certain hormones. 

You may notice hormonal acne developing just before and during your period, when your levels of certain hormones are higher than normal. This type of acne is common in women with health issues that affect hormone production, such as polycystic ovary syndrome (PCOS).

Hormonal acne can vary hugely in severity. While some people may only develop a few pimples during their period (or even no acne at all), others might get moderate or severe acne. 


Whiteheads are small, non-inflammatory acne lesions, meaning they aren’t affected by bacterial growth. These form when the pores in your skin become clogged with a combination of oils from your sebaceous glands (referred to as sebum) and debris on your skin’s surface. 

Many people refer to whiteheads as closed comedones, or simply “pimples.” These lesions are very common and can develop all over your face and body. 

As a mild form of acne, whiteheads are usually easy to treat with over-the-counter products and acne medications.


Blackheads are non-inflammatory acne lesions that have a dark surface. Similar to whiteheads, blackheads develop when your pores become clogged due to a combination of sebum and skin cells that can accumulate on your skin’s surface and inside your hair follicles.

While whiteheads are referred to as closed comedones, blackheads are sometimes referred to as open comedones. This is because blackheads have dilated openings that allow air to come into contact with the debris blocking the follicle.

Our guide to the differences between whiteheads and blackheads explains these differences in more detail.

Contrary to popular belief, the dark brown-black color of a blackhead isn’t caused by dirt or poor hygiene. Instead, it develops when the contents of the hair follicle react with oxygen.

Like whiteheads, blackheads are typically easy to treat with over-the-counter products and acne medications. 


Papules are small inflammatory acne lesions that are often red and tender. They develop when bacteria, such as Propionibacterium acnes, or P. acnes, multiply inside a clogged pore, causing it to become inflamed and irritated.

Many people refer to papules simply as “pimples.” This type of acne is common and can affect your face and body. 

Unlike more severe forms of acne, papules are usually quite small. When touched, this type of acne can feel firm. When lots of papules develop in a small area of your skin, they can give the skin a rough, sandpaper-like texture.

Papules tend to be more challenging to treat than whiteheads and blackheads and may require products to control bacterial growth on your skin.


Pustules are small, red acne lesions that are similar in size and appearance to papules, except that they contain yellow fluid.

The fluid inside pustules gives this form of acne a yellow-white color that can stand out against your skin. Pustules are sometimes referred to as “pus bumps” or by common umbrella terms for acne such as “pimples” or “zits.”

Nodular Acne (Nodules)

Nodular acne is a more severe form of acne that develops when papules and pustules grow in size and form deeper in your skin.

Like other forms of inflammatory acne, nodular acne forms when bacteria multiply inside a pore that’s blocked due to sebum and dead skin cells. 

Acne nodules can be firm, uncomfortable and painful. This type of acne is larger than pustules or papules and can leave behind permanent scarring, especially when it’s picked at, popped or treated without proper care.

Treating nodular acne is often challenging and often requires the use of several medications to prevent clogged pores and control bacterial growth. 

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Cystic Acne (Cysts)

Cystic acne, or nodulocystic acne, is a very severe form of acne that involves large, fluid-filled acne lesions, called cysts, that develop deep within your skin.

This type of acne can be painful and uncomfortable. You may develop one or several cysts on your face or other parts of your body that are red, swollen and large enough to have a severe, obvious impact on your appearance.

Like nodular acne, breakouts of cystic acne have the potential to leave behind acne scars that affect your face and body. Although this type of acne is severe, it’s usually treatable with one or several acne medications. 

If you have cystic acne, it’s important to contact a dermatologist and start treating it as early as possible to prevent permanent scarring from developing. 

Fungal Acne

Pityrosporum folliculitis, or fungal acne, is a type of fungal infection that can cause symptoms similar to acne, such as papules and pustules that develop on the face, chest, back and other parts of the body. 

Because this type of “acne” is caused by fungi rather than sebum, dead skin cells and bacteria, regular acne treatments aren’t effective at clearing it. 

In fact, some antibiotics that are commonly used to treat acne can make the fungi that causes pityrosporum folliculitis grow faster, worsening this type of infection.  

This type of infection is common in adolescents and is often misdiagnosed as acne. It’s best treated using oral antifungal medications, or, when it occurs in combination with regular acne, both antifungals and conventional acne medications.

Risk Factors & Causes of Acne

Acne develops when the pores, or hair follicles, in your skin become clogged with a combination of sebum and dead skin cells.

Sebum is a type of oil that’s secreted from your sebaceous glands. When it’s secreted in normal amounts, sebum plays an essential role in helping your skin to retain moisture and protect itself from harm. 

Dead skin cells are created by your skin as a byproduct of epidermal turnover — the process by which your skin creates new skin cells to renew itself.

When too much sebum builds up inside one of your pores, it can mix with leftover skin cells and develop into a whitehead or blackhead.

Inflammatory acne lesions, such as papules and pustules, develop when bacteria multiply inside a blocked pore, causing it to become red, swollen and painful. 

The most severe forms of inflammatory acne develop when acne lesions become larger or form deep within your skin.

A variety of different factors, from your genetics to your habits and behavior, may increase your risk of dealing with acne. We’ve listed some of the most common risk factors for and causes of acne breakouts below.

Menstrual Cycle

As we briefly mentioned above, your hormones play a key role in your risk of experiencing acne breakouts. 

This is because certain hormones, such as testosterone, control your production of sebum, the oil-like substance that can clog your pores and cause acne to develop.

Shortly before and during your period, your hormone levels fluctuate. This may cause your skin to become oilier and more prone to breakouts known as period acne

Period acne is common. In fact, a 2013 study published in the Journal of Clinical and Aesthetic Dermatology found that 65 percent of women reported that their acne symptoms became more severe with their period.

Many women find that hormonal birth control, which regulates hormone levels, helps to prevent this form of acne. 

As well as your period, health issues or diseases that affect your production of androgens may also contribute to acne breakouts. 

For example, acne is a common symptom of polycystic ovary syndrome — a disorder that may cause you to produce abnormally high levels of acne-causing hormones like testosterone.


Although there’s no “acne gene,” research shows that some genetic mutations may affect your risk of developing acne throughout your life.

For example, clinical findings suggest that acne tends to run in families, meaning you may be more likely to develop acne if your parents also experienced acne breakouts.

A study involving more than 1,500 pairs of adult twins, which used genetic modeling based on acne score data, found that more than 80 percent of variance in acne is attributable to genetic factors.

This study also found that 19 percent of the variance in acne was attributable to environmental factors, meaning acne isn’t purely genetic.

Birth Control

For most women, hormonal methods of birth control such as the pill and patch don’t cause acne breakouts. In fact, birth control is widely used as a treatment for certain types of acne.  

Despite this, some forms of birth control can temporarily cause acne when you first start to take them, even though they’re effective at preventing acne over the long term.

For example, acne is listed as a known side effect of the birth control pills Yaz®, Ortho Tri-Cyclen® and Estrostep®, even though all three of these birth control pills have been approved by the FDA as treatments for acne.

This may be linked to the fluctuations these medications can cause in your body’s production of certain hormones, including hormones that contribute to acne breakouts. 

When used over the long term, these forms of birth control have been proven to treat acne and give you clearer skin. 


Smoking isn’t just bad for your heart and lungs. Research also shows that smoking is harmful to your skin and can increase your risk of developing acne breakouts.

In a study that involved more than 1,000 women, researchers found a direct correlation between smoking and acne, with women who smoked showing a higher-than-normal prevalence of adult acne.

A different study published in the International Journal of Research in Dermatology found a link between nicotine dependence and acne severity.

In this study, the researchers concluded that people who smoke were more than twice as likely as non-smokers to develop acne.


Research shows that stress and acne are linked, meaning you may be more at risk of dealing with acne breakouts if you’re stressed due to your career, studies or personal life.

In one study of medical students, researchers found that women with high levels of perceived stress had more severe acne than their less stressed peers.

Another small study involving university students found that the students’ acne became worse during examinations, when they reported the highest stress levels.

Although this doesn’t necessarily mean that stress causes acne directly, it suggests that stress could make your existing acne worse — a phenomenon known as stress acne

You can reduce stress by exercising, eating a balanced diet, avoiding substances like caffeine and nicotine, practicing relaxation techniques and limiting your exposure to stress triggers.

Learn more about the causes and risk factors for acne.

Acne Treatment Options

Whether you get the occasional pimple or severe acne, it’s possible to treat acne using topical and oral medications. 

While some acne medications require a prescription, many are available over-the-counter from your local drugstore. We’ve discussed the treatment options for acne below.

Over-the-Counter and Drugstore Acne Treatments

If you have mild acne, over-the-counter products such as facial cleansers may help to get your breakouts under control and clear your skin. 

One of the most effective ways to control acne is by washing your face regularly using a gentle cleanser. Look for the following science-based ingredients:

  • Benzoyl peroxide. This helps to prevent the growth of bacteria that can cause inflamed acne breakouts.

  • Salicylic acid. This ingredient works by unclogging blocked pores and reducing swelling and redness that can develop with inflamed acne.

  • Alpha-hydroxy acids. These ingredients promote exfoliation and can help to strip away dead skin cells that build up on your skin’s surface.

Our guide to the best face washes for acne goes into more about how these ingredients work to get rid of pimples and prevent acne from coming back. Many of these ingredients can also be found in other over-the-counter products, including acne masks, creams and serums.

Topical Retinoids

Topical retinoids are a class of medications that work by increasing the speed at which your skin produces new cells, helping to reduce dead skin cell buildup and get rid of acne

The most well-known topical retinoid is tretinoin, a prescription medication that’s widely used for acne and anti-aging purposes. Tretinoin and other retinoids are backed up by a huge amount of research and have been referred to as the “mainstay” of therapy for acne.

Tretinoin is one of several active ingredients in our Prescription Acne Cream, which is tailored to treat your specific acne needs. 

Other popular topical retinoids for treating acne include adapalene and retinol, both of which are available in over-the-counter acne creams, serums and other products. 

Antibiotics for Acne

Because acne is aggravated by bacteria, it’s often treated using antibiotics. Both topical and oral antibiotics are used to treat acne, with oral antibiotics usually reserved for severe acne. 

Antibiotics used to treat acne include:

  • Clindamycin. This medication works by reducing swelling and slowing down or stopping the growth of bacteria that can cause inflamed, infected acne.

  • Tetracycline and macrolide antibiotics. These oral medications may be used to treat severe forms of acne, such as nodular or cystic acne. 

Currently, all of these antibiotics require a prescription, meaning you’ll need to talk to a licensed healthcare provider in order to use this type of acne treatment. 

Birth Control for Acne

Several combination birth control pills — pills that contain an estrogen and progestin hormone — are used to treat acne.

As a treatment for acne, birth control pills work by reducing your body’s production of androgen hormones such as testosterone. Since testosterone controls sebum, this may make your skin less oily and prone to acne breakouts. 

Currently, the FDA has approved three birth control pills as acne treatments: Yaz, Estrostep and Ortho Tri-Cyclen. 

All of these pills contain a combination of estrogen and progestin hormones and require a valid prescription to purchase and use. There are currently no progestin-only pills, or “mini-pills,” that are approved to treat acne. 

Our guide to using the birth control pill for acne offers more information on how you can use oral contraceptives to prevent breakouts and improve your skin. 


Microdermabrasion is a cosmetic procedure that involves carefully sanding away the outermost layers of your skin using a minimally invasive instrument, letting new skin grow in its place.

This process helps to get rid of both acne and acne scars, as well as other common skin issues such as fine lines, wrinkles, age spots and hyperpigmentation (dark skin patches).

Microdermabrasion isn’t normally necessary if you only get mild acne. However, if you’re prone to severe acne breakouts, or if you have acne scars that you’d like to lighten and get rid of, this type of procedure can be very effective. 

According to the American Society of Plastic Surgeons, a single session of microdermabrasion costs $136 on average, excluding related expenses. It may take several treatments to see an improvement in your skin’s texture and appearance. 

Chemical Peels for Acne

Chemical peeling is a type of skin resurfacing procedure that involves stripping away the outer layer of your skin using a chemical solution, typically an acid.

Several different chemicals are used for this procedure, including glycolic acid, trichloroacetic acid or phenol (carbolic acid). The solution is applied in a controlled, safe environment by a qualified dermatologist or plastic surgeon.

By stripping away the outermost layer of your skin, chemical peeling stimulates the growth of a new layer of skin and gets rid of acne, scarring, age spots, wrinkles and other imperfections.

Chemical peels for acne can vary in depth and intensity. Most of the time, a light chemical peel, which is designed to remove the outer layer of your skin in a light exfoliation, is powerful enough to treat acne and give your skin a healthier glow. 

According to the American Society of Plastic Surgeons, the average cost of a chemical peel is $644. This figure may vary based on the depth of the peeling procedure you choose. 

Skin Care Routine for Acne

Since acne can vary so much in type and severity, there’s no one-size-fits-all solution that will stop breakouts and provide clear, blemish-free skin for everyone. 

However, by following a few simple guidelines and maintaining a consistent skin care routine for acne, you can get the best results from your acne treatment. Make sure that you:

  • Follow your routine consistently. Whether you’re prescribed medication to treat acne or use over-the-counter products, make sure to follow the usage instructions and stick to your routine.

  • Wait several months for results. Many acne treatments, including medications such as tretinoin, take several months to start working. Keep using your acne medication, even if you don’t notice immediate results.

  • Have realistic expectations. If you have severe acne, it may take some experimenting to find the most effective treatment for you. Be prepared to work with your dermatologist or other healthcare provider to find a routine that meets your skin care needs. 

Uncover the best acne treatment options that are backed by science.

How to Prevent Acne

Even after you’ve treated acne, it’s important to plan ahead to prevent your acne breakouts from coming back. 

You can reduce your risk of dealing with acne by making a few small changes to your habits and skin care routine. 

Wash Your Face

Washing your face on a regular basis helps to get rid of the sebum, dead skin cells, perspiration and bacteria that can contribute to acne breakouts.

The American Academy of Dermatology recommends washing your face twice a day, as well as after sweating. 

For best results, use a non-abrasive cleanser such as our Deep Sea Cleanser. When you wash your face, gently use your fingertips to apply cleanser, then rinse it off using warm water. 

After you finish, carefully pat your skin dry with a clean towel. 

Buy Makeup That’s Designed for Acne-Prone Skin

Many cosmetics contain oils and other ingredients that can clog your pores and make your acne breakouts worse.

When you’re shopping for makeup, look for products that are labeled “non-comedogenic” or “oil free.” These are formulated specifically to have a lower risk of causing acne breakouts for most people.

Use a Moisturizer for Acne-Prone Skin

Moisturizer helps to trap water in your skin, which is particularly important if you use medication such as benzoyl peroxide, salicylic acid or tretinoin, all of which can cause dryness.

When you’re shopping for moisturizers, look for products that use an oil-free, non-comedogenic formula. Our guide to the best moisturizers for acne-prone skin lists ingredients to look for in an effective facial moisturizer, as well as oils and other ingredients that are best avoided. 

Drink More Water

Dehydration can dry out and irritate your skin, causing your sebaceous glands to produce more oil and increasing your risk of dealing with acne breakouts. 

Does drinking water help acne? While the link between water and acne-free skin isn’t as clear as many people think, keeping yourself hydrated offers benefits for your skin and your general health, making it something worth prioritizing.

As for how much you should drink, the classic “eight glasses of eight ounces” advice is a good daily target for most people.

Don’t Touch Your Face

While it might feel tempting to touch your face during an acne breakout, doing so usually isn’t a good idea. 

Your hands are a major vector for transferring bacteria. When you touch your face, it’s easy to spread this bacteria onto your skin and into your pores, which could cause your acne breakouts to become worse. 

It’s especially important not to pop or squeeze your pimples, as this can force debris deeper into your skin and increase your risk of developing more severe forms of acne.

Remember to Use Sunscreen

Although sunscreen doesn’t directly prevent acne, it helps to stop your skin from becoming dried out and burned, which can stimulate sebum production and worsen acne breakouts.

Using sunscreen also protects your skin from UV radiation — a major source of damage to your skin that can worsen things like wrinkles, age spots and discoloration.

The American Academy of Dermatology recommends using an SPF 30+ sunscreen with broad spectrum protection and water resistance.

Our guide to the best sunscreen for acne-prone skin lists key ingredients to look for when you’re shopping for daily sunscreen

Avoid Foods That Cause Acne

While your diet isn’t the biggest factor in acne breakouts, the foods you eat do play a role in the appearance of your skin.

For example, research has found that some foods, such as processed meats and high-glycemic index, high-calorie foods, may worsen inflammation and contribute to acne breakouts.

To keep your skin free of blemishes, try to avoid processed foods and stick to a diet that’s rich in fruits, vegetables, and lean sources of protein such as fish.

Our guide to what foods cause acne lists specific foods to either avoid entirely or limit to ensure your skin looks its best.  

Learn more about how you can prevent acne breakouts.

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Learn More About Acne

Acne is an annoying issue that almost everyone deals with at some point in life, whether it’s in adolescence, adulthood or both.

While acne breakouts can take a major toll on your appearance and self-esteem, the reality is that acne is treatable. 

With the right mix of science-based acne creams, good skin care habits and patience, you can get rid of acne and enjoy clear skin, even if you’re normally prone to severe breakouts of inflammatory acne.

For more information about acne, you can find out how to get rid of acne fast, identify skincare mistakes to avoid and discover the difference between acne and pimples with our guides.

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Hims & Hers has strict sourcing guidelines to ensure our content is accurate and current. We rely on peer-reviewed studies, academic research institutions, and medical associations. We strive to use primary sources and refrain from using tertiary references.

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This article is for informational purposes only and does not constitute medical advice. The information contained herein is not a substitute for and should never be relied upon for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment. Learn more about our editorial standards here.