Acne Explained: Causes and Treatments

Acne is not caused by dirty skin, and treating it effectively usually requires more than simply washing your face or drying out pimples. Understanding what is happening inside the pore can help you choose treatments that actually target the causes of acne, reduce ongoing breakouts, and lower the risk of persistent marks and scarring.

Acne is one of the most common skin conditions, yet it remains surrounded by misinformation.

Patients are often told they need to wash their face more, eliminate certain foods, dry out their skin, or find the one “miracle” product that will finally solve the problem. In reality, acne is a complex inflammatory skin condition involving the hair follicle and its associated oil gland.

That distinction matters because treating acne properly starts with understanding why the breakout is happening.

In this guide, we’ll cover:

• How acne actually develops
• The difference between blackheads, whiteheads, pimples, nodules, and cysts
• Which ingredients can help different types of acne
• Common skincare habits that can make acne worse
• The difference between acne marks and true acne scars
• When it may be time to see a dermatologist

Once you understand the mechanism behind acne, the treatment options start to make much more sense.

How Does Acne Actually Develop?

Acne begins in a structure called the pilosebaceous unit, which includes a hair follicle and the sebaceous gland that produces oil, or sebum.

Several processes interact to create an acne lesion. These include increased sebum production, abnormal accumulation of dead skin cells within the follicle, proliferation of Cutibacterium acnes, and inflammation.

1. Increased Oil Production

Sebaceous glands naturally produce oil to help protect the skin.

Hormones, particularly androgens, can increase the activity of these glands. This is one reason acne commonly appears during puberty, but hormonal influences can continue well into adulthood.

Having oily skin does not automatically mean you will develop acne. However, increased oil production helps create an environment where pores are more likely to become congested.

The goal of acne treatment is therefore not to eliminate every trace of oil from the skin. Aggressively drying or stripping the skin can create irritation without addressing the underlying cause of acne.

2. The Pore Becomes Blocked

Skin cells are constantly being produced and shed.

In acne-prone skin, cells lining the follicle can accumulate rather than shedding normally. When these cells mix with sebum, they can create a plug inside the pore.

If the follicle remains closed at the surface, it appears as a whitehead, also called a closed comedone.

If the follicle is open, it appears as a blackhead, or open comedone.

Despite the name, the dark colour of a blackhead is not dirt. Blackheads contain oil and cellular debris within an open follicle, and their dark appearance results from changes that occur when this material is exposed at the skin's surface.

When acne consists primarily of blackheads and whiteheads, we call it comedonal acne.

3. Bacteria Proliferate Inside the Follicle

Cutibacterium acnes, often abbreviated C. acnes, naturally lives on human skin.

Its presence does not mean your skin is dirty.

When a follicle becomes blocked with oil and dead skin cells, conditions inside the pore can favour increased bacterial activity. This contributes to the inflammatory response that produces many of the red, swollen lesions associated with acne.

This is why simply washing the surface of the skin cannot “clean away” acne.

4. Inflammation Develops

Inflammation is what transforms a clogged pore into the red, swollen lesions most people associate with a breakout.

Depending on the depth and severity of the inflammation, acne can appear as:

• Papules, or small red bumps
• Pustules
• Deeper nodules
• Cysts or cyst-like inflammatory lesions

The deeper and more inflammatory the acne becomes, the greater the potential for permanent scarring.

This is one reason persistent, painful, or deep acne should be treated early rather than waiting for it to disappear on its own.

Different Types of Acne Need Different Treatments

Not every breakout should be treated the same way.

Identifying the dominant type of acne helps determine which ingredients or medications are most likely to be useful.

Comedonal Acne

Comedonal acne consists primarily of:

• Blackheads
• Whiteheads
• Small skin-coloured bumps
• Uneven or congested texture

Because pore blockage is the dominant problem, treatment usually focuses on keeping follicles clear and normalizing skin-cell turnover.

Topical retinoids and salicylic acid are among the treatments recommended in current acne guidelines.

Inflammatory Acne

Inflammatory acne produces:

• Red pimples
• Papules
• Pustules
• Tender lesions

Here, treatment needs to address both clogged follicles and inflammation.

Retinoids are frequently combined with treatments such as benzoyl peroxide. Current American Academy of Dermatology guidelines strongly recommend both topical retinoids and benzoyl peroxide as acne treatments.

Nodular or Severe Acne

Large, deep, painful lesions have a significantly higher potential to leave scars.

These cases often require prescription treatment rather than relying exclusively on skincare products.

Depending on the patient and the type of acne, dermatologists may consider topical medications, oral antibiotics, hormonal therapies, or isotretinoin. Current acne guidelines include all of these among evidence-supported treatment options.

Early assessment is particularly important when acne is deep, painful, rapidly worsening, or already producing scars.

How to Start Treating Acne at Home

For mild acne, a simple routine using evidence-based ingredients is often a reasonable place to begin.

The biggest mistake is frequently trying to do too much at once.

Start With the Basics

Before creating a complicated acne routine, establish three fundamentals:

• A gentle cleanser
• A non-comedogenic moisturizer
• Daily sunscreen

Acne-prone skin still needs a healthy skin barrier.

Scrubbing aggressively, washing repeatedly throughout the day, or constantly switching products can increase irritation. Dermatologists generally recommend gentle cleansing up to twice daily and after significant sweating.

Once your skin tolerates the basic routine, targeted active ingredients can be introduced gradually.

Retinoids for Clogged Pores and Acne Prevention

Retinoids are among the most useful medications in acne treatment because they help prevent pores from becoming clogged and also have anti-inflammatory effects.

Depending on the product, this category includes cosmetic retinol and retinal as well as medications such as adapalene and tretinoin.

If you are new to a retinoid, introducing it gradually can help reduce irritation.

A simple approach may include:

• Starting a few evenings per week
• Applying a thin layer rather than using more product
• Increasing frequency as tolerated
• Following with moisturizer if dryness develops

More product does not necessarily mean faster results.

Important: Retinoids should generally be avoided during pregnancy. If you are pregnant, trying to become pregnant, or breastfeeding, discuss acne treatment with your physician rather than building a treatment routine on your own.

Salicylic Acid for Congested Skin

Salicylic acid is another evidence-supported acne ingredient and can be particularly useful when blackheads and whiteheads are prominent.

It can be found in cleansers, leave-on treatments, and other acne products.

If you are already using a retinoid, there is usually no reason to introduce multiple exfoliating acids simultaneously. Start slowly and pay attention to irritation.

Redness, excessive peeling, burning, and persistent sensitivity are signs that your routine may be too aggressive.

Benzoyl Peroxide for Inflammatory Acne

Benzoyl peroxide is particularly useful when acne includes red, inflammatory pimples.

It helps reduce acne-associated bacteria and inflammation and remains one of the treatments strongly recommended in acne management guidelines.

It is available in both leave-on products and cleansers.

A wash can be a convenient option for people who want to limit how many leave-on active ingredients they are layering on the skin.

Again, stronger is not automatically better. Irritation can make an already complicated acne routine harder to tolerate.

Azelaic Acid: A Useful Multi-Tasking Ingredient

Azelaic acid is an especially versatile ingredient because it can address more than one component of acne.

It has:

• Anti-inflammatory activity
• Comedolytic properties
• Activity against acne-associated bacteria
• Benefits for post-inflammatory pigmentation

The American Academy of Dermatology includes azelaic acid among recommended topical acne therapies and notes that it can also help treat dark marks that remain after acne clears.

It can be particularly useful for patients who are dealing with both active breakouts and pigmentation.

Azelaic acid is also considered a treatment option during pregnancy, although it is still sensible to discuss skincare medications with your physician while pregnant.

One of the Best Things You Can Do: Stop Picking

Trying to squeeze a pimple feels productive because you can see something happening immediately.

Unfortunately, it can make the situation worse.

Picking, squeezing, or scratching acne increases inflammation and can raise the risk of discoloration, infection, and permanent scarring.

Professional acne extraction is different. Dermatologists use sterile instruments and appropriate techniques to extract certain lesions safely when clinically appropriate.

Your bathroom mirror is not a dermatology procedure room.

Common Acne Myths That Can Make Things Worse

Myth #1: Acne Means Your Skin Is Dirty

Acne develops inside the follicle through a combination of oil production, pore blockage, bacterial activity, and inflammation.

Washing your face harder will not remove that process.

Overwashing and scrubbing can instead irritate acne-prone skin.

Myth #2: More Active Ingredients Mean Faster Results

Using a retinoid, exfoliating acid, benzoyl peroxide, vitamin C, scrub, toner, and spot treatment simultaneously does not necessarily make acne disappear faster.

It may simply make your skin irritated.

Introduce treatments gradually and give them time to work.

Myth #3: Popping a Pimple Helps It Heal

Squeezing can push inflammatory material deeper into the skin and increase inflammation.

This can make acne more noticeable and increase the chance of discoloration and scarring.

Myth #4: DIY Treatments Are Safer Because They're “Natural”

Lemon juice, rubbing alcohol, toothpaste, harsh scrubs, and similar home remedies are not substitutes for proven acne treatments.

Irritating the skin barrier does not treat the underlying biology of acne.

Myth #5: If It Burns, It Must Be Working

Burning is not a measure of effectiveness.

Acne treatments can cause some dryness or irritation, particularly when first introduced, but persistent burning or significant inflammation is a reason to reassess the routine.

Acne Marks Are Not Always Acne Scars

One of the most important distinctions in acne treatment is the difference between changes in colour and changes in skin structure.

Patients often call both of these “scars,” but they are not the same thing.

Post-Inflammatory Erythema (PIE)

PIE describes flat red or pink marks that remain after an inflammatory acne lesion resolves.

These marks are related to vascular changes following inflammation and are more noticeable in lighter skin tones.

Post-Inflammatory Hyperpigmentation (PIH)

PIH appears as flat brown, grey-brown, or darker areas after inflammation.

It occurs when inflammation triggers excess pigment deposition and tends to be more prominent and persistent in darker skin tones.

Both PIE and PIH can take months to improve, but unlike true scars, they do not represent permanent changes in the contour of the skin.

Treatments may include:

• Daily sunscreen
• Azelaic acid
• Retinoids
• Other pigment-targeting topical treatments

For persistent redness or pigmentation, carefully selected laser and energy-based treatments may also be considered. The appropriate device depends heavily on the type of mark and the patient's skin tone.

What Are True Acne Scars?

True acne scars involve a structural change in the skin.

They generally fall into two broad categories.

Atrophic or Depressed Acne Scars

These develop when insufficient collagen is produced during healing.

Common types include:

• Ice pick scars: narrow and deep
• Boxcar scars: wider depressions with defined edges
• Rolling scars: broader depressions that create an uneven or wavy surface

Different scar shapes respond differently to treatment, which is why there is no single “best acne scar treatment.”

Depending on the scar pattern, a dermatologist may consider procedures such as:

• Chemical reconstruction techniques
• Minor scar surgery
• Subcision
• Microneedling
• Radiofrequency microneedling
• Laser resurfacing
• Chemical peels
• Dermal fillers

Often, the best result comes from combining treatments rather than relying on one procedure.

Hypertrophic and Keloid Scars

Raised acne scars develop when the skin produces excess collagen while healing.

Treatment is very different from treatment for depressed scars and may involve corticosteroid injections, laser therapy, medication injected into the scar, cryotherapy, or surgery in selected cases.

This is another reason accurate scar diagnosis matters.

Can Skincare Products Remove Acne Scars?

This depends on what you mean by “scar.”

Topical ingredients can improve pigmentation, help control active acne, and sometimes make very mild textural irregularities less noticeable.

But a cream cannot reliably rebuild a deep ice pick scar, release a tethered rolling scar, or flatten a substantial keloid.

Established structural scars usually require procedures selected according to the individual scar type.

And before treating scars, the active acne should generally be brought under control so new scars are not continuing to form.

When Should You See a Dermatologist for Acne?

Consider professional assessment if:

• Your acne is painful or deep
• You are developing nodules or cysts
• Breakouts are leaving scars
• Pigmentation is becoming persistent
• Acne is affecting your confidence or quality of life
• Over-the-counter treatments have not produced adequate improvement
• You are unsure whether what you have is actually acne

Early treatment is particularly valuable when scarring has started because preventing a scar is usually easier than treating one later.

The Most Important Ingredient Is Consistency

There is no reliable seven-day acne transformation.

Even an excellent treatment plan needs time.

Acne therapy typically involves a combination of barrier-friendly skincare, targeted active ingredients, and, when appropriate, prescription medication or in-office treatment.

Changing your routine every week makes it difficult to know what is helping and frequently introduces unnecessary irritation. The AAD notes that acne treatments often require several weeks to months before meaningful improvement becomes apparent.

The goal is not to attack your skin.

It is to understand what is driving the acne, treat those mechanisms appropriately, protect the skin barrier, and stay consistent long enough for the treatment to work.

Acne is treatable. The key is choosing the right treatment for the type of acne you actually have.