That pimple may be gone, but the mark it leaves behind can stay for much longer. The important thing is to identify what you are actually dealing with before choosing a serum.
If the mark is flat and brown or darker than your surrounding skin, it may be post-inflammatory hyperpigmentation (PIH), rather than a true acne scar. If it is flat and red or pink, it may be post-inflammatory erythema (PIE). If the skin is visibly indented or raised, you may be dealing with a true acne scar, which involves a structural change in the skin.
Understanding this difference can help you choose skincare that matches your concern. A pigmentation-focused serum can help improve the appearance of flat dark marks, but it cannot fill an indented scar or flatten a raised scar.
For more information, read our guide on how to remove dark spots caused by pimples.
Deconstruct — Clearing Serum
Acne Mark or Acne Scar? Identify What You're Treating First
People often use the terms acne marks and acne scars interchangeably, but they are not the same concern.
According to the American Academy of Dermatology, a flat spot of colour that appears after acne clears is usually not an acne scar. It may be post-inflammatory hyperpigmentation (PIH). True acne scars involve changes in the structure or texture of the skin, such as depressions or raised areas. American Academy of Dermatology: Acne scars
Flat Brown or Dark Marks After Acne: PIH
Post-inflammatory hyperpigmentation (PIH) is a flat area of darker pigmentation that can appear after inflammation from acne or another skin injury.
Depending on your skin tone, PIH may appear brown, dark brown, greyish or other darker shades. These marks are flat to the touch and do not change the physical texture of the skin.
- Flat and smooth
- Brown, dark or greyish in appearance
- Often appears after an acne breakout heals
- Related to increased pigmentation following inflammation
- Can gradually become less noticeable over time
Because PIH is a pigmentation concern rather than a structural scar, a skincare routine focused on pigmentation may help improve its appearance over time.
Red or Pink Marks After Acne: PIE
Post-inflammatory erythema (PIE) refers to persistent red or pink discoloration that can remain after inflammatory acne heals. It is different from PIH because the visible colour is related to vascular changes rather than excess melanin.
This distinction matters because a serum designed primarily for pigmentation may not address persistent redness in the same way it addresses brown or dark marks.
Indented or Pitted Acne Scars
If the skin looks depressed, pitted or uneven even when there is no active acne, you may have an atrophic acne scar.
These scars involve a structural change in the skin. Depending on the type and severity, professional treatments may include procedures such as microneedling, chemical peels, laser treatment or other dermatologist-directed approaches. American Academy of Dermatology: Acne scar treatment
Raised Acne Scars
Raised scars occur when excess scar tissue develops above the surrounding skin. Hypertrophic scars and keloids are examples of raised scars and require a different approach from flat pigmentation.
A topical pigmentation serum should not be considered a replacement for professional evaluation or treatment of a raised scar.
Quick Guide: Which Serum Should You Use?
| What You See | What It May Be | What It Means | Can a Serum Help? |
|---|---|---|---|
| Flat brown or dark mark | PIH | Pigmentation-related discoloration | Yes. Pigmentation-focused skincare may help improve its appearance. |
| Flat red or pink mark | PIE | Post-inflammatory redness | Not necessarily. A pigmentation serum may not directly target the redness. |
| Indented or pitted area | Atrophic acne scar | Structural change in the skin | A serum cannot fill the indentation. Professional treatment may be needed. |
| Raised area | Raised acne scar | Excess scar tissue | A serum is not a substitute for professional scar treatment. |
The key takeaway: If your concern is a flat dark mark, look for a serum formulated for pigmentation. If the concern is a change in skin texture, a serum alone is unlikely to correct the underlying scar.
Can a Serum Remove Old Acne Scars?
A topical serum cannot remove an indented or raised acne scar. True acne scars involve changes in the structure of the skin and may require professional assessment and treatment.
However, if what you call an "old acne scar" is actually a flat dark mark left behind after acne, a pigmentation-focused serum may help improve its appearance over time.
The American Academy of Dermatology notes that PIH is a flat discoloration rather than a true acne scar and that treatment can help these spots fade more quickly. American Academy of Dermatology: Acne scar signs and symptoms
This is why identifying the type of mark should come before choosing a serum.
What Serum Should You Use for Fresh and Old Acne Marks?
If your acne mark is flat and brown or dark, consider a pigmentation-focused serum containing ingredients that can help improve the appearance of uneven pigmentation.
Niacinamide and alpha arbutin are two ingredients commonly used in pigmentation-focused skincare. Niacinamide can help reduce the transfer of pigment-containing melanosomes to surrounding skin cells, while alpha arbutin inhibits tyrosinase, an enzyme involved in melanin production.
For a deeper explanation, see our guide on whether niacinamide can help fade dark spots.
For Fresh Flat Acne Marks
A fresh flat dark mark may be addressed with a consistent pigmentation-focused routine. The goal is not to aggressively exfoliate or use multiple brightening ingredients at once.
A simple routine containing a suitable pigmentation serum, moisturiser and daily sunscreen can be easier to follow consistently.
For Older Flat Acne Marks
Older marks can be more stubborn and may take longer to become less noticeable. However, the age of a mark alone does not determine how quickly it will fade.
Factors such as the depth of pigmentation, ongoing acne, skin tone, sun exposure, irritation and consistency with your skincare routine can all influence the process.
For a more detailed explanation of pigmentation timelines, read how long it takes to fade pigmentation.
How Niacinamide and Alpha Arbutin Help With Dark Spots
Niacinamide
Niacinamide, also known as vitamin B3, is commonly used in skincare for multiple concerns, including uneven skin tone and pigmentation.
One of its roles in pigmentation-focused skincare is helping reduce the transfer of melanin-containing pigment from melanocytes to surrounding skin cells. This can help improve the appearance of uneven pigmentation over time.
Niacinamide can also support the skin barrier, making it a useful ingredient for routines where maintaining skin comfort is important.
Alpha Arbutin
Alpha arbutin is a brightening ingredient that inhibits tyrosinase, an enzyme involved in melanin production.
By targeting a different part of the pigmentation process, alpha arbutin can complement ingredients such as niacinamide in a dark-spot-focused routine.
Why Combine Niacinamide and Alpha Arbutin?
Niacinamide and alpha arbutin work through different mechanisms, which is why they are commonly combined in pigmentation-focused formulations.
Niacinamide: Helps reduce pigment transfer and supports the skin barrier.
Alpha arbutin: Inhibits tyrosinase and targets melanin production.
However, using more active ingredients does not automatically mean faster results. A consistent routine that your skin tolerates is usually more useful than repeatedly changing products.
Deconstruct Clearing Serum for Acne Marks and Dark Spots
Deconstruct Dark Spot Clearing Serum is formulated for concerns such as dark spots, post-acne marks and uneven-looking skin tone.
The current formula contains 5% Niacinamide and 2% Liposomal Alpha Arbutin. The product is also described as clinically tested and uses liposomal technology for alpha arbutin delivery. View the Deconstruct Clearing Serum
What Is Deconstruct Clearing Serum Suitable For?
- Flat post-acne dark marks
- Dark spots
- Post-acne pigmentation
- Uneven-looking skin tone
- Dull-looking skin
What Is It Not Designed To Treat?
- Deep pitted acne scars
- Indented scars
- Raised acne scars
- Structural changes in the skin
Being clear about this distinction is important: the Clearing Serum is a pigmentation-focused serum, not a treatment for structural acne scars.
How to Use a Serum for Fresh and Old Acne Marks
Morning Routine
- Cleanser
- Deconstruct Dark Spot Clearing Serum
- Moisturiser
- Sunscreen
Evening Routine
- Cleanser
- Deconstruct Dark Spot Clearing Serum
- Moisturiser
Deconstruct recommends applying 2–3 drops of the Clearing Serum to cleansed skin and gently massaging until absorbed. The serum can be used AM and PM according to the product directions and your skin's tolerance. See the full product directions
If your skin becomes irritated, reduce the frequency rather than adding more brightening or exfoliating products. Irritation can make pigmentation concerns more difficult to manage.
Why Sunscreen Matters When Treating Acne Marks
If you are trying to fade post-acne pigmentation, sunscreen should be a consistent part of the routine.
UV exposure can contribute to worsening pigmentation, while protecting the skin from the sun can help prevent additional discoloration and protect the progress made with your skincare routine.
The American Academy of Dermatology recommends daily sunscreen as part of care following acne-scar treatment and recommends broad-spectrum, water-resistant sunscreen with SPF 30 or higher in that context. American Academy of Dermatology: Acne scar aftercare
The Simple Routine Principle
Target the mark + protect the skin.
A pigmentation serum is designed to address existing pigmentation concerns, while sunscreen helps protect your skin from UV exposure that can worsen discoloration.
If you want to build a complete pigmentation routine, see our guide to an anti-pigmentation skincare routine.
How Long Do Old Acne Marks Take to Fade?
There is no single timeline that applies to every acne mark.
Flat post-acne pigmentation can become less noticeable over weeks to months, but stubborn pigmentation may take considerably longer. The timeline depends on factors such as:
- How long the mark has been present
- Depth of pigmentation
- Skin tone
- Continued acne and inflammation
- Sun exposure
- Skin irritation
- Consistency of your routine
- Ingredients and formulation used
Fresh does not always mean easy, and old does not automatically mean permanent.
For more information, read How Long Does It Take to Fade Pigmentation?
Common Mistakes When Treating Acne Marks
1. Picking or Popping Acne
Picking, squeezing or scratching acne can increase inflammation and may increase the risk of discoloration and scarring. The American Academy of Dermatology recommends treating acne rather than picking at breakouts. American Academy of Dermatology: Causes of acne scars
2. Treating a Textural Scar Like a Dark Spot
A brightening serum can be useful for pigmentation, but it cannot simply fill an indentation or remove a raised scar.
3. Skipping Sunscreen
UV exposure can make pigmentation more difficult to manage. Daily sunscreen should therefore remain part of your routine when treating dark spots.
4. Using Too Many Brightening Actives
Adding several strong actives at once can increase the risk of irritation. Keep your routine simple and introduce products gradually.
5. Expecting Overnight Results
Dark spots do not usually disappear overnight. Give your routine enough time to work and evaluate progress consistently rather than changing products every few days.
6. Changing Serums Too Frequently
Switching between products too often makes it difficult to know what is working and may unnecessarily irritate your skin.
7. Ignoring New Breakouts
If new acne continues to appear, new marks can continue to develop. Managing active acne is therefore an important part of preventing additional post-acne pigmentation and scarring.
For guidance on managing acne alongside pigmentation, read How to Treat Acne and Pigmentation Together.
When Should You See a Dermatologist for Acne Scars?
Consider seeing a dermatologist if you are unsure whether you have pigmentation or a true acne scar, particularly if the skin is indented, raised, painful or persistent.
Professional evaluation can help identify the type of scar and determine which treatment is appropriate. Different acne scars can require different treatment approaches, and dermatologists may use procedures such as microneedling, chemical peels, laser treatments or other treatments depending on the type and severity of scarring. American Academy of Dermatology: Acne scar consultation and treatment
You should also consider professional advice if active acne continues to cause new marks or scars despite your current routine.
Frequently Asked Questions
Can a serum remove old acne scars?
A serum cannot remove an indented or raised acne scar because these involve structural changes in the skin. However, a pigmentation-focused serum may help improve the appearance of flat dark marks left behind after acne.
What serum is best for acne marks?
For flat dark acne marks, a serum containing pigmentation-focused ingredients such as niacinamide and alpha arbutin may be a useful option. The Deconstruct Clearing Serum contains 5% niacinamide and 2% liposomal alpha arbutin and is formulated for dark spots, post-acne marks and uneven skin tone.
Is niacinamide good for acne marks?
Niacinamide can help improve the appearance of uneven pigmentation and dark spots. It can also support the skin barrier, making it a useful ingredient in a consistent routine for post-acne marks.
Is alpha arbutin good for acne marks?
Alpha arbutin is a pigmentation-focused ingredient that inhibits tyrosinase, an enzyme involved in melanin production. It may help improve the appearance of dark spots and post-acne pigmentation over time.
How do I know if I have acne scars or dark spots?
If the area is flat and only differs in colour from the surrounding skin, it may be a post-acne mark such as PIH. If the skin is indented, pitted or raised, it is more likely to be a true acne scar. A dermatologist can provide an accurate assessment if you are unsure.
Can a serum treat pitted acne scars?
A topical serum cannot fill or remove a pitted acne scar. Pitted scars involve structural changes in the skin and may require professional treatments such as microneedling, chemical peels, laser treatment or other dermatologist-directed procedures.
How long do old acne marks take to fade?
There is no fixed timeline. Flat post-acne pigmentation can take weeks to months to become less noticeable, while deeper or stubborn pigmentation may take longer. Consistent skincare and sun protection can support the process.
Should I use sunscreen while treating acne marks?
Yes. Sunscreen should be part of a pigmentation-focused routine because UV exposure can worsen discoloration. Use a broad-spectrum sunscreen during the day and reapply according to the product directions and your level of sun exposure.
Final Thoughts
Before choosing a serum for an "acne scar," first identify what you are actually seeing.
Flat brown or dark marks are more likely to be pigmentation such as PIH, while red or pink marks may be PIE. Indented or raised areas are more consistent with true acne scars.
If your concern is a flat post-acne dark mark, a consistent pigmentation-focused routine can help improve its appearance over time. Deconstruct's Dark Spot Clearing Serum, formulated with 5% Niacinamide and 2% Liposomal Alpha Arbutin, is designed specifically for dark spots, post-acne marks and uneven-looking skin tone.
True indented or raised acne scars are different. They involve structural changes in the skin and may require professional assessment and treatment rather than a pigmentation serum alone.
Most importantly, don't forget sunscreen. Target the mark, protect the skin, manage active acne and give your routine enough time to work.
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