Licorice root extract works against acne by reducing inflammation and regulating sebum production, while simultaneously addressing post-inflammatory hyperpigmentation through glabridin and liquiritin compounds that inhibit melanin synthesis. If you’ve dealt with acne scars that leave behind dark marks or brown spots on your skin, licorice root offers a dual benefit: it calms the active breakout while also fading the discoloration that follows. This article explores how licorice root extract delivers these benefits, what the science says about its effectiveness, how to use it properly, and when you might need to combine it with other treatments for better results.
Table of Contents
- How Does Licorice Root Extract Reduce Acne Inflammation and Breakouts?
- Why Does Licorice Root Extract Fade Post-Inflammatory Hyperpigmentation?
- What Form of Licorice Root Extract Works Best for Acne and PIH?
- How to Use Licorice Root Extract for Maximum Acne and PIH Benefits
- Does Licorice Root Extract Work for All Types of Acne and Skin Tones?
- Can You Combine Licorice Root with Other Acne Treatments?
- What’s the Long-Term Outlook for Treating Acne and PIH with Licorice Root?
- Conclusion
- Frequently Asked Questions
How Does Licorice Root Extract Reduce Acne Inflammation and Breakouts?
Licorice root contains several bioactive compounds—primarily glabridin, liquiritin, and glycyrrhizin—that suppress inflammatory pathways in the skin. When acne bacteria trigger an immune response, your skin releases cytokines and inflammatory mediators that create the red, swollen, painful appearance of a pimple. Licorice root blocks these inflammatory signals without suppressing your overall immune system, which means it calms the breakout without leaving you vulnerable to infection. Studies show that licorice root can reduce sebum production by up to 30-40% in some users, addressing one of the root causes of acne since excess oil feeds the bacteria that cause breakouts.
The anti-inflammatory effect typically appears within 2-4 weeks of consistent use, though individual timelines vary. Someone with hormonal acne driven by oil overproduction may see faster results than someone with bacterial acne alone. Licorice root also possesses antimicrobial properties that directly suppress *Cutibacterium acnes* (formerly *Propionibacterium acnes*), the primary bacteria responsible for inflammatory acne. However, it’s not as potent as benzoyl peroxide or antibiotics for killing bacteria, so it works better as a supporting ingredient rather than a complete acne solution for severe cases.
Why Does Licorice Root Extract Fade Post-Inflammatory Hyperpigmentation?
Post-inflammatory hyperpigmentation (PIH) occurs when melanin-producing cells (melanocytes) become overactive during or after inflammation, leaving behind dark patches or brown spots once the acne heals. This is especially common in people with darker skin tones, where the melanin response to injury is more pronounced. Licorice root addresses PIH through two main mechanisms: glabridin inhibits the enzyme tyrosinase, which is necessary for melanin production, while liquiritin increases the breakdown of melanin already present in the skin. The result is slower melanin synthesis going forward and gradual fading of existing discoloration.
The depigmenting effect is notably slower than the anti-inflammatory effect—expect 6-12 weeks to see meaningful lightening of PIH marks. However, licorice root has a crucial advantage over some depigmenting agents: it doesn’t sensitize the skin or increase photosensitivity, so you don’t need to avoid sun exposure or become cautious about your skin barrier. That said, you still need sunscreen because UV exposure worsens both acne and PIH by deepening existing pigmentation and triggering new melanin synthesis. If you stop using licorice root and don’t protect your skin from the sun, the fading benefits can partially reverse.
What Form of Licorice Root Extract Works Best for Acne and PIH?
Licorice root extract is available in several forms: concentrated extracts (5-20% glabridin content in serums), powders, tinctures, and as an ingredient blended into moisturizers and masks. Concentrated extracts deliver the highest active compound concentration and work fastest, typically showing noticeable effects within 2-3 weeks. Lower-concentration products (those with licorice as a secondary ingredient) take longer and require consistent use for 8-12 weeks before you see meaningful results.
A realistic example: someone using a serum containing 10% licorice root extract, applied twice daily, might notice reduced redness after 3 weeks and some PIH fading after 6-8 weeks. The same person using a moisturizer with licorice as the fifth ingredient might need 12+ weeks to see comparable fading. This doesn’t mean the lower-concentration product is worthless—it’s gentler on the skin barrier and better tolerated by people with sensitive skin, but the tradeoff is longer wait times. Additionally, how licorice root is extracted matters: water-based extracts contain different compounds than alcohol-based or CO2 extracts, which can affect both potency and skin feel.
How to Use Licorice Root Extract for Maximum Acne and PIH Benefits
For best results, apply licorice root extract serum or concentrated form twice daily to clean, dry skin, ideally before other actives or moisturizers. If you’re using multiple acne treatments (like a retinoid or alpha hydroxy acid), apply licorice root either before or after your other treatment, depending on formulation—water-based serums go on first, oils go on last. Most people benefit from waiting 1-2 minutes between application steps to prevent pilling or reduced efficacy.
A practical routine might look like: cleanser → licorice root serum → lightweight moisturizer → sunscreen (morning) or cleanser → other acne treatment (like niacinamide) → licorice root serum → richer moisturizer (evening). The key limitation here is patience: licorice root is not a quick fix. If you need faster results for severe acne, you may need to combine it with prescription treatments like adapalene or benzoyl peroxide. Licorice root shines as a supporting ingredient that reduces irritation from stronger treatments while also fading PIH once the acne settles.
Does Licorice Root Extract Work for All Types of Acne and Skin Tones?
Licorice root extract is effective across most acne types (hormonal, bacterial, inflammatory) and works well for all skin tones, though the benefits appear most visibly on darker skin where PIH is more pronounced. However, there are exceptions. If your acne is driven primarily by bacterial colonization in clogged pores (like comedonal acne), licorice root alone may not penetrate deeply enough or prevent new clogs from forming.
This is a case where combining licorice root with something like salicylic acid or azelaic acid makes more sense than using licorice root alone. There’s also an important consideration for sensitive skin: while licorice root is generally well-tolerated, some people experience mild stinging, redness, or increased sensitivity when first introducing it, especially if their skin barrier is already compromised. Starting with a lower concentration (5%) and using it every other day for the first 2 weeks, then daily, reduces the risk of irritation. If you have rosacea or extremely reactive skin, licorice root can help, but introduce it slowly and monitor for any worsening of flushing.
Can You Combine Licorice Root with Other Acne Treatments?
Licorice root pairs exceptionally well with retinoids (retinol, adapalene, tretinoin) because it reduces the inflammation and irritation that retinoids often trigger during the adjustment period. Many dermatologists recommend applying licorice root in the morning and a retinoid at night to get anti-acne benefits plus anti-PIH support simultaneously. It also combines safely with niacinamide, which independently reduces sebum and has anti-inflammatory properties—together they’re an effective gentle acne combination.
The combination to approach carefully is licorice root with vitamin C serums, because both are sensitive to pH and light exposure, and layering them can reduce the stability of both ingredients. If you want to use both, apply them on alternate mornings rather than together. Licorice root also works well with azelaic acid, which has overlapping anti-inflammatory and anti-PIH benefits, though using both may be redundant unless you have severe, stubborn discoloration.
What’s the Long-Term Outlook for Treating Acne and PIH with Licorice Root?
The evidence on licorice root for acne continues to expand, with recent research focusing on isolating specific compounds (like glabridin) for even more potent, targeted effects. Current skincare products use whole extract, but future formulations may feature purified glabridin or combinations with other melanin inhibitors for faster PIH fading. What remains consistent is that licorice root works best as a sustained treatment rather than something you use for two weeks then stop—the benefits depend on continuous application.
For long-term use, licorice root is safe for years of consistent application without building tolerance or requiring breaks. However, the skincare landscape is shifting toward combination approaches: licorice root for inflammation and mild depigmentation, combined with stronger actives (like hydroquinone or prescription retinoids) for more stubborn or severe acne scarring. If you’re dealing with both active acne and significant PIH, expect a realistic timeline of 3-4 months to see meaningful improvement with licorice root as your primary support ingredient, longer if you’re starting with severe discoloration.
Conclusion
Licorice root extract offers a dual benefit for acne-prone skin: it reduces active breakouts by suppressing inflammation and regulating sebum, while simultaneously fading post-inflammatory hyperpigmentation through melanin-inhibiting compounds. The tradeoff is patience—results take weeks, not days—but the gentleness on your skin barrier and absence of photosensitivity make it a sustainable long-term option that plays well with other treatments.
Start with a concentrated extract (8-10% licorice root) applied twice daily, give it a minimum of 6-8 weeks to evaluate effectiveness for PIH fading, and consider combining it with retinoids or azelaic acid if you’re dealing with both active acne and stubborn discoloration. If you see no improvement in inflammation after 4 weeks, or if your acne is severe, consult a dermatologist about prescription-strength treatments, which licorice root can complement but may not replace entirely.
Frequently Asked Questions
How long before licorice root extract fades acne scars?
Licorice root fades post-inflammatory hyperpigmentation (brown/dark marks) in 6-12 weeks with consistent use, but does not improve textural scarring (pitting or raised scars). For those concerns, you’d need treatments like microneedling or laser resurfacing.
Can I use licorice root extract if I’m already on prescription acne medication?
Yes. Licorice root is gentle enough to use alongside benzoyl peroxide, retinoids, or antibiotics, and actually reduces irritation from these stronger treatments. Just space applications 1-2 minutes apart.
Does licorice root work for hormonal acne?
Licorice root reduces inflammation from hormonal acne and moderately decreases sebum production, but won’t regulate hormones themselves. For hormone-driven acne, it works best as a supporting ingredient combined with birth control or spironolactone.
Is licorice root extract safe for pregnant or breastfeeding skin?
Topical licorice root in skincare products is considered safe during pregnancy and breastfeeding since absorption through the skin is minimal. However, consult your OB-GYN if you’re using high-concentration extracts or have concerns.
Why isn’t my PIH fading if I’ve used licorice root for 4 weeks?
PIH fading is slow (6-12 weeks minimum). If you’re seeing no improvement after 12 weeks, your discoloration may be severe enough to benefit from professional treatments like laser therapy or chemical peels combined with licorice root maintenance.
