Why You Are Breaking Out in Your 30s and 40s (And What to Do About It Naturally)

Why You Are Breaking Out in Your 30s and 40s (And What to Do About It Naturally)

Why You Are Breaking Out in Your 30s and 40s (And What to Do About It Naturally)

You thought you left acne behind in high school. You did the work, figured out your skin, and found a routine that worked. And now, somewhere in your 30s or 40s, you are standing at the bathroom mirror looking at your jawline and wondering what on earth is happening.

You are not alone. And you are not imagining it.

Breaking out as an adult woman, especially for the first time or after years of relatively clear skin, is far more common than most people realize. Less commonly understood are why it happens and what your skin actually needs during this phase of life. Because the breakouts you are dealing with now are not the same as the ones you had at sixteen. They have different drivers and patterns, and they respond very differently to the products and approaches that worked for teenage skin.

This post breaks down exactly what is happening inside your body during perimenopause, why it shows up on your face, and how to care for your skin in a way that actually addresses the root rather than chasing symptoms with products designed for a completely different kind of acne.

You Are Not Imagining It: Adult Acne Is Extremely Common in Women

Acne is widely misunderstood as a teenage condition. The reality is that it is one of the most common skin concerns in adult women, and its prevalence in the perimenopausal years is well documented in clinical research.

A comprehensive 2024 review published in the International Journal of Women's Health, examining the epidemiology, treatment approaches, and menopausal influence on adult female acne, found that roughly 26 percent of women in their 40s experience acne, with many cases appearing for the first time during the perimenopausal transition [1]. That means more than one in four women in this age group are dealing with breakouts, often without understanding why, and often using products that were never designed for their specific hormonal situation.

What makes this particularly frustrating is that perimenopausal acne does not always look the way people expect acne to look. It tends to be deeper, more cystic, more painful, and more stubborn than the surface-level breakouts of adolescence. It often appears alongside dry patches and skin sensitivity, creating a confusing combination of oiliness and dryness that can make it difficult to know what kind of skincare your skin actually needs. For a closer look at how to identify different types of skin conditions and recognize their patterns, this guide is a helpful companion: Guide to Spotting and Treating Common Skin Troubles.

What Is Perimenopause, and When Does It Actually Begin?

Perimenopause is the transitional phase that precedes menopause, the period during which the ovaries gradually begin producing less estrogen and ovulatory function becomes irregular. Menopause itself is defined as twelve consecutive months without a menstrual period. Perimenopause is everything leading up to that point.

What surprises many women is how early this transition can begin. Research from the Swiss Perimenopause Study, a longitudinal study following 127 perimenopausal women aged 40 to 56 over 13 months, confirmed that measurable changes in estradiol, progesterone, and cortisol levels occur throughout the perimenopausal window, with significant individual variation in both the timing and pattern of hormonal change [2]. For many women, these hormonal shifts begin in the mid-to-late 30s, well before any changes in the menstrual cycle become obvious.

This matters for skin because the hormonal changes that drive perimenopausal acne can be underway long before a woman identifies herself as perimenopausal. Breakouts that appear to come from nowhere in the mid-30s, or that gradually worsen through the 40s, are often a direct reflection of this slow, years-long hormonal shift.

The Hormonal Shift Behind Perimenopausal Acne

To understand why perimenopausal acne happens, it helps to understand what estrogen normally does for the skin, and what happens when it starts to decline.

Estrogen: The Skin's Protective Hormone

Estrogen plays a significant and underappreciated role in skin health. It supports collagen production, maintains skin hydration, promotes healthy cell turnover, and, crucially, keeps androgen activity in check. When estrogen levels are robust and stable, the sebaceous glands receive a regulatory signal that keeps oil production balanced. Skin stays hydrated, resilient, and relatively clear.

A 2025 systematic review published in Health Science Reports, examining the hormonal etiology of adult female acne, confirmed that androgens play a particularly central role in adult acne by stimulating sebaceous gland growth and increasing sebum secretion. Critically, the review found that even normal circulating androgen levels can drive acne when the balancing effect of estrogen is reduced [3]. In other words, it is not that testosterone suddenly increases. It is when estrogen falls away, and testosterone's effect on the skin becomes disproportionately powerful.

Relative Androgen Dominance: The Real Driver

This is the concept that explains so much of what happens to skin during perimenopause, and yet most women have never heard of it.

During the perimenopausal transition, estrogen and progesterone decline significantly and relatively quickly. Androgens, including testosterone and DHEA-S, produced by the adrenal glands, decline more slowly. This creates a hormonal imbalance that clinicians refer to as relative androgen dominance: a state in which the ratio of androgens to estrogen shifts dramatically, leaving the sebaceous glands disproportionately sensitive to androgenic stimulation [1].

The result is increased sebum production, follicular congestion, and the kind of deep, inflammatory breakouts that characterize hormonal acne. A 2024 review published in the Journal of Dermatological Treatment confirmed that androgen-driven excess sebum production is considered a necessary early step in acne development, making androgen activity one of the most important therapeutic targets in acne management [4]. What makes perimenopausal acne distinct is that this androgen dominance occurs not because androgen levels are unusually high, but because estrogen is no longer present in sufficient quantities to counterbalance them.

Progesterone Decline and Fluctuation

Progesterone adds another layer of complexity to the picture. During perimenopause, progesterone levels fluctuate significantly before ultimately declining. These fluctuations destabilize oil production in their own right. A sharp drop in progesterone allows androgens to become relatively more dominant, contributing to the cyclical nature of perimenopausal breakouts. Many women notice that their skin worsens in the second half of the menstrual cycle, when progesterone rises and then drops, and this pattern can become more pronounced as perimenopause progresses [3].

Cortisol: The Stress Hormone That Makes Everything Worse

The Swiss Perimenopause Study found something particularly important for understanding the full picture of perimenopausal skin: cortisol levels increase measurably throughout the perimenopausal transition [2]. This is significant because cortisol directly stimulates sebaceous gland activity and increases sebum production, independent of androgen activity. It also disrupts the skin barrier, impairs wound healing, and slows the skin's recovery from breakouts.

This means that the hormonal changes of perimenopause and the stress response are not separate problems for the skin. They are compounding ones. A woman navigating the physical and emotional demands of midlife, often while managing career, family, and the symptoms of perimenopause itself, is frequently experiencing elevated cortisol at exactly the time her skin has become most sensitive to its effects. For a deep dive into how cortisol affects the skin, the cortisol and skin health post on this blog covers that connection in full.

How Perimenopausal Acne Differs from Teenage Acne

Understanding how perimenopausal acne is distinct from adolescent acne matters because the approaches that work for one are often counterproductive for the other.

Teenage acne is driven by an overall surge of sex hormones across the board. It tends to appear on the forehead, nose, and T-zone. It is typically more superficial, and it often responds well to oil-stripping and antibacterial treatments because the primary issue is excess oil production across the whole face.

Perimenopausal acne is driven by hormonal imbalance rather than hormonal excess. The 2024 International Journal of Women's Health review confirmed that adult female acne typically presents in the lower face, clustering along the jawline, chin, and lower cheeks in what is called the U-zone, and tends to involve deeper, more inflammatory nodules and cysts rather than surface-level pimples [1]. These lesions are often painful, slow to heal, and more prone to leaving post-inflammatory marks and scarring than the breakouts of adolescence.

To further complicate matters, perimenopausal acne frequently coexists with the skin dryness, sensitivity, and barrier thinning that also accompany estrogen decline. This combination of acne and dryness is genuinely confusing, which is why products designed for oily teenage skin so often make adult hormonal acne worse: they strip an already compromised barrier, trigger compensatory oil production, and add topical irritation to skin already inflamed from the inside.

Other Factors That Contribute to Hormonal Acne in Your 30s and 40s

Hormonal shifts are the primary driver, but they are not the only one. Several other factors can worsen or perpetuate hormonal acne during this stage of life, and understanding them helps explain why some women experience breakouts far more severely than others.

Diet plays a meaningful role. A high glycemic diet raises blood sugar and triggers insulin secretion, which in turn elevates insulin-like growth factor 1, or IGF-1. Research confirms that IGF-1 stimulates sebaceous gland growth, increases sebum production, promotes keratinocyte proliferation, and activates androgen synthesis, thereby amplifying the mechanisms already set in motion by perimenopause [3]. Dairy consumption has also been associated with acne through similar hormonal signaling pathways. Reducing refined sugars, high-glycemic carbohydrates, and dairy can meaningfully reduce the frequency and severity of hormonal breakouts. For skin-loving recipe inspiration that supports blood sugar stability and gut health, this post is a great starting point: 4 Easy Recipes Your Skin Will Love.

Gut health is another significant variable. As explored in the gut and skin health post on this blog, gut dysbiosis drives systemic inflammation that reaches the skin, disrupts the skin microbiome, and worsens the conditions that lead to breakouts. The same dietary changes that support a healthier gut also tend to reduce the hormonal acne driven by perimenopausal shifts.

Sleep disruption is common during perimenopause and has a direct impact on the skin. Poor sleep raises cortisol, worsens systemic inflammation, and impairs the overnight repair process that helps the skin recover from breakouts. Many perimenopausal women find that periods of worse sleep correspond directly with worse skin. For practical support with sleep during this phase, this post covers it well: Sleep Better Naturally: Simple Nighttime Tips for Deep, Restful Sleep.

Over-treating the skin is perhaps the most common and most well-intentioned mistake. When breakouts appear, the instinct is often to reach for stronger, more aggressive products. But perimenopausal skin has a compromised barrier. Harsh cleansers, excessive exfoliation, and layers of active ingredients strip and further destabilize an already-vulnerable surface, triggering increased oil production and inflammation. For a clear breakdown of which common skincare ingredients are most likely to worsen sensitive and reactive skin, this post is essential reading before you overhaul your routine: 5 Ingredients to Avoid if You Have Sensitive or Reactive Skin.

Signs Your Acne Is Hormonal

Not all adult acne is hormonal, though most of it in women over 30 has a hormonal component. Here are the patterns that most clearly suggest a hormonal driver.

Breakouts cluster along the jawline, chin, and lower cheeks rather than the forehead or nose. The lesions are deep, cystic, and painful to touch rather than surface-level blackheads or whiteheads. Flares correlate with your menstrual cycle, particularly in the week before your period, or with periods of heightened stress. Your skin feels simultaneously oily in the T-zone and dry or tight everywhere else. Breakouts linger for two to four weeks rather than resolving within a few days. And perhaps most tellingly, the acne appeared or worsened after years of relatively clear skin, often in the mid-30s or later.

Natural Skincare for Hormonal Acne: The Pretty Farm Girl Approach

Hormonal acne requires a different kind of skincare strategy than most conventional acne products offer. The goal is not to strip or suppress. It is to cleanse without disrupting, calm inflammation without weakening the barrier, and target acne-causing bacteria without creating the kind of irritation that compounds an already inflamed situation.

The following approach is built around that principle, using ingredients rooted in research and formulated specifically for the skin hormonal shifts create.

Step One: Cleanse with Oil, Not with Stripping Surfactants

This is where many women with hormonal acne make their first mistake. They reach for foaming cleansers, salicylic acid washes, or anything marketed as deep-cleaning, believing that the goal is to remove as much oil as possible. But perimenopausal skin needs its natural oils to maintain a functioning barrier. Strip them away and the skin produces more oil in compensation, clogging pores all over again, while the barrier becomes increasingly compromised and reactive.

Oil cleansing works on a different principle entirely: like dissolves like. A well-formulated cleansing oil dissolves the excess sebum and congestion inside the pores without disturbing the acid mantle or triggering the compensatory response that stripping cleansers cause. The result is genuinely clean skin that does not feel tight or depleted afterward.

Pretty Farm Girl's Clarifying Cleansing Oil is formulated with organic jojoba and castor oils, both of which are non-comedogenic and particularly well-suited to acne-prone skin. Jojoba is structurally similar to human sebum, which allows it to absorb into the pores and dissolve congestion without adding to it. Cajeput oil brings antimicrobial and anti-inflammatory properties, and rosemary oil adds antioxidant protection to a formula that cleanses gently yet thoroughly. For a deeper look at why oil cleansing is one of the most effective tools available for adult skin, this post explains it beautifully: Why Cleansing Oils Are the Secret to Anti-Aging Skin.

Step Two: Double Cleanse with the Charcoal Bar

After the oil cleanse, a second cleanse with the Clarifying Charcoal Bar removes any remaining impurities while delivering three powerhouse ingredients directly to congested skin.

Activated charcoal draws excess oil and toxins out of congested pores through adsorption, binding to impurities and lifting them away without disrupting the surrounding skin. Neem oil has a long tradition of use for anti-inflammatory and antimicrobial skin care, particularly suited to acne-prone skin types. Tea tree oil is one of the most well-studied natural antimicrobials in dermatology. A systematic review of 46 randomized controlled trials on Melaleuca alternifolia published in Frontiers in Pharmacology found that tea tree oil demonstrated meaningful clinical benefit for skin conditions, including acne, with antimicrobial mechanisms including disruption of bacterial cell membranes and inhibition of microbial proliferation [5]. The soap's tallow base cleanses while preserving barrier integrity, so this second cleanse deepens the clean without undoing the gentleness of the first step.

Step Three: Balance and Calm with the Clarifying Toner

Immediately after cleansing, the skin's pH has been disrupted, and its surface is temporarily vulnerable. This is when the Clarifying Toner matters most.

The Clarifying Toner is formulated with hypochlorous acid, or HOCl, a naturally occurring molecule produced by the body's own white blood cells as part of its antimicrobial defense system. A status report published in the Journal of Clinical and Aesthetic Dermatology reviewed both in vitro and in vivo evidence for HOCl and confirmed that it exhibits broad-spectrum antimicrobial activity, anti-inflammatory properties, and immunomodulatory effects, with clinical studies demonstrating therapeutic benefit for acne vulgaris and other inflammatory skin disorders [6]. Importantly, HOCl does not generate antibiotic resistance, making it a particularly intelligent choice for a skin condition that is often overtreated with conventional antibacterials. Spritz it directly onto clean skin, allow it to absorb, and follow immediately with the serum.

Step Four: Treat with the Clarifying Spot Treatment Serum

This is the targeted treatment step, and the ingredient list in Pretty Farm Girl's Clarifying Serum for Acne Prone Skin is genuinely impressive.

Black cumin seed oil, or Nigella sativa, is the primary ingredient and one of the most well-researched natural anti-inflammatory botanicals available. Its active compound thymoquinone has demonstrated meaningful anti-inflammatory and antimicrobial activity in clinical research. A randomized double-blind clinical trial published in Phytotherapy Research enrolled 60 patients with acne vulgaris and found that a Nigella sativa hydrogel standardized based on thymoquinone produced significant improvements in Investigator Global Assessment scores compared to placebo over sixty days, confirming its efficacy as a topical acne treatment [7].

Broccoli seed oil contains sulforaphane and other antioxidant compounds that protect the skin from oxidative stress, a key driver of post-inflammatory hyperpigmentation, which is especially common with the deep, slow-healing breakouts of hormonal acne.

Cajeput oil and tea tree oil provide complementary antimicrobial support. Cajeput, extracted from the Melaleuca cajuputi plant and a botanical relative of tea tree, is rich in 1,8-cineole, a compound with well-documented broad-spectrum antimicrobial and anti-inflammatory activity. Research published in BMC Complementary and Alternative Medicine confirmed that Melaleuca cajuputi extracts demonstrate excellent antimicrobial activity against multiple bacterial species, with antioxidant and antibacterial properties confirmed across multiple assays [8]. Together, cajeput and tea tree address the bacterial component of hormonal acne while calming the inflammation that makes perimenopausal breakouts so painful and persistent.

Use the Clarifying Spot Treatment Serum as a spot treatment for active breakouts, or apply it across the entire lower face where hormonal acne tends to cluster.

Step Five: Calm with the Blue Balance Serum

For the inflamed, cystic, angry breakouts that define hormonal acne, the Blue Balance Serum adds a layer of targeted anti-inflammatory support that is difficult to replicate with other ingredients.

Blue tansy oil, the key ingredient, contains high concentrations of chamazulene, the naturally occurring compound responsible for the oil's striking deep blue color and its potent anti-inflammatory properties. Research published in Planta Medica established that chamazulene acts as an antioxidant-type inhibitor of leukotriene B4 formation, a primary mediator of skin inflammation, making it particularly effective for the deep, red, painful cystic breakouts that perimenopause drives [9]. Blue tansy also contains sabinene, which has demonstrated inhibition of pro-inflammatory cytokines, and camphor, which soothes skin irritation and supports tissue repair.

The result is a serum that calms redness, reduces swelling around active lesions, and brings a noticeable sense of relief to skin that has been flaring from within. A few drops pressed into the skin after toning, either alone or layered under the Clarifying Spot Treatment Serum, deliver these benefits directly to inflamed tissue.

Step Six: Seal and Repair with Emu Oil

After treating, the final step is to reinforce the skin barrier and lock in moisture without adding any comedogenic weight to skin already managing congestion.

Emu oil is one of the few ingredients that accomplishes this for acne-prone skin without risk of clogging pores. Its fatty acid profile is so similar to that of human skin that it absorbs rapidly and completely, leaving no residue while delivering anti-inflammatory compounds deep into the tissue. A 2024 study published in the Journal of Functional Foods confirmed that emu oil reduces levels of inflammatory mediators including nitric oxide and tumor necrosis factor-alpha, which is particularly relevant for the inflamed, slow-healing lesions of hormonal acne [10]. It also supports skin barrier repair compromised by perimenopausal hormone changes, helping rebuild the resilience that reduces skin reactivity over time.

For more on how emu oil supports skin at the deeper tissue level, this post covers it in full: Can Emu Oil Help Boost Collagen Production? Here's What I've Learned.

The Kits: A Complete Routine in One Place

If you want to take the guesswork out entirely, Pretty Farm Girl has built two complete acne-focused kits that bring all of these steps together.

The Clarifying Kit for Acne Prone Skin includes the Clarifying Cleansing Oil, Charcoal Clarifying Soap Bar, Clarifying Toner, and Clarifying Spot Treatment Serum. It is a streamlined, four-step routine that covers cleansing, balancing, and targeted treatment in one thoughtfully assembled package.

The Acne Skin Kit: Full Routine is the complete six-product system. It includes everything in the Clarifying Kit plus the Blue Balance Serum and Emu Oil, giving your skin everything it needs to address hormonal breakouts from every angle: bacterial, inflammatory, barrier, and repair. Here is exactly what comes in the kit:

Clarifying Cleansing Oil (2 oz), Charcoal Clarifying Soap (5 oz), Clarifying Toner (2 oz), Blue Balance Serum (0.5 oz), Clarifying Spot Treatment Serum (0.5 oz), and Emu Oil (1 oz).

Each product links to its own individual listing for full ingredient information. All six are handmade, free of synthetic fragrance, and formulated specifically for acne-prone skin that needs calming as much as it needs clearing.

Both kits are built on the same principle that runs through every Pretty Farm Girl product: clean, purposeful ingredients your skin actually recognizes, with nothing that would add further inflammation to a system already managing a significant hormonal load.

A Simple Morning and Evening Routine for Hormonal, Perimenopausal Acne

In the morning, cleanse gently with the Clarifying Cleansing Oil, spritz the Clarifying Toner while the skin is still damp, and apply two to three drops of Blue Balance Serum pressed gently into the skin. Finish with emu oil on any active or inflamed areas. Keep the morning routine simple and barrier-supportive.

In the evening, double-cleanse: first the Clarifying Cleansing Oil, then the Charcoal Bar. Tone with the Clarifying Toner immediately after. Spot treat active breakouts with the Clarifying Spot Treatment Serum, applying it across the lower face if breakouts are widespread. Follow with the Blue Balance Serum, then seal with emu oil.

One to two evenings per week, simplify even further: cleanse, tone, and moisturize only, giving the skin a break from actives and allowing the barrier to rest and repair.

For a full step-by-step skincare routine guide built around Pretty Farm Girl's product range, see the Step-by-Step Skincare Routine Guide.

Frequently Asked Questions About Hormonal Acne in Your 30s and 40s

What causes hormonal acne in your 30s and 40s? The primary driver is a hormonal shift called relative androgen dominance, which occurs as estrogen and progesterone decline during perimenopause while androgens decline more slowly. This leaves the sebaceous glands disproportionately sensitive to androgenic stimulation, resulting in increased oil production and inflammatory breakouts [1] [4].

What is relative androgen dominance? It is the hormonal imbalance that occurs when estrogen falls significantly during perimenopause, while androgen levels remain relatively stable. Even without elevated absolute androgen levels, the reduction in estrogen creates a state in which androgens exert a more pronounced effect on the skin, driving excess sebum production and acne [1].

How is perimenopausal acne different from teenage acne? Teenage acne is driven by an overall hormonal surge and typically appears on the forehead and T-zone. Perimenopausal acne is driven by hormonal imbalance and tends to cluster along the jawline, chin, and lower cheeks. It tends to be deeper, more cystic, more painful, and slower to heal than adolescent breakouts, and it often coexists with skin dryness and sensitivity [1].

Does cortisol cause acne? Yes. Cortisol directly stimulates sebaceous gland activity and increases sebum production. Cortisol levels also measurably increase across the perimenopausal transition, making stress management an important and often overlooked component of managing hormonal acne during this phase [2].

Can you have dry skin and acne at the same time? Yes, and this is one of the hallmarks of perimenopausal acne. The same estrogen decline that drives excess oil production in the sebaceous glands also reduces overall skin hydration and barrier function, creating a combination of breakouts in some areas alongside dryness and sensitivity in others [1].

What foods make hormonal acne worse? High glycemic foods and refined sugars elevate IGF-1, which amplifies androgen activity and stimulates sebum production. Dairy has also been associated with acne through hormonal signaling pathways. Reducing these while increasing omega-3-rich foods, zinc, and dietary fiber supports both gut health and hormonal balance [3].

What skincare ingredients are best for hormonal acne in perimenopause? The most effective approach combines oil cleansing to remove congestion without stripping, antimicrobial botanicals like cajeput, tea tree, and Nigella sativa to target Cutibacterium acnes, hypochlorous acid to calm inflammation and reduce bacteria without disrupting the microbiome, blue tansy and chamazulene to reduce inflammatory mediators, and barrier-supportive ingredients like emu oil to repair and protect a compromised skin surface [5] [6] [7] [8] [9].

The Takeaway

Breaking out in your 30s and 40s is not a mystery, and it is not a failure. It is a predictable consequence of one of the most significant hormonal transitions your body will ever go through, and once you understand what is actually driving it, you can stop reaching for products designed for a completely different kind of acne and start building a routine that genuinely works with your skin.

The hormonal shifts of perimenopause are real. The breakouts they cause are real. And the skin that is navigating all of this is not the same skin it was at sixteen. It deserves an approach built for who you are now, not who you were then.

For a deeper understanding of how skin barrier health connects to everything from breakouts to aging to sensitivity, this post is the perfect next read: Why Your Skin Barrier Matters More Than Botox.

References

  1. Rocha, Marco Alexandre Dias da, Marketa Saint Aroman, Valerie Mengeaud, Fabienne Carballido, Gautier Doat, Ana Coutinho, and Edileia Bagatin. "Unveiling the Nuances of Adult Female Acne: A Comprehensive Exploration of Epidemiology, Treatment Modalities, Dermocosmetics, and the Menopausal Influence." International Journal of Women's Health, vol. 16, 2024, pp. 663-678.

  2. Grub, Jessica, Hannah Suss, Jasmine Willi, and Ulrike Ehlert. "Steroid Hormone Secretion Over the Course of the Perimenopause: Findings From the Swiss Perimenopause Study." Frontiers in Global Women's Health, vol. 2, 2021, article 774308.

  3. Telkkala, Anni, Suvi-Paivikki Sinikumpu, and Laura Huilaja. "Etiology of Adult Female Acne: A Systematic Review." Health Science Reports, vol. 8, no. 5, 2025, article e70697.

  4. Del Rosso, James Q., and Leon Kircik. "The Cutaneous Effects of Androgens and Androgen-Mediated Sebum Production and Their Pathophysiologic and Therapeutic Importance in Acne Vulgaris." Journal of Dermatological Treatment, vol. 35, no. 1, 2024, article 2298878.

  5. Kairey, Lana, Tamara Agnew, Esther Joy Bowles, Bronwyn J. Barkla, Jon Wardle, and Romy Lauche. "Efficacy and Safety of Melaleuca alternifolia (Tea Tree) Oil for Human Health: A Systematic Review of Randomized Controlled Trials." Frontiers in Pharmacology, vol. 14, 2023, article 1116077.

  6. Del Rosso, James Q., and Neal Bhatia. "Status Report on Topical Hypochlorous Acid: Clinical Relevance of Specific Formulations, Potential Modes of Action, and Study Outcomes." Journal of Clinical and Aesthetic Dermatology, vol. 11, no. 11, 2018, pp. 36-39.

  7. Soleymani, S., et al. "The Effect of a Hydrogel Made by Nigella sativa L. on Acne Vulgaris: A Randomized Double-Blind Clinical Trial." Phytotherapy Research, vol. 34, no. 11, 2020, pp. 3052-3062.

  8. Al-Abd, Nazeh M., Zurainee Mohamed Nor, Marzida Mansor, Fadzly Azhar, M.S. Hasan, and Mustafa Kassim. "Antioxidant, Antibacterial Activity, and Phytochemical Characterization of Melaleuca cajuputi Extract." BMC Complementary and Alternative Medicine, vol. 15, 2015, article 385.

  9. Safayhi, H., J. Sabieraj, E.R. Sailer, and H. Ammon. "Chamazulene: An Antioxidant-Type Inhibitor of Leukotriene B4 Formation." Planta Medica, vol. 60, no. 5, 1994, pp. 410-413.

  10. Lan, M., L. Li, S. Luo, J. Chen, X. Yi, X. Zhang, et al. "Emu Oil Enhances Cutaneous Wound Healing by Modulating Inflammation through Promoting Macrophage M2 Polarization via MAPK Signaling Pathway." Journal of Functional Foods, vol. 119, 2024, article 106283.