Azelaic Acid: Can It Help If My Scalp Is Irritated or Oily?

Azelaic acid is a compound that has gained attention in dermatology for its multiple benefits in skin care. Originally used in the treatment of acne and rosacea, its application has expanded to scalp care, especially in cases of irritation and excessive oil production. This article explores how azelaic acid can be useful in addressing these concerns, based on scientific research and clinical studies.

What is Azelaic Acid?

Azelaic acid is a nine-carbon dicarboxylic acid naturally found in cereals such as wheat, barley, and rye. It has been used for years in dermatology due to its antimicrobial and anti-inflammatory properties, making it effective in treating skin conditions such as acne vulgaris and rosacea. Its ability to inhibit bacterial proliferation and reduce inflammation makes it a valuable therapeutic agent in various skin disorders. Additionally, its role as a regulator of cell growth has sparked interest in its potential use in skin and scalp-related conditions.

Scalp Diseases and Their Relationship with DHT

The scalp can be affected by various conditions, some of which are linked to the hormone dihydrotestosterone (DHT), while others are not. Among the most common are androgenetic alopecia, alopecia areata, seborrheic dermatitis, and folliculitis.

Androgenetic alopecia is one of the most common forms of hair loss and is directly related to DHT's action on hair follicles. This hormone shortens the hair growth phase and reduces follicle size, eventually leading to miniaturization and permanent hair loss. On the other hand, alopecia areata is an autoimmune disease in which the immune system attacks hair follicles, causing patchy hair loss.

Other scalp conditions are not directly linked to DHT but can still influence hair health. Seborrheic dermatitis is a chronic inflammation that causes redness, flaking, and excessive sebum production, contributing to an unhealthy environment for hair growth. Folliculitis, on the other hand, is an inflammation of hair follicles usually caused by bacterial or fungal infections, which can lead to sensitivity, itching, and even temporary hair loss.

Azelaic Acid and Scalp Health

The scalp, like facial skin, can be affected by various conditions that cause irritation and excessive sebum production. Among the most common scalp diseases are seborrheic dermatitis, folliculitis, psoriasis, and tinea capitis. These conditions can cause inflammation, flaking, itching, and, in some cases, contribute to hair loss.

Seborrheic dermatitis is a chronic inflammatory condition that affects body areas with higher sebum production, including the scalp. It is characterized by redness, flaking, and an itching sensation. Azelaic acid may be beneficial in this case due to its anti-inflammatory properties and its potential to regulate sebum production.

On the other hand, folliculitis is an infection of the hair follicles caused by bacteria or fungi. It manifests as red or pus-filled bumps that can be painful and cause inflammation. Some studies have suggested that azelaic acid has antimicrobial properties that could help control such infections.

Scalp psoriasis is another common condition, characterized by the accelerated accumulation of skin cells forming thick, scaly plaques. Although azelaic acid is not a conventional treatment for psoriasis, its keratolytic action could help reduce the buildup of dead cells and improve the appearance of affected skin.

Finally, tinea capitis is a fungal infection that causes hair loss patches, flaking, and redness. While azelaic acid has antimicrobial properties, its effectiveness against the fungi responsible for tinea capitis has not been specifically studied, so standard treatment remains antifungal medications.

The application of azelaic acid on the scalp has been studied to determine its effectiveness in managing these conditions. Additionally, its keratolytic effect—its ability to promote cell renewal by eliminating dead cells—could play a crucial role in scalp health by preventing follicular obstruction.

Anti-Inflammatory Properties

Scalp inflammation can result from various factors, including seborrheic dermatitis, folliculitis, and other inflammatory conditions. Azelaic acid has been shown to have significant anti-inflammatory properties. A study published in 2020 in the journal Frontiers in Pharmacology investigated the effect of azelaic acid on hair growth in mice. Although the primary goal was to assess hair growth, researchers observed that azelaic acid reduced scalp inflammation, suggesting potential benefits for inflammatory conditions.

This study, conducted in 2020, employed a topical application method in laboratory mice. Improvements in scalp inflammation were observed, indicating a possible reduction in inflammatory responses that can trigger hair problems. However, the study's exact duration was not specified in the available summary. While the findings are promising, the main criticism of this study is that the tests were conducted on animals, which does not guarantee the same results in humans. Further clinical trials in humans are necessary to evaluate its effectiveness in patients with inflammatory scalp conditions.

A more recent study, published in Experimental Dermatology in 2023, explored the effects of azelaic acid on human keratinocyte cell cultures. Researchers found that azelaic acid reduced the expression of inflammatory mediators such as interleukin-6 (IL-6), a key molecule in skin inflammation. The analysis was conducted in vitro on human epidermal cell cultures, and although the results showed a decrease in inflammation markers, it is important to consider that in vitro studies do not always accurately reflect how a substance behaves on live human skin. This study also did not specify the exact duration of the experiments.

Sebum Regulation

Excess sebum on the scalp can lead to a greasy appearance and contribute to conditions such as seborrheic dermatitis and acne. Azelaic acid has been studied for its ability to regulate sebum production. A study published in Dermatologic Therapy in 2021 evaluated the effect of a 20% azelaic acid chemical peel on sebum production in acne patients. The results showed a significant decrease in sebum production after a series of six treatments, suggesting a prolonged sebostatic effect.

This research, conducted in 2021, involved the application of a 20% azelaic acid solution as a chemical peel. Twenty-seven women aged 19 to 25 with a diagnosis of acne vulgaris participated. Six treatments were performed throughout the study, although the specific duration was not mentioned. A critical aspect of this study is the relatively small sample size and the fact that it focused on facial skin. While the results indicate a seboregulatory effect, further research is needed to determine whether these effects can be replicated on the scalp and in a broader population.

User Experiences

Azelaic acid has been discussed in the hair loss community as a potential treatment for scalp irritation and oiliness. Many users have shared their experiences with this ingredient, which is often found in skincare products but has been explored for its effects on the scalp.

Some users report that azelaic acid has helped reduce scalp oiliness. They describe it as having a mild sebum-regulating effect, leading to a less greasy scalp over time. A few individuals mention using azelaic acid in combination with other treatments like ketoconazole shampoo or topical finasteride, and they believe it contributes to an overall improvement in scalp health. However, some users have noted that the effects take time to become noticeable, requiring consistent application.

Other users focus on its anti-inflammatory properties. Those dealing with redness, itching, and irritation find that azelaic acid provides some relief, especially when used in lower concentrations. Some users compare it to ingredients like niacinamide or zinc pyrithione, which also help with scalp irritation. A few people with seborrheic dermatitis or mild dandruff say that azelaic acid helps calm their symptoms, though not as effectively as medicated antifungal treatments.

However, not everyone has a positive experience. Some users report that azelaic acid initially caused dryness or mild peeling, especially when applied in high concentrations. A few individuals mention experiencing a temporary increase in scalp irritation before their skin adjusted to the treatment. There are also concerns about potential interactions with other treatments, as some users feel azelaic acid might weaken the effects of minoxidil when applied together.

Overall, the community feedback on azelaic acid for scalp irritation and oiliness is mixed but generally leans positive. Users who benefit from it often incorporate it as part of a broader scalp care routine rather than relying on it as a standalone solution. Those with sensitive skin or pre-existing conditions should consider starting with a lower concentration to minimize irritation.

Final Considerations

Azelaic acid shows promising potential in treating scalp irritation and excessive oiliness. Additionally, its possible influence on DHT-related diseases and inflammatory conditions makes it an interesting option.

However, more clinical studies in humans are needed to validate these effects. As with any dermatological treatment, consulting a healthcare professional before incorporating it into a scalp care routine is recommended.

References

Nazzaro-Porro, M., & Passi, S. (1991). Azelaic acid. A review of its pharmacological properties and therapeutic efficacy in acne and hyperpigmentary skin disorders. PubMed. Retrieved from https://pubmed.ncbi.nlm.nih.gov/1712709/ PubMed

Thiboutot, D., & Weiss, J. (1996). Efficacy and safety of topical azelaic acid (20 percent cream): an overview of results from European clinical trials and experimental reports. PubMed. Retrieved from https://pubmed.ncbi.nlm.nih.gov/8654128/​ PubMed

Giannotti, B. (1989). [Validity of azelaic acid in the therapy of acne. Long-term clinical results]. PubMed. Retrieved from https://pubmed.ncbi.nlm.nih.gov/2534553/​ PubMed

Medical Dialogues. (s.f.). Azelaic acid: Indications, Uses, Dosage, Drugs Interactions, Side effects. Retrieved from https://medicaldialogues.in/generics/azelaic-acid-2726143​ medicaldialogues.in

Brooks, M. (2015). FDA OKs Azelaic Acid (Finacea) for Papulopustular Rosacea. Medscape. Retrieved from https://www.medscape.com/viewarticle/848933​ Medscape