The world of chemical exfoliation has long been dominated by salicylic acid when it comes to treating blemishes, oily skin and clogged pores. However, there is a lesser-known member of the beta hydroxy acid (BHA) family that may offer a gentler but effective alternative. Trethocanic acid has been quietly amassing fans for its pore-clearing abilities with less irritation. In this article we explore how trethocanic acid works, how it compares with other BHAs and the best way to use it in your routine.
What is Trethocanic Acid?
Trethocanic acid is a BHA that was initially developed to lower cholesterol. It works similarly to salicylic acid by penetrating into the pores to dissolve excess sebum and exfoliate from within. Like other BHAs, it is oil-soluble, which makes it particularly useful for managing acne, blackheads and congested skin. What sets trethocanic acid apart is that it delivers exfoliation with a lower risk of irritation.
Although originally developed in the early 2000s, trethocanic acid stayed under the radar in skincare until recently. It is now starting to appear in formulations aimed at mild exfoliation with skin barrier support. This offers a middle ground between effectiveness and tolerance. As such, it could be a useful option for those who need pore-level exfoliation but cannot tolerate traditional BHAs. Its key benefits include:
- Minimal irritation: Thanks to its gentle nature, trethocanic acid minimises the risk of irritation, dryness and flakiness. This makes it suitable for everyday use and even for sensitive skin.
- Gentle exfoliation: Trethocanic acid offers more controlled, gentle exfoliation. This makes it an excellent option for those new to chemical exfoliants or with reactive skin conditions like rosacea.
- Reduced pore congestion: Like salicylic acid, trethocanic acid penetrates the pores to clear impurities and reduce congestion. This helps reduce the appearance of sebaceous filaments and prevent blackheads and future breakouts.
- Smoother and brighter complexion: By gently removing dead skin cells, trethocanic acid can create a smoother texture. It may also help brighten and even out the skin.
What’s the Difference Between Trethocanic Acid and Salicylic Acid?
Whilst both fall under the BHA category, trethocanic acid and salicylic acid differ in a few ways. The main differences come down to how they perform, who they suit and how they interact with the skin barrier:
- Molecular structure and mechanism: Both are oil-soluble and penetrate the pores to dissolve sebum and loosen dead skin cells. However, trethocanic acid has a different structure that results in a milder exfoliating effect. This makes it more useful for sensitive skin without sacrificing the key benefits of a BHA.
- Exfoliating strength: Salicylic acid is known for its strong keratolytic action and is effective for moderate to severe acne. Trethocanic acid offers gentler, lower-intensity exfoliation that supports smoother texture and clearer pores over time, with fewer risks of dryness or peeling.
- Tolerability: Salicylic acid can trigger irritation, especially in dry or reactive skin. Trethocanic acid is potentially a more barrier-friendly alternative. This may make it a better fit for sensitivity, mild rosacea or conditions like eczema where harsher acids are unsuitable.
- Anti-inflammatory properties: A large body of research supports salicylic acid’s anti-inflammatory properties. Trethocanic acid seems likely to share this property, but more research is needed to confirm it.
How Do You Use Trethocanic Acid in Your Skincare Routine?
Although there are fewer products with trethocanic acid than with salicylic acid, it is slowly gaining traction. You may need to check the ingredients list, as the product is often labelled simply as containing “BHAs” given its lack of name recognition. Here are our top tips:
- Choose the right product: Look for leave-on formulations such as serums or toners. Gel or watery formulas tend to work best for combination or oily skin, whilst hydrating lotion bases suit dry or sensitive types.
- Frequency: Most skin types can tolerate trethocanic acid several times a week or even daily. Start with 2 to 3 times per week and build up or reduce based on how your skin responds.
- Pairing: Trethocanic acid works well alongside hydrating, barrier-supportive ingredients like hyaluronic acid, niacinamide and ceramides. You can also layer it with strong actives like vitamin C, with less risk of irritation than stronger BHAs. Just avoid pairing it with other exfoliants in the same step.
- Application: Apply after cleansing and before serums or moisturiser, morning or evening. Always follow with a broad-spectrum sunscreen of at least SPF 30, as even gentle acids can increase sensitivity to sun damage.
Is Trethocanic Acid Safe?
Although trethocanic acid shows promise as a gentle BHA, it is a less commonly used ingredient. There is less data on its safety and efficacy, so proceed with some caution. A few points to consider before adding it to your routine:
- Milder exfoliation: Whilst this benefits sensitive skin, if you have normal skin you may prefer salicylic acid or a combination of AHAs and BHAs for more intense exfoliation.
- Limited research: As a newer ingredient, trethocanic acid lacks the extensive research that salicylic acid enjoys. As more brands and dermatologists explore it, we can expect more data on its effectiveness and safety.
- Availability: Because it is relatively new, trethocanic acid is not yet as widely available as salicylic acid. You may need to seek out specialist brands or newer retailers.
If you do go ahead, remember that whilst it is gentler, it is not risk free. Trethocanic acid still has the same potential side effects as salicylic acid, including flakiness, dryness, irritation and purging. Always do a patch test with any new ingredient to check for allergy, and start slowly before building up frequency as your skin tolerates it. As always, if you have any existing skin or health conditions, reach out to a dermatologist or your health provider before introducing any new products.
Trethocanic acid might be the gentler BHA that sensitive skin types have been waiting for. It can deeply penetrate and cleanse pores without the harshness of salicylic acid. This brings exfoliating benefits to a wider range of skin types. It is relatively new and still uncommon in skincare, so only time will tell whether it becomes a staple or remains a niche favourite.
At City Skin Clinic, we are passionate about personalised skincare. Our online skin clinic offers safe and effective custom skincare treatments. Where appropriate our doctors use ingredients such as tretinoin and hydroquinone to treat skin conditions like acne, hyperpigmentation, melasma and skin ageing. To start your personalised skincare plan, book a virtual video consultation or use our online consultation form. The journey towards great skin starts here.
This article is intended for general informational purposes only and is not a substitute for medical advice, diagnosis or treatment. Always consult a qualified medical provider for any medical concerns or questions you might have.
