A frequent and often frustrating challenge encountered in personal skin-care management is the experience of skin sensitivity. Compounding this situation is the notion of how, despite much recent research being directed toward its exploration, much is left unknown regarding this common cutaneous reaction. In addition to providing a review of skin sensitivity, we will explore key approaches toward its management, with a focus on those “sensitive-skin–friendly” cosmeceutical ingredients to consider for inclusion in topical skin-care products directed for both general skin health and reducing the signs of photoaging.

Skin sensitivity is generally defined as the experience of unpleasant skin sensations in response to stimuli which typically should not provoke such sensations. These sensations can vary, but often include pain, burning, stinging, itching, and/or tingling.¹ Symptoms can occur within minutes to hours after exposure to a given trigger, or via a cumulative effect, such as after repeated episodes of applying a topical product.² Objective and subjective forms have been described, with the objective form representing the experience of skin-sensitivity symptoms in conjunction with various clinically evident skin concerns / dermatitis which can alter skin-barrier permeability, such as atopic dermatitis or acne. By contrast, the subjective form represents symptom experience by the patient without observable dermatitis.³ Importantly, skin sensitivity does not involve an immunologic or allergic-based underlying mechanism.⁴ Additional noted elements relating to skin sensitivity include the following:

Prevalence: A survey from the United Kingdom indicated that approximately 51% of women and 38% of men report experiencing sensitive skin; similar rates were found for studies performed in Europe and North America, and global estimates suggest that up to 38% of the world population are affected.⁵

Locations Affected: The most common area affected is the face, in particular the nasolabial fold. Other areas often reported include the volar (front) surface of the forearm, hands, scalp, and genital region.⁶

Common Triggering Factors:^7,8

• Topical cosmetics, skin- and hair-care products (including certain soaps, shampoos, hair products, moisturizers, toners, antiaging creams, sunscreens, and perfumes
• Environmental (including hot or cold temperatures, wind, dry air, humidity, air conditioning, sun exposure, and air pollution)
• Household items (including dishwashing liquid, laundry detergent, and fabric softener)
• Personal-care products (including tampons, menstrual pads, toilet paper, and deodorants/antiperspirants)
• Clothing (including underwear and rough fabrics)

Physiologic changes

Although much work remains to be done toward elucidating the underlying causes of skin sensitivity, several studies have determined two primary skin alterations associated with it, namely disruption of the skin-barrier function and neurosensory dysfunction.^9,10. A disrupted epidermal barrier facilitates the entry of substances capable of triggering local inflammatory mediators which, in turn, induce neurotransmitter-based stimulation of local nerve endings.¹¹ Regarding neurosensory changes, recent research centres around the increased expression of a cellular sensor known as transient receptor potential vanilloid‑1 (TRPV1). Stimulated by the likes of various chemicals, heat, cold, and mechanical changes, TRPV1 may facilitate neurogenic inflammation, pain, and pruritis (itching).^12,13 The table below summarizes these, and related, findings about physiologic changes associated with sensitive skin.¹⁴

 Methods to Limit Experiencing Skin Sensitivity While Using Topical Skin‑care Products

• Prior to using products individually (or in combination) for the first time, consider employing a patch test. Detailed recommendations can be explored with most manufacturers and skin-care professionals, but often involves applying the topical(s) over a small area on the upper inner forearm and leaving the area untouched for at least 24 hours. The product is avoided if any signs of irritation or allergic reaction occur. Such an approach may not predict skin sensitivity or reaction when the product is used over other skin areas and/or for prolonged periods of time.
• Avoid topical products containing ingredients for which there is a known/suspected irritancy or allergy, both through personal experience and that common at a public level. For example, some skin-care retailers add unique labels to highlight those topical products (including those for sensitive skin) which are devoid of common irritants/allergens/etc.
• Ensure the product is labelled for use by those with sensitive skin. To take this a step further, ensure with the product manufacturer that the final product (and not just the individual ingredients independently) has undergone sensitivity testing.
• As best as possible, protect against, limit, and/or avoid common triggers of skin sensitivity (as reviewed above); for example, use of a mineral sunscreen (one indicated to be suitable for sensitive skin) can protect against UV exposure, itself a trigger of sensitivity.
• Avoid/limit use of topical products containing ingredients which increase the penetration of other formula substances deeper into the skin, such as ethanol or propylene glycol.¹⁵
• pH-Balanced skin-care products are designed to support the skin’s own optimal pH level; this promotes optimal skin-barrier maintenance.
• Maintain proper skin hydration (see below).
• Work with your dermatologist to discuss further evaluation options should managing your sensitivity prove to be difficult.

Moisturization and Cosmeceutical Actives to Consider

Many individuals are looking to use topicals for either general skin health and/or to help slow the signs of skin aging; yet sensitivity reactions can interfere with the ease of their integration. Understandably, for those excited to use a recently purchased topical product, it can be very disappointing to discover that it triggers a skin reaction. What follows are examples of cosmeceutical ingredients often formulated into topicals designed for sensitive skin, including moisturizers, serums, cleansers, sunscreens, among others. As we will explore, evidence suggests their inclusion in such topicals may help mitigate against the experience of skin-sensitivity symptoms.

Ceramides and Physiologic Moisturizers

As reviewed above, an altered skin barrier may “open the floodgate” toward allowing triggering factors deeper into the skin tissue and stimulate symptoms of skin sensitivity. As such, methods to fortify the barrier are essential in limiting this occurrence. Physiologic moisturizers can be an excellent starting point as they—in comparison to nonphysiologic counterparts—typically contain those lipids found in the skin’s lipid-matrix component of the barrier. These include ceramides, sources of fatty acids, and cholesterol. A variety of studies have demonstrated the ability of such moisturizers to restore skin-barrier integrity in the context of various dermatoses.^{16,17,18,19,20} Although most trials have explored the use of ceramide-based moisturizers in managing dermatoses such as atopic dermatitis, acne, rosacea, and dry skin, some research is beginning to incorporate its effects on one form of sensitive skin known as cosmetic-intolerance syndrome. A manufacturer-funded study enrolled 50 male and female subjects exhibiting mild to moderate atopic dermatitis or other pruritic dermatoses (including cosmetic-intolerance syndrome).²¹ The participants applied a moisturizing cream three times daily for four weeks. In addition to being centred around a pseudoceramide (ceramide-like structure also found to improve the skin barrier), the moisturizer also contained agents to mitigate against inflammation. Compared to baseline levels, investigator assessments (such as for irritation, erythema, roughness) significantly improved for all participants by the study’s end (p < 0.0001). Subjective assessment also proved beneficial, with significant improvements being reported (for skin characteristics such as redness, irritation, and overall assessment) at both the 2- and 4‑week marks (p < 0.001). Objective instrumental measures demonstrated significant improvements by 4 weeks for the likes of skin hydration (p < 0.0001) and skin smoothness (p < 0.0001), while approaching significance for a reduction in transepidermal water loss (TEWL) (p = 0.0363), a measure which reflects water loss through the skin.²²

Panthenol

Several agents are used in topical formulas for the purposes of providing a skin-soothing effect. In the case of panthenol, in addition to functioning as a moisturizing agent and providing support to the barrier’s lipid-matrix production,²³ it has also been demonstrated to reduce the potential for other substances within a formula from themselves triggering skin irritation.²⁴ An example of this is research showing how, when panthenol was added to a test formula containing sodium lauryl sulfate (SLS; a known skin irritant in high concentration), it was found to reduce the degree of SLS‑induced skin redness, warming, tingling, and stinging, among others.²⁵

Allantoin

Another popular substance added to sensitive-skin formulas is that of allantoin, derived originally from the comfrey plant (Symphytum officinale). Utilized for its skin-soothing and ‑protective properties, it is thought to augment barrier functioning through enhancing the skin’s water-binding capacity.²⁶ It has also demonstrated antioxidant and anti-inflammatory effects. ^27,28,29

Bakuchiol

A common challenge for those with, or even without, sensitive skin looking to use a topical retinoid to reduce the appearance of skin-aging signs, such as wrinkling and uneven skin tone, is the experience of skin irritation. This explains why a gradual concentration-escalation strategy is employed when using retinoids.³⁰ A cosmeceutical gaining interest for its ability to function like retinol, in terms of its ability to regulate gene expression relating to collagen production, yet also demonstrate a high degree of tolerability, is that of bakuchiol. A compound derived from the seeds of the plant Psoralea corylifolia (babchi), among other plant sources, it has demonstrated anti-inflammatory and antioxidant activities.³¹ Previous human study has demonstrated a similar positive effect between retinol and bakuchiol in terms of reducing the appearance of fine wrinkles and hyperpigmentation.³²Another recent 4‑week, manufacturer-funded trial sought to specifically explore bakuchiol’s effects on sensitive skin, in addition to skin appearance. Here, 60 female subjects aged 40–65 applied a 1% bakuchiol-containing moisturizer to the face and neck twice daily. As a method for studying the effects on sensitive skin, investigators enrolled subjects experiencing atopic dermatitis / eczema, rosacea, and cosmetic-intolerance syndrome, each comprising one-third of all subjects. Evaluation measures included both investigator- and subject-based tolerability and efficacy assessments, as well as instrumental evaluation of skin hydration and TEWL. Authors reported how, overall, the subject-based tolerability assessment demonstrated excellent results in relation to the absence of stinging, burning, itching, and tightness (no p value provided by authors). Only 10% of subjects, mostly those with eczema, reported stinging on product applications which persisted into week 4. Authors speculate how this may relate to a notable degree of barrier damage typical in this population. Investigator-based assessments for tolerability and efficacy showed significant improvements after 4 weeks for the likes of visual and tactile smoothness, clarity, radiance, overall appearance, and global antiaging effects (all p < 0.001). These results for efficacy were mirrored in the subject-based assessments (all p < 0.001). No changes were found for TEWL. However, a significant 16% increase in skin hydration was noted p < 0.001).³³ Together, these offer encouraging evidence showcasing the skin-supportive benefits of bakuchiol by those with sensitive skin looking to reduce the signs of facial skin aging.

Conclusion

Although the experience of sensitive skin can be frustrating, research has helped shed light into methods by which various lifestyle approaches can limit its severity. Advancements in formulating of topical products, including both the omission of irritant ingredients and addition of skin-soothing cosmeceutical agents, has helped usher in a wider range of products better tolerated by those with sensitive skin.