From Symptoms to Signaling Pathways in Seborrheic Dermatitis

Seborrheic dermatitis (SD) is commonly encountered in dermatology practice, yet it is often underestimated in terms of its chronicity, underlying biology, and impact on patients’ quality of life. Although SD is frequently described as a mild condition, many patients experience persistent symptoms, visible facial involvement, and recurrent flares that can significantly affect daily functioning and self-perception.

This topic was explored in a recent Dermatology Times DermView custom video series featuring Christopher G. Bunick, MD, PhD, and Benjamin Ungar, MD, who examined evolving perspectives on the pathophysiology and management of SD. The conversation highlighted how growing recognition of SD as a chronic inflammatory disease may influence treatment decisions, including the role of nonsteroidal topical therapies and targeted anti-inflammatory approaches.

Disease Burden vs Clinical Perception

Although SD is often labeled as mild, Ungar and Bunick noted that its real-world impact can be significant, particularly when lesions affect highly visible areas such as the face and scalp. Even limited disease can meaningfully disrupt quality of life.

“One of the things that we’ve learned across inflammatory skin diseases is how dramatically quality of life can drop with even small increases in symptoms,” one clinician noted, adding that a single erythematous, scaly patch can cause outsized psychosocial distress for patients.

Patients frequently describe embarrassment, frustration, and the perception that others view them as unclean. Many report increasing washing or grooming behaviors in an attempt to control the condition, often unsuccessfully.

These experiences underscore the need to recognize SD not merely as a cosmetic nuisance but as a chronic inflammatory disease with meaningful patient burden.

Limitations of Static Severity Staging

Traditional severity labels—mild, moderate, severe—may also obscure the true impact of SD. Bunick and Ungar emphasized that staging based solely on lesion extent can miss important elements such as symptom burden, recurrence, and treatment resistance.

The clinical phenotype itself is variable. SD can affect the scalp, eyebrows, beard area, ears, chest, and intertriginous regions, with presentations varying across age groups and skin types. This variability complicates staging and reinforces the need for individualized treatment decisions rather than rigid treatment algorithms.

Reconsidering Pathophysiology

Historically, SD has been framed primarily as a yeast-driven disorder. However, newer molecular and transcriptomic research suggests the underlying biology is more complex.

Inflammatory signaling—particularly involving T helper 17 cells and IL-22 pathways—appears to play a central role. As Bunick explained, yeast colonization may be more accurately viewed as a downstream effect of inflammation and barrier dysfunction rather than the primary driver of disease.

This distinction has therapeutic implications. Antifungals may reduce microbial load but do not directly address inflammation or barrier impairment. Similarly, prolonged topical corticosteroid use can present limitations, particularly on the face, where long-term steroid exposure is undesirable.

When to Consider Advanced Therapy

For most patients, SD can be controlled with topical therapies. However, a subset of patients experience persistent or widespread disease despite conventional treatment.

Although no biologics are currently approved specifically for SD, clinicians noted that growing knowledge of inflammatory signaling pathways raises the possibility of biologic approaches in severe or refractory cases—particularly when SD overlaps with other inflammatory conditions such as psoriasis or atopic dermatitis.

The panel emphasized that timing matters. Escalation should be considered in the following cases:

• Disease remains uncontrolled despite optimized topical therapy
• Quality of life is significantly affected
• Frequent flares require repeated corticosteroid use

Choosing Among Emerging Therapies

As targeted therapies expand across dermatology, clinicians increasingly face the challenge of selecting among multiple mechanisms of action. During the discussion, clinicians highlighted the role of PDE4 inhibition as one strategy for addressing SD’s inflammatory component. A topical PDE4 inhibitor foam evaluated in clinical trials demonstrated meaningful efficacy in moderate disease.

In a phase 3 vehicle-controlled study, approximately 43% of patients achieved Investigator Global Assessment (IGA) success at 8 weeks compared with 25% in the vehicle group. Rapid improvements were also observed, with approximately 73% of treated patients reaching IGA success at 4 weeks in some analyses. Longer-term extension data suggest durable control. In an open-label extension study, 76% to 80% of patients achieved or maintained clear or almost clear skin (IGA 0-1) at weeks 24 through 52.

Long-Term Management

Another recurring theme in the discussion was the importance of patient education. SD is a chronic disease, and successful management often requires ongoing treatment rather than short courses of therapy. Clinicians highlighted the need to establish realistic expectations early, explaining that therapy aims to control inflammation and maintain remission rather than cure the disease.

The Case for Early Intervention

Finally, the panel underscored the potential advantages of treating SD early in its course. Earlier treatment may reduce inflammatory burden, improve quality of life, and prevent the cycle of flare and relapse that many patients experience. Although long-term outcome data remain limited, clinicians agreed that prompt control of inflammation is unlikely to have downsides—and may ultimately improve the trajectory of disease.

Looking Ahead

As understanding of SD biology advances, the therapeutic approach is evolving from symptom suppression to targeted inflammation control. For clinicians, this shift reinforces the importance of individualized treatment strategies, early intervention, and thoughtful integration of emerging therapies into long-term disease management.