CONDITION
Sebaceous Adenitis
Sebaceous adenitis is an inflammatory condition affecting the sebaceous glands in the skin — the small structures that produce oils to keep the coat and skin supple. In this condition, the body's immune system appears to target these glands, leading to their gradual destruction. The result is skin that becomes dry, scaly, and less able to maintain its normal protective barrier. Owners often notice changes in coat quality first: the fur may become dull, brittle, or matted, with white or silver scales clinging to the hair shafts, particularly along the back, head, and ears. Some dogs develop patchy hair loss, a musty odour, or areas where the skin feels thickened. The pattern and severity vary considerably between individuals, and in some cases the changes are subtle and slow to develop. This page explores what sebaceous adenitis may look like in practice, the processes thought to drive it, how veterinary surgeons investigate and confirm it, and the range of approaches used to manage skin health over time.
Why this matters now
Sebaceous adenitis typically develops in young adult dogs, most commonly between 1 and 5 years of age. However, onset can occur at any age. The condition is often first noticed as subtle coat changes that progressively worsen.
The disease tends to be slowly progressive without treatment. Early stages may show only minor scaling and dull coat, but advanced cases can develop extensive hair loss, thickened skin, and secondary infections. Some dogs experience cyclic improvement and worsening. Response to treatment varies considerably between individuals.
Signals & patterns
Early signals
Dull, dry coat
The coat may lose its normal sheen and feel coarser or more brittle than usual.
White or silver scaling
Fine scales may appear along hair shafts, particularly visible in dark-coated dogs.
Hair that clumps or mats easily
Without normal sebaceous secretions, hair may stick together in small clumps.
Subtle thinning on the head or ears
Hair loss often begins in specific areas before becoming more generalised.
Later signals
Follicular plugging
Keratinous material accumulates around hair follicles, creating a characteristic "follicular cast" appearance.
Symmetrical hair loss
In Standard Poodles, hair loss typically affects the head, ears, and dorsum in a symmetric pattern.
Thickened, wrinkled skin
The skin may become hyperpigmented and develop a thickened, corrugated texture.
Secondary bacterial infections
Without protective sebum, the skin becomes more susceptible to bacterial overgrowth.
Click to read about the biological mechanisms
How this is usually investigated
Diagnosis of sebaceous adenitis requires skin biopsy to demonstrate the characteristic glandular inflammation and destruction.
Skin biopsy
Clinical examination
Skin cytology
Trichogram
Options & trade-offs
Management of sebaceous adenitis focuses on replacing lost skin oils, controlling scaling, and managing secondary complications.
Oil therapy
Topical oil soaks (often using mineral oil or proprietary products) help replace lost sebum and soften keratinous debris.
Trade-offs: Labour-intensive, requiring regular application and thorough bathing. Often forms the cornerstone of management.
Keratolytic shampoos
Medicated shampoos help remove scale and follicular plugs.
Trade-offs: Requires regular use. Different formulations suit different dogs.
Fatty acid supplementation
Omega fatty acids may support skin barrier function and reduce inflammation.
Trade-offs: Benefits vary between individuals. Usually part of multimodal management rather than sole therapy.
Immunomodulatory therapy
Ciclosporin or other immunomodulators may help in some cases by reducing the immune attack on sebaceous glands.
Trade-offs: May slow progression but cannot restore already-destroyed glands. Requires monitoring for side effects.
Antibiotic therapy
May be needed to treat secondary bacterial skin infections.
Trade-offs: Addresses secondary complications but not the underlying condition.
Common misconceptions
"Sebaceous adenitis is a type of allergy."
Sebaceous adenitis is an autoimmune condition targeting sebaceous glands, not an allergic response to environmental or food triggers.
"The condition is contagious."
Sebaceous adenitis is not infectious and cannot be transmitted between dogs or to humans. It has a genetic basis in affected breeds.
"Treatment can cure the condition."
Management can significantly improve coat quality and comfort, but destroyed sebaceous glands do not regenerate. Ongoing management is typically needed.
Related conditions
Atopic Dermatitis in Dogs
Atopic dermatitis shares with sebaceous adenitis the feature of chronic immune-mediated skin inflammation, though the trigger differs—environmental allergens in atopic dermatitis versus the sebaceous glands themselves in sebaceous adenitis. Both conditions can produce scaling, altered coat quality, and secondary skin infections, and distinguishing between them often relies on biopsy findings and the pattern of change over time.
Hypothyroidism in Dogs
Hypothyroidism can produce skin changes that overlap with those seen in sebaceous adenitis, including a dry, brittle coat, scaling, and patchy hair loss. In some cases, hypothyroidism may coexist with or contribute to sebaceous gland dysfunction, and thyroid testing is often considered during the investigation of chronic skin disease in dogs.
Cushings Disease in Dogs
Cushing's disease affects skin structure and coat quality through chronic elevation of cortisol, leading to thinning, fragility, and poor regrowth that can resemble some features of sebaceous adenitis. Both conditions may present with coat changes and skin that feels altered in texture, though the underlying mechanisms and broader clinical patterns differ.
Otitis Externa in Dogs
Dogs with sebaceous adenitis often develop secondary bacterial or yeast infections of the skin due to disruption of the normal protective barrier, and the same process can affect the ear canals, leading to otitis externa. The two conditions may occur together, particularly in individuals with widespread skin involvement.
Pemphigus
Pemphigus represents another form of immune-mediated skin disease, though it targets the connections between skin cells rather than the sebaceous glands. Both conditions involve the immune system acting against skin structures, and biopsy with histopathology is often used to distinguish between them when crusting, scaling, or erosions are present.
Understanding the hereditary nature of sebaceous adenitis in predisposed breeds provides important context. Learning about the typical grooming and management routines involved can help owners prepare for the commitment required. Documenting coat changes over time with photographs may provide useful information for your veterinary team.
Last reviewed: 24 April 2026 · Dr Alastair Greenway MRCVS