The sebaceous glands create an oily substance called sebum. Sebum lubricates the dog’s skin. Without sebum, the dog’s skin would be dry and flaky. The secretions move through ducts from the sebaceous glands into hair follicles. Sebaceous cysts occur when the follicle gets obstructed.
Sebaceous cysts are usually smooth, round growths that are about 5 mm to 5 cm in diameter. Some have a slightly bluish tint. Unless the cysts get really big, they don’t hurt.
Most sebaceous cysts will go away on their own. In some cases, warm soaks or hot packs may be needed to speed up this process.
Some of these cysts will rupture, releasing the greyish white or brown, cheese-like
discharge. If a rupture occurs, it usually will heal on its own. If a rupture doesn’t heal, the cyst can be removed surgically — or it may be treated medically with antiseptic rinses, antibiotic ointments, and corticosteroid ointments.
If a large cyst fills repeatedly, a general anaesthetic and surgical excision may be required.