Acne conglobata is an uncommon but severe form of acne associated with the development of multiple nodules and cysts that are so numerous that they join beneath the skin surface giving rise to large areas of painful, tender swelling. It usually affects the face but can also affect the chest and back.

Acne conglobata can lead to severe scarring over the counter treatments and topical treatments on their own are ineffective and it will usually require a powerful oral medication such as isotretinoin prescibed by a dermatologist to get control. In some cases steroid tablets (prednisolone) may be used in conjunction with isotretinoin to reduce inflammation.