Granuloma Annulare: What Is This Ring-Shaped Red Rash? Causes, Appearance and Treatment

Granuloma Annulare (GA) is a non-infectious inflammatory skin condition marked by red or skin-colored rashes arranged in rings, most often on the backs of the hands, the tops of the feet or the trunk. It is not contagious and is usually harmless, but in some people it may be associated with systemic conditions such as diabetes or abnormal blood lipids. In this article, a dermatologist explains the types, symptoms and treatment approaches for GA.

What causes Granuloma Annulare?

GA is an inflammatory skin reaction that is not caused by infection. The exact mechanism is not fully known, but in some people it is associated with systemic conditions, particularly diabetes and abnormal blood lipids, especially in the generalized type. This is why a doctor may recommend additional tests for certain patients.

Types and symptoms of Granuloma Annulare

• Localized GA: The most common type, appearing as red or skin-colored rings on the backs of the hands and feet.

• Generalized GA: A rash spread across the body, more often linked to other systemic conditions or diabetes than the localized type.

• Subcutaneous GA: Seen in children, appearing as lumps under the skin that resemble a rheumatoid nodule.

In general, the bumps or rashes of GA are flat, not itchy and not especially painful. The main concern is therefore usually cosmetic rather than physical discomfort, and some rashes may clear on their own within about 2 years.

Treatment of Granuloma Annulare

Treatment depends on the type and severity. The medicines and methods below are based on dermatology clinical practice guidelines.

• Localized GA that is not bothersome: If it causes no trouble, it may be enough to monitor it and wait for it to clear on its own.

• When treatment of the area is wanted: Topical or intralesional steroids (steroid creams or injections into the lesion) or cryotherapy (freezing) for a single patch may be used.

• Generalized GA: Hydroxychloroquine, dapsone, isotretinoin or PUVA phototherapy may be considered.

Because some of the medicines used for generalized GA have side effects that need monitoring, they should always be used under the care of a dermatologist.

Frequently asked questions

Is Granuloma Annulare dangerous or contagious? GA is a non-infectious inflammatory skin condition and is not contagious. It is generally not dangerous, but in some people it may be associated with diabetes or abnormal blood lipids, especially the generalized type.

Can a GA ring-shaped rash go away on its own? Some GA rashes may clear on their own within about 2 years, especially the localized type that is not bothersome, where monitoring alone may be enough.

How is Granuloma Annulare treated? The localized type may be treated with topical or intralesional steroids or cryotherapy. The generalized type may be treated with hydroxychloroquine, dapsone, isotretinoin or PUVA phototherapy, under a doctor's care.

How is GA different from ringworm? Although both cause ring-shaped rashes, GA is not caused by a fungus, is not contagious and is usually not itchy, whereas ringworm is caused by a fungus and often has scaling and itching. A definite diagnosis should be made by a dermatologist.

If you have a ring-shaped rash that does not go away or suspect Granuloma Annulare, you should get a proper diagnosis. Consult a dermatologist at Siam Dermatology, phone +66 61 448 7000 or LINE @siamderm.

Written by Dr. Patara Voravutinon, Dermatologist · Last reviewed July 16, 2026