Potassium bromide again is well known to be surprisingly effective in patients with severe myoclonic epilepsy in infants (SME). Rare side effects on the skin reappeared, such as the febrile nodular panniculitis (Weber-Christian syndrome). In 1993 we described the first three cases of necrotizing panniculitis and introduced the term 'halogen panniculitis'. It is a systemic disease with crops of subcutaneous nodules, fever, elevated sedimentation rate, hepatosplenomegalia, and abdominal pain. Later severe necrosis of the skin and adipose tissue may happen with deep ulcerations. History and course of five cases, described in this paper, suggest either an allergy or toxic reason. Histologic picture shows inflammation of adipose tissues with infiltrating lymphocytes, but lymphocyte transformation test (LTT) was not reliable in diagnosing the disease. Possibly, bromides act as a chemokine and stimulate inflammatory processes. Bromide can be transformed into a bromine radical/free electron pair under UV irradiation at 228.8 nm in aqueous solution. The bromine radical may have detrimental effects on the tissue. However, despite some research, the origin of halogen panniculitis and similar diseases remains unclear.