Serum sickness is immune response to a foreign antigen, usually a heterologous protein. Incidence rate is less than 0.5%. Antigens and responding antibodies form circulating immunocomplex that is characteristic for serum sickness. The condition occurs 7-15 days after exposure to the antigen, usually with clinical picture of glomerulonephritis. The immunocomplex circulates to other tissues where it sediments and causes inflammation, such as arteritis, neuritis, synovitis. The aim of this research is to present the break out of serum sickness in form of anterior uveitis due to azithromycin therapy administered by mouth. Identifying of anterior uveitis may help in early diagnostics and treatment of serum sickness.