Reactive arthritis (ReA) belongs to a group of related disorders known as seronegative spondyloarthritis, which have common radiological and clinical features associated with the genetic risk factor HLA-B27. ReA is an inflammatory arthritis which occurs as an immunomodulated sterile inflammatory response to infection and occurs at a site away from the primary infection, most commonly 1 to 4 weeks after infection. It typically occurs in the younger population, with peak between the ages of 20 and 29, and is more common in Caucasians and males. Reactive arthritis is most often preceded by infection of the gastrointestinal (GI) or genitourinary (GU) tract. The most common pathogens in the GI tract are Sallmonella, Shigella and Campylobacter, and in the GU system Chlamydia trachomatis. The clinical picture consists of asymmetric oligoarthritis, mostly of the lower extremities, enthesitis, dactylitis and extraarticular symptoms such as conjunctivitis, iritis, urethritis, carditis, conduction disturbances and various mucocutaneous lesions. Due to the classic triad of symptoms (which occurs in only 30% of cases) of arthritis, urethritis and conjunctivitis, ReA is also known as Reiter's syndrome. The diagnosis is based on a previous infection and a characteristic clinical picture. Since there is no causal therapy for ReA, the goal of treatment is to alleviate symptoms and prevent chronic complications of the disease. In the treatment, it is primarily necessary to eradicate the cause of active infection, and then nonsteroidal antirheumatic drugs, analgesics, glucocorticoids and immunosuppressants are used. In addition to treatment, prevention is important, which we will achieve by educating young sexually active people about practicing safe relationships to avoid sexually transmitted diseases, which are one of the causes of reactive arthritis. The prognosis of ReA is good in most cases, although in 30-63% of individuals the disease progresses to chronicity.