Most patients with severe acute pericarditis should be hospitalized for complete diagnosis and observation for complications, particularly effusion and tamponade. Therapy should be directed at a specific inciting etiologic agent, if identified. In all patients, anti-inflammatory and symptomatic treatment should aim at alleviating pain, fever, and malaise, using nonsteroidal anti-inflammatory drugs (NSAIDs) as the mainstays. Choice of treatment should be individualized, but indomethacin should be avoided in adults, if possible, because of its deleterious effect on coronary flow. Colchicine added to NSAIDs or as monotherapy is effective both for the initial attack and to prevent recurrences. Corticosteroids should be used only as a last resort (eg, for severe illness resistant to NSAIDs) or to treat specific inciting illnesses.