The cause of pericarditis must be identified, if possible.

In most types of pericarditis, it is necessary to treat the pain with analgesics (pain killers). The inflammation of the pericardium is treated with anti-inflammatory drugs(NSAIDS) such as aspirin and ibuprofen; in some cases, corticosteroids may be prescribed.

Diuretics may be used to remove excess fluid accumulated in the pericardial sac. If the buildup of pericardial fluid makes the heart function poorly or produces cardiac tamponade, it is necessary to drain the fluid through pericardiocentesis (removal of excess fluid from the pericardial sac). Pericardiocentesis may be either percutaneous (using a needle to reach the pericardium, guided with echocardiography, in the procedure room), or surgical (done in the operating room as a minor surgery).

Bacterial pericarditis should be treated with antibiotics. Fungal pericarditis should be treated with antifungal agents.

If the pericarditis is chronic, recurrent, or results in constrictive pericarditis, it may be advisable to perform pericardiectomy (cutting or removal of part of the pericardium).

• Arrhythmias, such as atrial fibrillation. When pericarditis accompanies myocarditis, other arrhythmias may be present, such as supraventricular tachycardia (SVT) or complete heart block.
• Cardiac tamponade
• Constrictive pericarditis, where inflammation of the pericardial sac results in fibrosis and thickening of the pericardium with adhesions (i.e., sticky scars) between the pericardium and the heart. The pericardium creates a rigid "case" around the heart and can severly limit the ability of the heart to fill with blood during diastole (i.e., the relaxation phase before the next heartbeat). Patients with constrictive pericarditis may develop heart failure which responds poorly to treatment. Constrictive pericarditis needs to be differentiated from a chronic heart condition called restrictive cardiomyopathy, which produces symptoms and signs similar to constrictive pericarditis.