Drug-induced edema has been described for a number of medications. Mechanisms: Enhanced sodium and water reabsorption by kidneys; potent vasodilators and calcium channel blockers (cause capillary leakage); non-steroidal anti-inflammatory drugs (NSAIDs) inhibit renal prostaglandin synthesis. Other drug products associated with peripheral edema: Antidepressants, estrogens, corticosteroids, COX-2 inhibitors. Edema definition: presence of abnormally large amounts of fluid in intercellular tissue spaces. Usually refers to demonstrable amounts of fluid in subcutaneous tissues. May be localized (due to venous or lymphatic obstruction or increased vascular permeability) or systemic (due to heart failure or renal disease). Sometimes designated by other terms according to site (ascites, hydrothorax, or hydropericardium). Massive generalized edema is called anasarca. Synonyms: dropsy and hydrops. Effusion definition: escape of fluid from lymphatics or blood vessels into a cavity or tissues; results from altered hydrostatic forces