感染性心內膜炎是種可能致命的疾病。在投予抗生素之前應該常規進行血液培養，以確認可能造成感染性心內膜炎的微生物菌種，繼而引導抗菌藥物治療的方向。在決定感染性心內膜炎治療週期前必須確認微生物已經完全被殺死，尤其是位於贅生物 (vegetation) 中的微生物。有時候延長治療週期是必要的，因為在贅生物中的細菌密度很高，且贅生物中沒有血液流動無法將藥物送入其中，所以難以達到有效的治療濃度。另外有些抗生素的殺菌活性是較為緩慢的，例如：β-lactams 類抗生素及vancomycin。唯有當抗生素的殺菌活性可以更快速或贅生物中的細菌負荷量可能較少的情況下，較短周期的抗生素療程才可被採用。Aminoglycosides 與細胞膜抑制劑（例如：beta-lactams 及glycopeptides）合併投與時，有助於根除可能造成感染性心內膜炎的致病微生物。假如療程結束後血液培養仍呈現陽性反應就應該開始新療程的藥物治療，而抗生素的選擇則由所分離出來的菌株敏感性決定。
 

treatment for infective endocarditis must ensure complete eradication of microorganisms, especially those within vegetations. Prolonged therapy may be required as bacterial densities within vegetations are high and some antibiotics show relatively slow bactericidal activity, such as β-lactams and vancomycin. A shorter duration of antimicrobial therapy is available, but only when more rapid bactericidal activity is known or lower vegetation bacterial burden is likely. Concurrent use of aminoglycosides and cell-wall inhibitors (e.g., Beta-lactams and glycopeptides) are helpful to eradicate possible organisms of infective endocarditis. However, a new course of pharmacotherapy should start if blood cultures are positive, and the choice of antibiotics was based on the susceptibility of the bacterial isolates.