Anthracycline (doxorubicin) and trastuzumab treatments for cancer patients have been known to cause cardiotoxicity. The current recommendations for prevention of cardiac events from cancer chemotherapies are largely based on opinion. The American Society of Clinical Oncology recommends active screening and prevention of modifiable cardiovascular risk factors. The risk factors are defined as tobacco use, high blood pressure, high cholesterol, alcohol use, obesity, and physical inactivity. Beta-adrenergic blockers and angiotensin converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs) have been the mainstay of treatment for heart failure patients with reduced left ventricular ejection fraction for many years. This review analyzed the use of beta-adrenergic blockers and ACE inhibitors/ARBs as protection against cardiomyopathy caused by anthracyclines and trastuzumab. Although many more studies are warranted, it was concluded that the addition of a beta-blocker early in the treatment of cancer patients who are undergoing anthracycline or trastuzumab treatment can have beneficial effects in preserving left ventricular ejection fraction and preventing chemotherapy-induced cardiotoxicity. The effects are more apparent in the short term. More studies of the long-term effects are warranted, as are the additive effects of using a beta-blocker and ACE inhibitor/ARB together to prevent chemotherapy-induced cardiotoxicity.