<p>The most serious adverse reactions caused by Trastuzumab includes Cardiomyopathy, Infusion Reactions, Embryo-Fetal Toxicity, Pulmonary Toxicity, Exacerbation of Chemotherapy-Induced Neutropenia. The most common adverse reactions in patients receiving Trastuzumab in the adjuvant and metastatic breast cancer setting are fever, nausea, vomiting, infusion reactions, diarrhea, infections, increased cough, headache, fatigue, dyspnea, rash, neutropenia, anemia, and myalgia.</p>