Trastuzumab is a chemotherapy drug that is used to treat breast cancer that has spread to other parts of the body. This medication is injected into a vein once a week by a doctor familiar with chemotherapy drugs. It is often used along with other chemotherapy drugs and may be used to prevent the return of breast cancer or to treat stomach cancer as well as to treat metastasized breast cancer.
This medication can cause serious or life-threatening heart problems. If you have heart disease, you are at greater risk of a heart problem while on this medication. Get emergency medical treatment if you experience shortness of breath, a fast or pounding heartbeat, swelling of the arms, hands, legs or feet, or weight gain of more than 5 pounds within 24 hours.
Some patients may suffer an allergic reaction up to 24 hours after receiving the medication, which can include fever, chills, rash and difficulty breathing.
Don’t take this medication if you are pregnant. It can cause harm to unborn fetuses.