It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and to check for any unwanted effects.
Your doctor may test your heart before you start receiving trastuzumab and while you are getting treatments with this medicine. Contact your doctor right away if you experience any chest pain, increased coughing, trouble with breathing, a sudden difficulty with breathing at night, rapid weight gain, or abnormal swelling in your ankles or legs. These could be symptoms of serious heart problems.
Using this medicine while you are pregnant may cause very serious birth defects (e.g., decreased amniotic fluid, bone problems). Use an effective form of birth control to keep from getting pregnant during treatment and for 6 months after the last dose of this medicine. If you think you have become pregnant while using the medicine, tell your doctor right away. Your doctor may want you to join a pregnancy registry for patients receiving this medicine.
Trastuzumab may cause a serious side effect called an infusion reaction. This can be life-threatening and requires immediate medical attention. Tell your doctor or nurse right away if you have a fever, chills, chest pain, lightheadedness, dizziness, fainting, headache, rash, pain, nausea, vomiting, trouble with breathing, or weakness within a few hours after you receive it.
This medicine can temporarily lower the number of white blood cells in your blood, which increases the chance of getting an infection. If this occurs, there are certain precautions you can take to reduce the risk of infection:
- If you can, avoid people with infections. Check with your doctor right away if you think you are getting an infection or if you get a fever or chills, a cough or hoarseness, lower back or side pain, or have painful or difficult urination.
- Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
Tell your doctor right away if you are having shortness of breath, chest tightness, or any type of breathing problem while receiving this medicine.
Cancer medicines can cause nausea or vomiting in most people, sometimes even after receiving medicines to prevent it. Ask your doctor or nurse about other ways to control these side effects.