The most common trastuzumab side effects include back and joint pain, headaches, and loss of appetite. Many patients taking this breast cancer drug also report experiencing headaches, fever, and chills. The side effect of most concern is the possibility that trastuzumab may cause serious and life-threatening heart problems. Severe allergic reactions and lung damage are also associated with this treatment. Patients on this medication are often monitored for signs of these possible side effects.
Trastuzumab, also known as Herceptin, is typically given as an injection when treating a type of breast cancer that has metastasized. The treatment is usually administered in a medical facility. This drug is also used to prevent breast cancer from reoccurring, and in such cases the treatment may last up to 52 weeks depending on how well a patient tolerates the medication.
Typical trastuzumab side effects include muscle, joint, and bone pain. Gastronomic problems like diarrhea, loss of appetite, and heartburn are also common. Some patients reported struggling with insomnia, hot flashes, and excessive tiredness. The arms and legs may tingle, or the patient may develop pale skin or acne. Others experience changes in the appearance of toenails and fingernails.
Treatment with trastuzumab can be complicated by a previous or current heart or lung condition. Congestive heart failure occurs in approximately 7 percent of patients, and other heart problems like tachycardia have been documented. Severe lung damage is another potentially serious side effect of this treatment. Doctors usually monitor patients closely during treatment for signs of these possible trastuzumab side effects, and patients should be forthcoming about heart and lung conditions.
A trastuzumab injection can also cause a potentially fatal allergic reaction. The reaction can begin as soon as the medication is administered or up to 24 hours later. Symptoms of such a reaction can include fever, nausea, and vomiting. Difficulty breathing, headaches, and dizziness may also be cause for concern. A doctor will often watch the patient closely while this medication is administered so that the process can be stopped at the first sign of a severe reaction.
This drug is an antibody that interferes with the HER2 receptor. HER receptors regulate cellular functions that are weakened or amplified in cancer cells. In cases of breast cancer, the HER2 receptor causes uncontrolled reproduction of breast cells. When the antibody in trastuzumab binds to the HER2 protein, the protein can no longer affect breast cell reproduction. As a result, survival rates increase, although there is the possibility that the cancer will become resistant to this drug.
Despite studies that have demonstrated trastuzumab’s effectiveness in cases of metastatic breast cancer, the drug remains controversial. There is some debate regarding its effectiveness in earlier stages of the disease. Additionally, treatment can be prohibitively expensive, and some insurance companies have balked at paying for it.
Like any drug, trastuzumab can react to other medications and vitamins, supplements, and herbal remedies. Not all trastuzumab side effects may be reported and fully documented. Patients taking this drug should consult and update their medical care providers. Additional side effects can usually be reported directly to the government. For example, in the United States, patients can report side effects to the Food and Drug Administration online or by calling a toll-free number.