How does targeted therapy work?

Targeted therapy medicines work in various ways. The type of medicine used and its effects depend on the type of cancer being treated. Some medicines help your body attack cancer cells. Others change or slow the growth of cancer cells. Targeted therapy may be used alone or with surgery, chemotherapy, or radiation therapy.

How is targeted therapy given?

Targeted therapy medicine can be given as a pill you take by mouth and swallow. It may be given as an injection. Or it can be given slowly through a small tube (IV) that is placed in a vein in your arm or hand. It may be done at home, or in a healthcare provider’s office, clinic, or hospital. The length of time depends on the type of medicine and how it is given. You may need to have treatments every day, once a week, or every few weeks.

Side effects of targeted therapy

The medicines used to treat cancer also often cause side effects. The side effects vary depending on which medicine is used. Most of the side effects are temporary. They often go away a month or so after treatment ends. The most common side effects are:

• Skin issues. A rash can occur on the head, face, and upper body. The skin may be warm and red. Bumps that look like acne may form on the skin. Your skin may become very dry and crack. It may itch, burn, or hurt when it is touched. It may have a yellow tint to it. Sores may develop on the scalp. The palms of the hands and soles of the feet may become swollen, red, and sore. You may have pain or numbness, redness, swelling, and blisters. Eyelids can become painful, swollen, or itchy. They may flip inward or outward. Cuticles may be red and painful.

• Blood vessel issues. These can include high blood pressure and blood clots. You may also have bleeding, bruising, and poor wound healing. In some people, these issues can cause serious problems that need treatment.

• Digestive issues. These can include nausea, vomiting, diarrhea, or constipation. Digestive issues may also cause dehydration.

Rarely, targeted therapy can cause your hair to become thin and very dry. It may break off more easily. Hair loss may occur on the scalp and lead to bald spots. Or the hair can become curly. Hair may grow in darker during treatment. Hair on the face may grow faster or become thin. Your fingernails and toenails may become weak and break easily, or they may pull away from the skin. These are rare side effects of targeted therapy.

Managing side effects

With targeted therapy, most of the side effects go away after the therapy ends. During treatment, you can help manage side effects. This can help you be more comfortable. Tell your healthcare team as soon as you have side effect symptoms. Talk with them about how to manage your side effects. In some cases, your dose may need to be stopped for a time until your symptoms get better.

Risks and possible complications

Risks and complications of targeted cancer therapy include:

• Infection

• Failure to slow the growth of or kill cancer cells

• Damage to the scalp that causes permanent hair loss

Your healthcare provider will tell you about other risks that may apply to you.