Chemotherapy for breast cancer doesn’t always have to be through an IV. Some drugs are available in pill form. Other oral medications that are part of breast cancer treatment include antihormone and targeted therapy pills.

People commonly associate chemotherapy with intravenous (IV) cancer drugs in a hospital or doctor’s office. This has been the traditional nonsurgical method of treating cancer.

Recent advances in cancer treatments have made chemotherapy pills an option for many types of cancer. A few are approved for breast cancer.

Not all traditional chemotherapy drugs come in an oral form.

It’s important to know the difference between the various forms of oral medication prescribed to treat breast cancer, Dr. Hannah Luu, a California-based oncologist and the CEO and founder of OncoGambit, an online service that creates personalized cancer treatment plans, told Healthline.

She outlines three categories of oral medications people with cancer may take as part of their treatment plan:

  • chemotherapy pills
  • antihormone pills
  • targeted therapy (precision medicine) pills

Each therapy works differently and serves a different purpose, and not every medication will be right for everyone. Which therapy is right for you will depend on many factors, including the type and stage of cancer you have and other health considerations.

A few chemotherapy medications commonly prescribed to treat cancer are available as pills.

Capecitabine (Xeloda)

Capecitabine (Xeloda) is a type of oral chemotherapy often prescribed to treat metastatic breast cancer.

It’s sometimes used alongside targeted therapy, or on its own if the cancer has stopped responding to other types of therapy. In some cases, it may also be used after radiation therapy.

When you take capecitabine, it’s still in its inactive form. Certain enzymes found in cancer cells activate the medication and convert it to a compound called 5-fluorouracil, which can kill cancer cells by preventing them from dividing.

Like other types of chemotherapy, capecitabine is associated with several possible side effects, including:

If you’re taking any blood thinners like warfarin, your doctor may need to monitor and adjust your dosage regularly, as capecitabine could interfere with these medications.

Capecitabine may not be suitable for everyone, including people who are pregnant and those with severe kidney or liver conditions.

Cyclophosphamide (Cytoxan)

Cyclophosphamide (Cytoxan) is another type of oral chemotherapy that’s included in a combined treatment regimen called CMF (cyclophosphamide, methotrexate, fluorouracil). However, cyclophosphamide is commonly used in an IV form, similar to methotrexate and 5-fluorouracil.

Cyclophosphamide can help treat breast cancer by blocking the growth of cancer cells in your body.

Some of the possible side effects of Cytoxan include:

  • nausea
  • vomiting
  • diarrhea
  • hair loss
  • loss of appetite
  • unintentional weight loss
  • sores in the mouth or tongue
  • changes in skin color

Cytoxan is not recommended for people with health conditions that block the flow of urine, as it could cause serious side effects. People who are pregnant or breastfeeding should also not use Cytoxan.

Methotrexate

Methotrexate is a commonly used chemotherapy treatment for cancer and other conditions. Because of its cytotoxic effect, it’s used in the treatment of cancer. “Cytotoxic” means toxic to cells.

Although it’s often administered through an IV, methotrexate is also available in pill form.

Common side effects include:

  • nausea
  • vomiting
  • mucosal ulcers
  • loss of appetite

It’s often used in a chemotherapy treatment regimen involving cyclophosphamide and fluorouracil.

Your doctor may prescribe several treatments known as targeted therapies in an oral form. Here is how they differ from traditional chemo:

Chemotherapy

Chemotherapy is a type of cancer treatment that works by killing fast-growing cells in your body to help prevent the growth and spread of cancer cells. It can be given as an oral medication or administered through an IV.

Because chemotherapy can kill both healthy and cancerous cells in your body, it can cause many side effects.

Targeted therapy

Targeted therapy attacks cancer cells specifically by interfering with certain pathways that control their growth. It also prevents cancer cells from multiplying and spreading.

Unlike chemotherapy, targeted therapy is designed to only affect cancer cells, meaning it’s less likely to harm the healthy cells in your body. But targeted therapy pills can cause a range of side effects, from diarrhea to high blood pressure.

Targeted therapy can be administered orally or through an IV to treat breast cancer. It’s often used alone or with other cancer treatments, including chemotherapy.

How does targeted therapy work?

Each type of targeted therapy works a little differently, but all tend to interfere with the ability of cancer cells to:

  • grow
  • divide
  • repair
  • communicate with other cells

What are the types of targeted therapies?

There are several types of targeted therapies available for the treatment of breast cancer:

  • Monoclonal antibodies: These medications are often combined with toxins, chemotherapy drugs, and radiation. They attach to targets on the surface of cancer cells to deliver these substances, causing cancer cells to die without harming healthy cells.
  • Small-molecule inhibitors: These drugs generally target and inhibit specific pathways and processes that cause cancer cells to proliferate. They must be small enough to enter the cell and interfere with proteins on both the inside and outside of the cell.
  • Angiogenesis inhibitors: These drugs inhibit the formation of new blood vessels, which fuel the growth of cancer cells.

Trastuzumab (Herceptin) and pertuzumab (Perjeta) are the two most common monoclonal antibodies used to treat human epidermal growth factor receptor 2 (HER2) positive breast cancer. These medications are typically administered through an IV infusion and are used with chemotherapy.

Neratinib (Nerlynx) is another type of oral targeted therapy. It’s designed to help prevent the recurrence of HER2-positive breast cancer for people who have completed 1 year of Herceptin.

Other drugs, like lapatinib (Tykerb) and tucatinib (Tukysa), both oral medications, and ado-trastuzumab emtansine (Kadcyla), which is administered through an IV, are also available for the treatment of advanced HER2-positive breast cancer.

Capecitabine (Xeloda) and cyclophosphamide (Cytoxan) are chemotherapy drugs available in pill form for the treatment of breast cancer.

Targeted therapies may also be an option. Targeted therapies are different from chemotherapy because they don’t target healthy cells, only specific parts of cancer cells.

Talk with your healthcare team to determine the best solution for you.