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Generic Name: tucatinib (tablets)

Medically reviewed by Judith Stewart, BPharm Last updated on Apr 18, 2020.

What is Tukysa?

Tukysa is a prescription medicine used with the medicines trastuzumab and capecitabine to treat adults with:

  • human epidermal growth factor receptor-2 (HER2) positive breast cancer that has spread to other parts of the body such as the brain (metastatic), or that cannot be removed by surgery, and
  • who have received one or more anti-HER2 breast cancer treatments.
  • Important information: Tukysa is used with the medicines trastuzumab and capecitabine, also read the Medication Guide that comes with capecitabine.

It is not known if this medicine is safe and effective in children.

Before taking Tukysa

Before taking Tukysa, tell your healthcare provider about all of your medical conditions, including if you:

  • have liver problems.
  • are pregnant or plan to become pregnant. Tukysa can harm your unborn baby.
    Females who are able to become pregnant:
    • Your healthcare provider will do a pregnancy test before you start treatment.
    • You should use effective birth control (contraception) during treatment, and for at least 1 week after the last dose. Talk with your healthcare provider about forms of birth control that you can use during this time.
    • Tell your healthcare provider right away if you become pregnant or think you may be pregnant during treatment.
    Males with female partner who are able to become pregnant should use effective birth control during treatment, and for at least 1 week after the last dose.
  • are breastfeeding or plan to breastfeed. It is not known if Tukysa passes into your breast milk. Do not breastfeed during treatment, and for at least 1 week after the last dose.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Tukysa may affect the way your other medicines work, and other medicines may affect the way Tukysa works.

Know the medicines you take. Keep a list of all the medicines you take and show it to your healthcare provider and pharmacist every time you get a new medicine.

How should I take Tukysa?

  • Take Tukysa exactly as your healthcare provider tells you.
  • Tukysa is used with the medicines trastuzumab and capecitabine. Your healthcare provider will tell you the dose of trastuzumab and capecitabine you will take and how you will receive them.
  • Take Tukysa 2 times a day, with or without a meal.
  • Take Tukysa tablets about 12 hours apart or at the same times every day.
  • Swallow the tablets whole. Do not chew, crush, or split the tablets before swallowing. Do not take the tablets if they are broken, cracked, or damaged.
  • If you vomit or miss a dose, take your next dose at your regular time.

Tukysa side effects

Tukysa may cause serious side effects, including:

  • Diarrhea. Diarrhea is common with Tukysa and can sometimes be severe. Tell your healthcare provider if you have a change in your bowel movements or severe diarrhea. Severe diarrhea can lead to loss of too much body fluids (dehydration), low blood pressure, kidney problems and death. Your healthcare provider may prescribe medicines to treat your diarrhea during treatment with Tukysa.
  • Liver Problems. Tukysa can cause severe liver problems. Your healthcare provider will do blood tests to check your liver function before and every 3 weeks during treatment, or as needed. Tell your healthcare provider right away if you have any signs and symptoms of liver problems including:
    • itching
    • yellowing of your skin or eyes
    • dark or brown urine (tea-colored)
    • pain in the upper right side of your stomach-area (abdomen)
    • feel very tired
    • decreased appetite
    • bleeding or bruising more easily than normal

The most common side effects of Tukysa:

  • diarrhea
  • rash, redness, pain, swelling or blisters on the palms of your hands or soles of your feet
  • mouth sores (stomatitis)
  • decreased appetite
  • stomach-area (abdomen) pain
  • nausea
  • tiredness
  • increased liver function blood tests
  • vomiting
  • headache
  • low red blood cell counts (anemia)
  • rash

Your healthcare provider may change your dose, temporarily stop, or permanently stop treatment with Tukysa if you have certain side effects.

Tukysa may cause fertility problems in males and females, which may affect the ability to have children. Talk to your healthcare provider if you have concerns about fertility.

These are not all of the possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store Tukysa?

  • Store Tukysa at room temperature 68°F to 77°F (20ºC to 25ºC).
  • Keep Tukysa in its original container. The bottle contains a desiccant packet to help keep your tablets dry (protect from moisture). Keep the desiccant in the bottle.
  • Tightly close the bottle after you take your dose.
  • Tukysa must be used within 3 months after opening the bottle. Throw away (discard) any unused tablets 3 months after opening the bottle.

Keep all medicines out of reach of children and pets.

General information about the safe and effective use of Tukysa.

Medicines are sometimes prescribed for conditions not listed in the Patient Information. Do not use this medicine for a condition for which it was not prescribed. Do not give it to other people, even if they have the same symptoms that you have. It may harm them. You can ask your pharmacist or healthcare provider for information that is written for healthcare professionals.

What are the ingredients in Tukysa?

Active ingredient: tucatinib

Inactive ingredients:
Tablet core: copovidone, crospovidone, sodium chloride, potassium chloride, sodium bicarbonate, colloidal silicon dioxide, magnesium stearate, and microcrystalline cellulose.
Tablet coating: yellow film coat: polyvinyl alcohol, titanium dioxide, macrogol/polyethylene glycol, talc, and yellow iron oxide non-irradiated.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

More about Tukysa (tucatinib)

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