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Important Safety Information

What is the most important information I should know about NATPARA?

NATPARA may cause serious side effects, including:
Possible bone cancer (osteosarcoma).

  • During animal drug testing, NATPARA caused some rats to develop a bone cancer called osteosarcoma. It is not known if people who take NATPARA will have a higher chance of getting osteosarcoma. Tell your doctor right away if you have pain in any areas of your body that does not go away, or any new or unusual lumps or swelling under your skin that is tender to touch.
  • NATPARA is only available through the NATPARA Risk Evaluation and Mitigation Strategy (REMS) Program. The purpose of the NATPARA REMS Program is to inform patients about the potential risk of osteosarcoma associated with the use of NATPARA. For more information about this REMS program, call 1-855-NATPARA (628-7272) or go to

High blood calcium (hypercalcemia)

  • NATPARA can cause some people to have a higher blood calcium level than normal.
    • Your doctor should check your blood calcium before you start and during your treatment with NATPARA.
    • Tell your doctor if you have nausea, vomiting, constipation, low energy, or muscle weakness. These may be signs that you have too much calcium in your blood.

Low blood calcium (hypocalcemia)

  • People who stop using or miss a dose of NATPARA may have an increased risk of severe low blood calcium levels.
  • Tell your doctor if you have tingling of your lips, tongue, fingers and feet, twitching of face muscles, cramping of feet and hands, seizures, depression, or have problems thinking or remembering.

Tell your doctor right away if you have any of these signs and symptoms of high or low blood calcium levels.

Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

What are the most common side effects of NATPARA?

The most common side effects associated with NATPARA and occurring in more than 10% of patients taking NATPARA were:

  • Paresthesia (tingling, tickling, or burning feeling of the skin), hypocalcemia (low blood calcium), headache, hypercalcemia (high blood calcium), nausea, hypoaesthesia (reduced sense of touch or sensation), diarrhea, vomiting, arthralgia (pain in joints), hypercalciuria (too much calcium in urine), and pain in extremity.

These are not all the possible side effects of NATPARA. For more information, ask your doctor. Call your doctor for medical advice about side effects.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit or call 1-800-FDA-1088. You can also call Shire at 1-866-888-0660.

Please see full Prescribing Information, Medication Guide, and Instructions for Use.

NATPARA® is a registered trademark of Shire-NPS Pharmaceuticals, Inc.

OnePath® is a registered trademark of Shire or its affiliates.

Q-Cliq is a trademark of Shire-NPS Pharmaceuticals, Inc.

SHIRE and the Shire logo are trademarks or registered trademarks of Shire Pharmaceutical Holdings Ireland Limited or its affiliates.