What is CRYSVITA?
CRYSVITA is a prescription medicine used to treat adults and children 6 months of age and older with X-linked hypophosphatemia (XLH).
Patient and caregiver resources for CRYSVITA and XLH
Explore the following resources to learn more about CRYSVITA and how it can
help you manage your or your child’s XLH.
Brochure for adults with XLH
This helpful brochure is for adults with XLH who want to learn more about how CRYSVITA helps treat XLH.
Download (PDF)
Brochure for caregivers of children with XLH
This helpful brochure is for caregivers of children with XLH who want to learn
more about how CRYSVITA helps treat XLH.
CRYSVITA Doctor Discussion Guide for
adults
Use this doctor discussion guide to help you prepare for your visit. That way, you can have a better conversation about whether CRYSVITA is right for you.
Download (PDF)
CRYSVITA Doctor Discussion Guide for caregivers
Use this doctor discussion guide to help you prepare for your child’s visit. That
way, you can have a better conversation about whether CRYSVITA is right for
your child.
XLH guidelines and your child
Learn how CRYSVITA is included in
expert guidelines for treating XLH in
children. You can share this information with your child’s doctor at their next appointment.
XLH guidelines and you
Learn how CRYSVITA is included in
expert guidelines for treating XLH in
adults. You can share this information
with your doctor at your next
appointment.
REAL XLH STORIES
Staying connected
“There’s nothing like talking to people who personally understand what you’ve been through instead of just seeing it written in a doctor’s note.”
Read Robert’s full story
XLH community groups and networks
Connect with others in the XLH community. Even though XLH may be rare, you’re not alone. The groups listed below provide support and education for people living with XLH.
The XLH Network
The XLH Network, a 501(c)(3) nonprofit organization, seeks to connect people around the world who are affected by or interested in learning more about XLH.
The XLH Network connects affected individuals, families, and medical professionals.
National Organization for Rare Disorders (NORD)
NORD is a patient advocacy organization dedicated to individuals with rare
diseases and the organizations that
serve them.
Global Genes
Global Genes is a rare disease patient advocacy organization that works to
build awareness, educate the global community, and provide connections and resources.
Got Transition
Got Transition is the national resource center for healthcare transition. Its aim is to improve the transition from pediatric to adult health care through the use of evidence-driven strategies for healthcare professionals, youth, young adults, and their caregivers.
Visit GOT TRANSITION
NIH Genetic and Rare
Diseases Information
Center (GARD)
GARD maintains a list of rare diseases
and related terms to help people find reliable information.
This is a selected list and does not include every organization, service, or online resource available. The links provided lead to third-party websites that are not operated, reviewed, or endorsed by Kyowa Kirin.
Need help finding a doctor who manages XLH?
Indication
What is CRYSVITA?
CRYSVITA is a prescription medicine used to treat adults and children 6 months of age and older with X-linked hypophosphatemia (XLH).
Important Safety Information
You should not take CRYSVITA if:
- You take an oral phosphate supplement and/or a specific form of vitamin D supplement (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
- Your phosphorus levels from a blood sample are within or above the normal range for age.
- You have kidney problems.
What is the most important information you should know about CRYSVITA?
- Some patients developed allergic reactions (e.g., rash and hives) while taking CRYSVITA. Your doctor will monitor you for symptoms of an allergic reaction while you are taking CRYSVITA. Your treatment may need to be discontinued for serious allergic reactions.
- High levels of phosphorus in the blood have been reported in some patients taking CRYSVITA. This may be related to a risk of high calcium levels in the kidneys. Your doctor will collect blood samples to monitor your levels. If you are already taking CRYSVITA, dose interruption and/or dose reduction may be required based on your serum phosphorus levels.
- High levels of calcium in the blood have been reported in patients taking CRYSVITA. The risk is greater in patients with pre-existing hyperparathyroidism (overactive parathyroid glands), for those who are unable to move for extended periods of time, become dehydrated, have high vitamin D levels, or have kidney issues. If you are at greater risk, your doctor will monitor your blood calcium and parathyroid hormone levels before you start and while taking CRYSVITA. If you develop high levels of blood calcium, your doctor may need to stop your treatment until it is adequately managed.
- Administration of CRYSVITA may result in reactions at the injection site, such as hives, reddening of the skin, rash, swelling, bruising, pain, severe itching of the skin, and collection of blood outside of a blood vessel (i.e., hematoma). Call your doctor if you develop an injection site reaction. CRYSVITA may be discontinued if severe injection site reactions occur.
What are the possible side effects of CRYSVITA?
- Adverse reactions that were seen in children with XLH are:
- Fever
- Injection site reaction
- Cough
- Vomiting
- Pain in arms and legs
- Headache
- Tooth abscess
- Dental cavities
- Diarrhea
- Decreased vitamin D levels
- Toothache
- Constipation
- Muscle pain
- Rash
- Dizziness
- Nausea
- Adverse reactions that were seen in adults with XLH are:
- Back pain
- Headache
- Tooth infection
- Restless legs syndrome
- Decreased vitamin D levels
- Dizziness
- Constipation
- Muscle spasms
- Phosphorus levels increased in the blood
- Narrowing of the spaces within the spine is common in adults with XLH, and pressure on the spinal cord has been reported in adults taking CRYSVITA. It is not known if taking CRYSVITA worsens the narrowing of the spaces within the spine or the pressure on the spinal cord.
Before taking CRYSVITA, tell your doctor about all of your medications (including supplements) and medical conditions, including if you:
- Are taking oral phosphate and/or active vitamin D (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
- Are pregnant, think you may be pregnant, or plan to become pregnant. There is not enough experience to know if CRYSVITA may harm your unborn baby. Report pregnancies to the Kyowa Kirin, Inc. Adverse Event reporting line at 1-844-768-3544.
- Are breastfeeding or plan to breastfeed. There is not enough experience to know if CRYSVITA passes into your breast milk. Talk with your doctor about the best way to feed your baby while you receive CRYSVITA.
While taking CRYSVITA, tell your doctor if you experience:
- An allergic reaction such as rash or hives
- A rash, swelling, bruising, or other reaction at the injection site
- New or worsening restless legs syndrome
These are not all the possible side effects of CRYSVITA. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Kyowa Kirin, Inc. at 1-844-768-3544.
For important risk and use information, please see the full Prescribing Information for CRYSVITA.
What is CRYSVITA?
CRYSVITA is a prescription medicine used to treat adults and children 6 months of age and older with X-linked hypophosphatemia (XLH).
Important Safety Information
You should not take CRYSVITA if:
- You take an oral phosphate supplement and/or a specific form of vitamin D supplement (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
- Your phosphorus levels from a blood sample are within or above the normal range for age.
- You have kidney problems.
What is the most important information you should know about CRYSVITA?
- Some patients developed allergic reactions (e.g., rash and hives) while taking CRYSVITA. Your doctor will monitor you for symptoms of an allergic reaction while you are taking CRYSVITA. Your treatment may need to be discontinued for serious allergic reactions.
- High levels of phosphorus in the blood have been reported in some patients taking CRYSVITA. This may be related to a risk of high calcium levels in the kidneys. Your doctor will collect blood samples to monitor your levels. If you are already taking CRYSVITA, dose interruption and/or dose reduction may be required based on your serum phosphorus levels.
- High levels of calcium in the blood have been reported in patients taking CRYSVITA. The risk is greater in patients with pre-existing hyperparathyroidism (overactive parathyroid glands), for those who are unable to move for extended periods of time, become dehydrated, have high vitamin D levels, or have kidney issues. If you are at greater risk, your doctor will monitor your blood calcium and parathyroid hormone levels before you start and while taking CRYSVITA. If you develop high levels of blood calcium, your doctor may need to stop your treatment until it is adequately managed.
- Administration of CRYSVITA may result in reactions at the injection site, such as hives, reddening of the skin, rash, swelling, bruising, pain, severe itching of the skin, and collection of blood outside of a blood vessel (i.e., hematoma). Call your doctor if you develop an injection site reaction. CRYSVITA may be discontinued if severe injection site reactions occur.
What are the possible side effects of CRYSVITA?
- Adverse reactions that were seen in children with XLH are:
- Fever
- Injection site reaction
- Cough
- Vomiting
- Pain in arms and legs
- Headache
- Tooth abscess
- Dental cavities
- Diarrhea
- Decreased vitamin D levels
- Toothache
- Constipation
- Muscle pain
- Rash
- Dizziness
- Nausea
- Adverse reactions that were seen in adults with XLH are:
- Back pain
- Headache
- Tooth infection
- Restless legs syndrome
- Decreased vitamin D levels
- Dizziness
- Constipation
- Muscle spasms
- Phosphorus levels increased in the blood
- Narrowing of the spaces within the spine is common in adults with XLH, and pressure on the spinal cord has been reported in adults taking CRYSVITA. It is not known if taking CRYSVITA worsens the narrowing of the spaces within the spine or the pressure on the spinal cord.
Before taking CRYSVITA, tell your doctor about all of your medications (including supplements) and medical conditions, including if you:
- Are taking oral phosphate and/or active vitamin D (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
- Are pregnant, think you may be pregnant, or plan to become pregnant. There is not enough experience to know if CRYSVITA may harm your unborn baby. Report pregnancies to the Kyowa Kirin, Inc. Adverse Event reporting line at 1-844-768-3544.
- Are breastfeeding or plan to breastfeed. There is not enough experience to know if CRYSVITA passes into your breast milk. Talk with your doctor about the best way to feed your baby while you receive CRYSVITA.
While taking CRYSVITA, tell your doctor if you experience:
- An allergic reaction such as rash or hives
- A rash, swelling, bruising, or other reaction at the injection site
- New or worsening restless legs syndrome
These are not all the possible side effects of CRYSVITA. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Kyowa Kirin, Inc. at 1-844-768-3544.
For important risk and use information, please see the full Prescribing Information for CRYSVITA.
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COMM-US-CRY-0930 June 2026