Hunter syndrome

What is Hunter syndrome?

Hunter syndrome, or mucopolysaccharidosis II (MPS II), is an inherited genetic disease. It mostly affects males. It is caused by a mutation in a certain gene. This affects the body’s ability to make an enzyme called iduronate-2-sulfatase (I2S). When I2S isn’t working as it should, the body can’t break down and recycle a type of sugar called glycosaminoglycans, or GAGs. As a result, GAGs build up in the body’s cells.

Hunter symptoms

Hunter syndrome is a progressive disease with a wide range of symptoms. They span from mild to severe and can include:


  • Runny nose
  • Colds
  • Enlarged tongue and tonsils
  • Chronic ear infections
  • Coarse facial features

Behavioral problems

  • Tantrums
  • Obstinacy (stubbornness)
  • Aggressiveness
  • Hyperactivity


  • Hernia
  • Chronic diarrhea
  • Enlarged liver and spleen


  • Stiffness
  • Pain

Generally, newborn babies don’t have Hunter syndrome symptoms. Signs become visible in children around ages 2 to 4.

Hear from people living with Hunter syndrome

Discover inspiring real-life stories from others living with or caring for someone with Hunter syndrome. Their journeys of self-discovery, full of purpose and grit, are sure to move you.

Finding support* from Takeda offers information for people living with Hunter syndrome and those who care for them. There are links to websites and informative videos, and downloadable tools. You’ll also find inspiring family stories and much more.

The National MPS Society provides hope and support for individuals and families affected by MPS through research, advocacy, and awareness. Browse MPS resources, apply for family support programs, or get involved in fundraising.

National Organization for Rare Disorders (NORD) is a rare disease umbrella organization that provides advocacy, research, education, and patient services in the US. See how they help and find out how you can get involved.

*The above links are provided as a resource. This is not an endorsement, and Takeda has no control over the content of any website not owned by Takeda.

Get health education support from OnePath

OnePath offers health education support from a Healthcare Educator (HCE). HCEs are trained nursing professionals. They can help answer your questions about Hunter syndrome and your prescribed Takeda treatment.

Find OnePath tools to help you during treatment

Track how you or your loved one is feeling with our convenient Health Events Log in the OnePath App or Portal.

Frequently asked questions

Call your OnePath Patient Support Manager (PSM) if you feel you need more training on taking your treatment. To connect with your PSM, call Monday through Friday, 8:30 AM to 8:00 PM ET, at 1-866-888-0660.

OnePath specialists are here to help answer questions about your condition and your Takeda treatment plan. Your Patient Support Manager (PSM) can connect you with one of these specialists. Call us Monday through Friday, 8:30 AM to 8:00 PM ET, at 1-866-888-0660. You should also speak with your healthcare provider if you have specific questions about your health.

If you’ll be traveling with your Takeda medication, your dedicated Patient Support Manager (PSM) can help you prepare. Call your PSM as early as possible, at least 2-3 weeks before your trip. Your PSM can:

  • Put you in touch with your specialty pharmacy to discuss your travel plans. Your SP can:
    • Work with you to have extra medication shipped to you before you travel
    • Have your medication shipped to your destination
    • Help locate a site of care if your treatment must be given to you by a trained healthcare provider

Below you’ll find more tips you may want to consider when planning to travel with your medication:

  • Tell your healthcare provider about your plans. Follow any instructions they may provide you
  • Make a list of hospitals along your travel route and near your destination. Be sure to include their contact information
  • Always keep your treatment and supplies with you (if applicable). This includes storing these items in your carry-on luggage. That way, you’ll be able to use your items at any time on the way to your destination. Also, they’ll be better protected against temperature changes, rough handling, or loss
  • Pack extra medication just in case you experience a travel delay
  • If you’ll be flying, call your airline before the trip. Ask if it would be possible to keep your medication refrigerated during your flight, if applicable
  • Call the Transportation Security Administration (TSA) at least 72 hours before traveling. It can let you know what to expect at security checkpoints and if there are any special instructions you’ll need to follow. You can call the TSA toll-free at 1-866-289-9673 or visit them online here
  • When going through security, carry a copy of a travel letter describing your condition and the need for your medication
  • Always wear a medical ID bracelet or carry a medical ID card with you
  • Make sure to have all medication, supplies, and medical devices clearly labeled

If you have questions, speak with your Patient Support Manager (PSM). To connect with your PSM, call us Monday through Friday, 8:30 AM to 8:00 PM ET, at 1-866-888-0660.