Health Library

Asfotase alfa (By injection)

Asfotase Alfa (AS-foe-tase AL-fa)

Treats perinatal, infantile, and juvenile-onset hypophosphatasia (HPP).

Brand Name(s):

Strensiq

When This Medicine Should Not Be Used:

How to Use This Medicine:

Injectable

• Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot under your skin. It is usually given in the upper arm, buttock, stomach, or thigh. Do not inject this medicine into the buttocks for infants.
• A nurse or other health provider will give you this medicine.
• You may be taught how to give your medicine at home. Make sure you understand all instructions before giving yourself an injection. Do not use more medicine or use it more often than your doctor tells you to. Use 2 separate injection sites when giving 2 doses of this medicine.
• You will be shown the body areas where this shot can be given. Use a different body area each time you give yourself a shot. Keep track of where you give each shot to make sure you rotate body areas.
• Do not inject into skin areas that are red, hot, or swollen.
• Use a new needle and syringe each time you inject your medicine.
• Allow this medicine to warm to room temperature for at least 15 to 30 minutes before you use it. Do not warm it using heat sources (including microwave or hot water).
• Check the liquid in the vial. It should be clear or slightly yellow and may have a few small white particles in it. Do not use the medicine if the liquid is discolored or has lumps or large particles in it. Do not shake the vial.
• Use the vial only once. Do not save leftover medicine.
• Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
• Missed dose: Call your doctor or pharmacist for instructions.
• If you store this medicine at home, keep it in the refrigerator. Do not freeze. Use the vial within 3 hours after removing it from the refrigerator.
• Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease or eye or vision problems.
• This medicine may cause the following problems:
  • Redistribution of body fat
  • Calcium deposits in the eyes and kidneys, which can lead to serious eye or vision problems or kidney problems
• Call your doctor if your symptoms do not improve or if they get worse.
• Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
• Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Difficult or painful urination, bloody urine, nausea, vomiting, pain in the groin or genitals, sharp back pain just below the ribs
• Increased difficulty with breathing or walking, new broken bones (fractures)
• Redness or dryness of the eye, seeing floating dark spots or material before the eyes
• Thickening, depression, or indentation of the skin at the injection site
• Weight gain around your neck, upper back, breast, face, or waist

If you notice these less serious side effects, talk with your doctor:

• Pain, itching, redness, or swelling where the shot was given

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024