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Generic Name: asfotase alfa (AS foe tase AL fa)
Brand Name: Strensiq

What is asfotase alfa?

Asfotase alfa is an enzyme replacement medicine that is used to treat hypophosphatasia (HYE-poe-FOS-fa-TAY-zha).

Hypophosphatasia is a rare genetic disorder in which there is a deficiency of an enzyme that helps the body process calcium and phosphorus. This leads to abnormal growth and development of the bones and teeth, including soft or brittle bones, growth problems, and tooth loss.

Asfotase alfa may also be used for purposes not listed in this medication guide.

What is the most important information I should know about asfotase alfa?

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

What should I discuss with my healthcare provider before using asfotase alfa?

You should not use asfotase alfa if you are allergic to it.

Before you use asfotase alfa, tell your doctor about all your medical conditions or allergies.

Your name may be listed on a patient registry while you are using asfotase alfa. This is to track and evaluate any long-term effects of using this medicine.

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether asfotase alfa passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How should I use asfotase alfa?

Asfotase alfa is usually given 3 to 6 times per week. Follow all directions on your prescription label. Do not use this medicine in larger or smaller amounts or for longer than recommended.

Asfotase alfa is injected under the skin. You may be shown how to use injections at home. Do not give yourself this medicine if you do not understand how to use the injection and properly dispose of used needles and syringes.

Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.

You may need to use 2 vials and 2 separate syringes to make up a single dose of this medicine. Follow your doctor's dosing instructions very carefully.

Your care provider will show you the best places on your body to inject asfotase alfa. Use a different place each time you give an injection. Do not inject into the same place two times in a row.

Do not use asfotase alfa if it has changed colors or has particles in it. Call your pharmacist for new medication.

Each single-use vial (bottle) of this medicine is for one use only. Throw away after one use, even if there is still some medicine left in it after injecting your dose.

Use a disposable needle and syringe only once. Follow any state or local laws about throwing away used needles and syringes. Use a puncture-proof "sharps" disposal container (ask your pharmacist where to get one and how to throw it away). Keep this container out of the reach of children and pets.

While using asfotase alfa, you may need frequent eye examinations.

Tell your doctor if you have any changes in weight. Asfotase alfa doses are based on weight (especially in children), and any changes may affect the dose.

Store vials in the original container in a refrigerator, protected from light. Do not freeze or shake this medicine.

You may take the medicine out of the refrigerator and allow it to reach room temperature before preparing a dose. Do not leave the medicine at room temperature for longer than 1 hour.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose of asfotase alfa.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using asfotase alfa?

Do not inject this medicine into skin areas that are red or swollen.

Asfotase alfa side effects

Get emergency medical help if you have signs of an allergic reaction: hives; dizziness, nausea, vomiting; difficult breathing; swelling of your face, lips, tongue, or throat.

Common side effects may include:

  • pain, itching, swelling, redness, bruising, hardening, pitting, or other skin changes where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect asfotase alfa?

Other drugs may interact with asfotase alfa, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Where can I get more information?

  • Your pharmacist can provide more information about asfotase alfa.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 1.02.

Date modified: October 14, 2016
Last reviewed: June 24, 2016