Parathyroid hormone injection may cause osteosarcoma (bone cancer) in laboratory rats. It is possible that parathyroid hormone injection may also increase the chances that humans will develop this cancer. Tell your doctor if you or a family member has or has ever had a bone disease such as Paget's disease, bone cancer, or a cancer that has spread to the bone, and if you have or have ever had radiation therapy of the bones, high levels of alkaline phosphatase (an enzyme in the blood), or if you are a child or young adult whose bones are still growing. If you experience any of the following symptoms, call your doctor immediately: pain in any area of the body that does not go away or new or unusual lumps or swelling under the skin that are tender to touch.
Because of the risk of osteosarcoma with this medication, parathyroid hormone injection is only available through a special program called Natpara REMS. You, your doctor, and your pharmacist must be enrolled in this program before you can receive parathyroid hormone injection. All people who are prescribed parathyroid hormone injection must have a prescription from a doctor who is registered with Natpara REMS and have the prescription filled at a pharmacy that is registered with Natpara REMS in order to receive this medication. Ask your doctor for more information about this program and how you will receive your medication.
Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with parathyroid hormone injection and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer's website to obtain the Medication Guide.
Talk to your doctor about the risks of receiving parathyroid hormone injection.
Why is this medication prescribed?
Parathyroid hormone injection is used along with calcium and vitamin D to treat low levels of calcium in the blood in people with certain types of hypoparathyroidism (condition in which the body does not produce enough parathyroid hormone [PTH; a natural substance needed to control the amount of calcium in the blood].) Parathyroid hormone injection should not be used to treat low levels of calcium in the blood in people whose condition can be controlled by calcium and vitamin D alone. Parathyroid hormone injection is in a class of medications called hormones. It works by causing the body to absorb more calcium into the blood.
How should this medicine be used?
Parathyroid hormone injection comes as a powder to be mixed with a liquid and injected subcutaneously (under the skin). It is usually given once a day into your thigh. Use parathyroid hormone injection at around the same time every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use parathyroid hormone injection exactly as directed. Do not use more or less of it or use it more often than prescribed by your doctor.
You can inject parathyroid hormone injection yourself or have a friend or relative perform the injections. Before you use parathyroid hormone injection yourself the first time, carefully read the manufacturer's instructions. Ask your doctor or pharmacist to show you or the person who will be injecting the medication how to mix the medication properly and how to inject it. Be sure to ask your pharmacist or doctor if you have any questions about how to inject this medication.
Parathyroid hormone injection comes in a cartridge to be mixed in a separate mixing device and then placed in a pen injector. Do not transfer the medication from the cartridge to a syringe. After mixing, each medicine cartridge can be used for 14 doses. Throw away the cartridge 14 days after it was mixed even if it is not empty. Do not throw away the pen injector. It can be used for up to 2 years by changing the medication cartridge every 14 days.
Do not shake the medication. Do not use the medication if it has been shaken.
Always look at your parathyroid hormone injection before you inject it. It should be colorless. It is normal to see small particles in the liquid.
You should inject the medication into a different thigh each day.
Be sure you know what other supplies, such as needles, you will need to inject your medication. Ask your doctor or pharmacist what type of needles you will need to inject your medication. Never reuse needles and never share needles or pens. Always remove the needle right after you inject your dose. Throw away needles in a puncture-resistant container. Ask your doctor or pharmacist how to dispose of the puncture-resistant container.
Your doctor may start you on a low dose of parathyroid hormone injection and gradually adjust your dose depending on how your body responds to the medication. Your doctor may also change your doses of calcium and vitamin D while you are taking this medication.
Parathyroid hormone injection controls hypoparathyroidism but does not cure it. Continue to use parathyroid hormone injection even if you feel well. Do not stop using parathyroid hormone injection without talking to your doctor. If you suddenly stop using parathyroid hormone injection, you may develop severe low levels of calcium in the blood. Your doctor will probably decrease your dose gradually.
Other uses for this medicine
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What special precautions should I follow?
Before using parathyroid hormone injection,
- tell your doctor and pharmacist if you are allergic to parathyroid hormone, any other medications, or any of the ingredients in parathyroid hormone injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: alendronate (Fosamax), calcium supplements, digoxin (Lanoxin), and vitamin D. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had kidney disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using parathyroid hormone injection, call your doctor.
- if you are having surgery, including dental surgery, tell the doctor or dentist that you are using parathyroid hormone injection.
What special dietary instructions should I follow?
Talk to your doctor about eating foods containing calcium or vitamin D while using this medication.
What should I do if I forget a dose?
Use the missed dose as soon as you remember it and call your doctor immediately. Your doctor may tell you to take more calcium. Continue your regular dosing schedule the next day.
What side effects can this medication cause?
Parathyroid hormone injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- tingling, tickling, or burning feeling of the skin
- sense of numbness
- pain in the arms, legs, joints, stomach, or neck
Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:
- symptoms of high blood calcium: nausea, vomiting, constipation, low energy, or muscle weakness
- symptoms of low blood calcium: tingling of lips, tongue, fingers and feet; twitching of face muscles; cramping of feet and hands; seizures; depression; or problems thinking or remembering
Parathyroid hormone injection may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I know about storage and disposal of this medication?
Your healthcare provider will tell you how to store your medication. Keep this medication in the container it came in, tightly closed, and out of reach of children. Unmixed medication cartridges should be stored in the package provided in the refrigerator. After mixing, the medication cartridge should be stored in the pen injector in the refrigerator. Store away from heat and light. Do not freeze the medication cartridges. Do not use parathyroid hormone injection if it has been frozen. The mixing device and empty pen injector can be stored at room temperature.
Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.
In case of emergency/overdose
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
What other information should I know?
Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests before and during your treatment to check your body's response to parathyroid hormone injection.
Do not let anyone else use your medication. Ask your pharmacist any questions you have about refilling your prescription.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.