Interferon gamma-1b injection is used to reduce the frequency and severity of serious infections in people with chronic granulomatous disease (an inherited immune system disease). It is also used to slow down worsening of their condition in people with severe, malignant osteopetrosis (an inherited bone disease). Interferon gamma-1b is in a class of medications called immunomodulators. It is not known exactly how interferon gamma-1b works to treat chronic granulomatous disease and osteopetrosis.

Interferon gamma-1b injection comes as a solution to inject subcutaneously (just under the skin) three times a week, for example, every Monday, Wednesday, and Friday. Inject interferon gamma-1b injection at around the same time of day each time you inject it. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use interferon gamma-1b injection exactly as directed. Do not inject more or less of it or inject it more often than prescribed by your doctor.

You will receive your first dose of interferon gamma-1b in your doctor's office. Then you can inject interferon gamma-1b yourself or have a friend or relative give the injections. Before you use interferon gamma-1b yourself the first time, read the written instructions that come with it. Ask your doctor or pharmacist to show you or the person who will be injecting the medication how to inject it.

Never reuse or share syringes, needles, or vials of medication. Throw away used needles and syringes in a puncture-resistant container and throw away used vials of medication in the trash. Talk to your doctor or pharmacist about how to dispose of the puncture-resistant container.

You can inject interferon gamma-1b in your upper arms, stomach area, or your thighs. Choose a different spot each time you inject your medication. Do not inject your medication into skin that is irritated, bruised, reddened, infected, or scarred.

Your doctor or pharmacist will give you the manufacturer's patient information sheet when you begin treatment with interferon gamma-1b and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions.

Before receiving interferon gamma-1b injection,

• tell your doctor and pharmacist if you are allergic to interferon gamma-1b injection, products made from the E. colibacteria, any other medications, or any of the other ingredients in interferon gamma-1b injection. Ask your pharmacist for a list of the ingredients.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. 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 seizures, a low number of red or low white blood cells, heart failure, an irregular heartbeat, or heart or liver disease.
• tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while receiving interferon gamma-1b injection, call your doctor.
• you should know that you may have flu-like symptoms such as headache, fever, chills, muscle aches, and tiredness after your injection. Your doctor may tell you to take acetaminophen (Tylenol), an over-the-counter pain and fever medication, to help with these symptoms. Talk to your doctor if these symptoms are difficult to manage or become severe.

If you miss a dose of interferon gamma-1b injection, do not increase your dose or give two injections to make up for the missed dose.Call your doctor if you miss a dose and have questions about what to do.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Keep this medication in the refrigerator and out of reach of children. Interferon gamma-1b may be left at room temperature for no longer than 12 hours. Do not freeze interferon gamma-1b.

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.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unless your doctor tells you otherwise, continue your normal diet.

Interferon gamma-1b injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• extreme tiredness
• diarrhea
• nausea
• vomiting
• muscle or joint pain
• dizziness
• problems with walking
• confusion
• bruising, redness, swelling, bleeding, or irritation at the injection spot

Some side effects can be serious. If you experience any of these symptoms or those listed in the SPECIAL PRECAUTIONS section, stop the medication and call your doctor immediately or get emergency medical treatment:

• rash
• itching
• difficulty breathing or swallowing
• hives
• swelling of the eyes, face, mouth, tongue, and throat

Interferon gamma-1b injection may cause other side effects. Call your doctor if you have any unusual problems while receiving 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).

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Keep all appointments with your doctor and the laboratory.

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.

• Actimmune®