Intron A

Intron A is a prescription medication used to treat chronic hepatitis B, chronic hepatitis C, certain type of genital warts, hairy cell leukemia, malignant melanoma, AIDS-related Kaposi's sarcoma, and follicular lymphoma.

Intron A belongs to a group of drugs called interferons. This medication works by stopping viruses from dividing and by triggering our immune system to kill invading pathogens or tumors.

Intron A is a prescription medication used to treat:

• adults with a blood cancer called hairy cell leukemia
• adults with a type of skin cancer called malignant melanoma
• adults with some types of Follicular Non-Hodgkin's Lymphoma along with certain chemotherapy medicines
• adults with genital warts (condylomata acuminate), by injecting the medicine directly into the warts
• adults with a type of cancer caused by AIDS, called AIDS-related Kaposi's Sarcoma
• adults with chronic (lasting a long time) hepatitis C infection with stable liver problems
• chronic (lasting a long time) hepatitis C infection in people 3 years and older with stable liver problems (along with another medication)
• chronic (lasting a long time) hepatitis B infection in people 1 year and older with stable liver problems

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

WARNING

Alpha interferons, including Intron A, cause or aggravate fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. Patients should be monitored closely with periodic clinical and laboratory evaluations. Patients with persistently severe or worsening signs or symptoms of these conditions should be withdrawn from therapy. In many but not all cases these disorders resolve after stopping Intron A therapy.

Intron A can cause serious side effects that:

• may cause death, or
• may worsen certain serious diseases that you may already have.

Tell your healthcare provider right away if you have any of the symptoms listed below while taking Intron A. If symptoms get worse, or become severe and continue, your healthcare provider may tell you to stop taking Intron A permanently. In many, but not all people, these symptoms go away after they stop taking Intron A.

• low blood pressure
• fast heart rate or abnormal heart beats
• trouble breathing or chest pain
• heart attacks or heart muscle problems (cardiomyopathy)

• irritability (getting upset easily)
• depression (feeling low, feeling bad about yourself, or feeling hopeless)
• aggressive behavior
• thoughts of hurting yourself or others, or suicide
• former drug addicts may fall back into drug addiction or overdose

If you have these symptoms, your healthcare provider should carefully monitor you during treatment with Intron A and for 6 months after your last dose.

• fever
• chills
• bloody diarrhea
• burning or pain with urination
• urinating often
• coughing up mucus (phlegm) that is discolored (for example yellow or pink)

While taking Intron A, you should see a healthcare provider regularly for check-ups and blood tests to make sure that your treatment is working and to check for side effects.

Do not take Intron A if you:

• had a serious allergic reaction to another alpha interferon product or are allergic to any of the ingredients in Intron A. Ask your healthcare provider if you are not sure.
• have certain types of hepatitis (autoimmune hepatitis)
• have certain other liver problems

Talk to your healthcare provider before taking Intron A if you have any of these conditions.

Intron A may cause serious side effects including:

• See "Drug Precautions".
• Blood problems. Intron A can affect your bone marrow and cause low white blood cell and platelet counts. In some people, these blood counts may fall to dangerously low levels. If your blood cell counts become very low, you can get infections or have bleeding problems.
• Serious eye problems. Intron A may cause eye problems that may lead to vision loss or blindness. You should have an eye exam before you start taking Intron A. If you have eye problems or have had them in the past, you may need eye exams while taking Intron A. Tell your healthcare provider or eye doctor right away if you have any vision changes while taking Intron A.
• Thyroid problems. Some people develop changes in the function of their thyroid. Symptoms of thyroid problems include:
  • problems concentrating
  • feeling cold or hot all the time
  • changes in your weight
  • skin changes
• Blood sugar problems. Some people may develop high blood sugar or diabetes. If you have high blood sugar or diabetes before starting Intron A, talk to your healthcare provider before you take Intron A. If you develop high blood sugar or diabetes while taking Intron A, your healthcare provider may tell you to stop Intron A and prescribe a different medicine for you. Symptoms of high blood sugar or diabetes may include:
  • increased thirst
  • tiredness
  • urinating more often than normal
  • increased appetite
  • weight loss
  • your breath smells like fruit
• Lung problems including:
  • trouble breathing
  • pneumonia
  • inflammation of lung tissue
  • new or worse high blood pressure of the lungs (pulmonary hypertension). This can be severe and may lead to death. 

• Severe liver problems, or worsening of liver problems including liver failure and death. Symptoms may include:
  • nausea
  • loss of appetite
  • tiredness
  • diarrhea
  • yellowing of your skin or the white part of your eyes
  • bleeding more easily than normal
  • swelling of your stomach area (abdomen)
  • confusion
  • sleepiness
  • you cannot be awakened (coma)
• Serious allergic reactions and skin reactions. Symptoms may include:
  • itching
  • swelling of your face, eyes, lips, tongue, or throat
  • trouble breathing
  • anxiousness
  • chest pain
  • feeling faint
  • skin rash, hives, sores in your mouth, or your skin blisters and peels

• Swelling of your pancreas (pancreatitis) and intestines (colitis). Symptoms may include:
  • severe stomach area (abdomen) pain
  • severe back pain
  • nausea
  • vomiting
  • fever
• New or worsening autoimmune disease. Some patients taking Intron A develop autoimmune diseases (a condition where the body's immune cells attack other cells or organs in the body), including rheumatoid arthritis, systemic lupus erythematosus, sarcoidosis, and psoriasis. In some patients who already have an autoimmune disease, the disease may worsen while on Intron A.
• Nerve problems. People who take Intron A or other alpha interferon products with telbivudine (Tyzeka) can develop nerve problems such as continuing numbness, tingling, or burning sensation in the arms or legs (peripheral neuropathy). Call your healthcare provider if you have any of these symptoms.
• Growth problems in children. Weight loss and slowed growth are common in children during treatment with Intron A.
• Dental and gum problems.

Tell your healthcare provider right away if you have any of the symptoms listed above.

The most common side effects of Intron A include:

• Flu-like symptoms. Symptoms may include: headache, muscle aches, tiredness, and fever. Some of these symptoms may be decreased by injecting your Intron A dose in the evening. Talk to your healthcare provider about which over-the-counter medicines you can take to help prevent or decrease some of the symptoms.
• Tiredness. Many people become very tired during treatment with Intron A.
• Appetite problems. Nausea, loss of appetite, and weight loss can happen with Intron A.
• Skin reactions. Redness, swelling, and itching are common at the injection site.
• Hair thinning.

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

These are not all the side effects of Intron A. For more information, ask your healthcare provider or pharmacist.

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

Tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Intron A and certain other medicines may affect each other and cause side effects.

Especially tell your healthcare provider if you take:

• the anti-hepatitis B medicine telbivudine (Tyzeka)
• the anti-HIV medicine zidovudine (Retrovir)
• theophylline (Theo-24, Elixophyllin, Uniphyl, Theolair). Your healthcare provider may need to monitor the amount of theophylline in your body and make changes to your theophylline dose.

Know the medicines you take. Keep a list of them and show it to your healthcare provider and pharmacist when you get a new medicine.

Tell your healthcare provider if you are pregnant or plan to become pregnant. It is not known if Intron A will harm your unborn baby. You should use effective birth control during treatment with Intron A. Talk to your healthcare provider about birth control choices for you during treatment with Intron A. Tell your healthcare provider if you become pregnant during treatment with Intron A.

Tell your healthcare provider if you are breastfeeding or plan to breastfeed. It is not known if Intron A passes into your breast milk. You and your healthcare provider should decide if you will use Intron A or breastfeed. You should not do both.