Peginterferon beta-1a (Subcutaneous)
Generic name: peginterferon beta-1a (peg-in-ter-FEER-on BAY-ta-1-a)
Drug class: Interferons
Medically reviewed by Drugs.com. Last updated on Sep 23, 2021.
Commonly used brand name(s)
In the U.S.
- Plegridy Pen
- Plegridy Pen Starter Pack
Available Dosage Forms:
Therapeutic Class: Immunological Agent
Pharmacologic Class: Interferon, Beta (class)
Uses for peginterferon beta-1a
Peginterferon beta-1a injection is used to treat the relapsing forms of multiple sclerosis (MS), including clinically isolated syndrome, relapsing-remitting disease, and active secondary progressive disease. Peginterferon beta-1a will not cure MS, but it may slow some of the disabling effects and decrease the number of relapses of the disease. Peginterferons are natural substances that are produced in the body to help fight infections. Peginterferon beta-1a is a synthetic (man-made) version of these substances.
Peginterferon beta-1a is available only with your doctor's prescription.
Before using peginterferon beta-1a
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For peginterferon beta-1a, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to peginterferon beta-1a or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of peginterferon beta-1a injection in the pediatric population. Safety and efficacy have not been established.
Although appropriate studies on the relationship of age to the effects of peginterferon beta-1a injection have not been performed in the geriatric population, geriatric-specific problems are not expected to limit the usefulness of peginterferon beta-1a injection in the elderly.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Interactions with food/tobacco/alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other medical problems
The presence of other medical problems may affect the use of peginterferon beta-1a. Make sure you tell your doctor if you have any other medical problems, especially:
- Anemia or
- Autoimmune disorders (eg, autoimmune hepatitis, idiopathic thrombocytopenia) or
- Bleeding problems or
- Congestive heart failure or
- Depression or mental health problems, history of or
- Heart disease (eg, cardiomyopathy) or
- Liver disease (including hepatitis) or
- Seizures, history of or
- Thyroid problems—Use with caution. May make these conditions worse.
- Infection—May decrease your body's ability to fight an infection.
- Kidney disease, severe—Use with caution. The effects may be increased because of slower removal of the medicine from the body.
Proper use of peginterferon beta-1a
A nurse or other trained health professional will give you peginterferon beta-1a. You may also be taught how to give your medicine at home. Peginterferon beta-1a is given as a shot under your skin (usually in the stomach, back of the upper arm, or thighs) or into your muscle (usually in the left and right thighs).
If you are injecting peginterferon beta-1a yourself, use it exactly as directed by your doctor. Do not change your dose or dosing schedule without checking first with your doctor. The exact amount of medicine you need has been carefully worked out. Using too much will increase the risk for side effects, while using too little may not improve your condition.
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 irritated, reddened, bruised, infected, or scarred in any way.
Check the injection site after 2 hours for redness, swelling, and tenderness.
Each package of the medicine contains a Medication Guide and patient instructions. Read the instructions carefully and make sure you understand:
- How to prepare the injection.
- How to use disposable syringes or pen.
- How to store the syringes or pen.
Allow the medicine to warm to room temperature for 30 minutes before you use it. Do not warm it in any other way.
You might not use all of the medicine in each prefilled syringe or pen. Use each prefilled syringe and pen only one time. Do not save an open syringe or pen.
You may also receive other medicines (fever medicine, pain medicine) to help prevent or lessen flu-like symptoms (eg, fever, cough, chills, body aches) that may occur during treatment with peginterferon beta-1a.
The dose of peginterferon beta-1a will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of peginterferon beta-1a. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For injection dosage form (solution):
- For multiple sclerosis:
- Adults—63 micrograms (mcg) injected under the skin or into a muscle on Day 1. Your doctor will increase your dose to 94 mcg after 14 days, reaching the full dose of 125 mcg on Day 29 (after another 14 days). Then, 125 mcg injected under your skin or into your muscle every 14 days.
- Children—Use and dose must be determined by your doctor.
- For multiple sclerosis:
Peginterferon beta-1a needs to be given on a fixed schedule. If you miss a dose or forget to use your medicine, call your doctor or pharmacist for instructions.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Store in the refrigerator. Do not freeze.
You may also store peginterferon beta-1a at room temperature, away from heat and direct light, for up 30 days. Throw away any unused medicine after 30 days.
Precautions while using peginterferon beta-1a
It is very important that your doctor check your progress at regular visits to make sure that peginterferon beta-1a is working properly. Blood tests may be needed to check for unwanted effects.
Check with your doctor right away if you have pain or tenderness in the upper stomach, pale stools, dark urine, loss of appetite, nausea, vomiting, or yellow eyes or skin. These could be symptoms of a serious liver problem.
Peginterferon beta-1a may cause some people to be anxious, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you or your caregiver notice any of these side effects, tell your doctor right away.
Peginterferon beta-1a may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and require immediate medical attention. Call your doctor right away if you have a rash, itching, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you are using peginterferon beta-1a.
The tip cap of the prefilled syringe for intramuscular injection contains dry natural rubber (a derivative of latex), which may cause allergic reactions in people who are sensitive to latex. Tell your doctor if you have a latex allergy before you start using peginterferon beta-1a.
Peginterferon beta-1a may cause redness, pain, or swelling at the injection site. Some patients have developed serious skin infection or damage (necrosis), including a permanent depression under the skin at the injection site. Contact your doctor right away if you notice depressed or indented skin, blue-green to black skin discoloration, or pain, redness, or sloughing (peeling) of the skin.
Peginterferon beta-1a commonly causes a flu-like reaction, with aching muscles, chills, fever, headaches, joint pain, and nausea. Using your shot at bedtime may allow you to sleep through the symptoms. Your doctor may want you to take medicine to help control the pain or fever (eg, acetaminophen or ibuprofen). Carefully follow your doctor's instructions about how to prevent or treat these symptoms.
If you are rapidly gaining weight, chest pain or discomfort, extreme tiredness or weakness, irregular breathing, irregular heartbeat, excessive swelling of the hands, wrist, ankles, or feet, or trouble breathing, check with your doctor immediately. These may be symptoms of heart problems or your body keeping too much water.
Peginterferon beta-1a may lower the number of white blood cells in the blood. This will increase your chance of getting an infection. It can also lower the number of platelets in the blood. Platelets are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:
- If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
- Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
- Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
- Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
- Be careful not to cut yourself when you are using sharp objects, such as a safety razor or fingernail or toenail cutters.
- Avoid contact sports or other situations where bruising or injury could occur.
Peginterferon beta-1a side effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
- Blue-green to black skin discoloration
- extremely high fever or body temperature
- fast, shallow breathing
- fast, weak heartbeat
- general feeling of discomfort or illness
- joint pain
- muscle aches, cramps, and pains
- pale, clammy skin
- runny nose
- sore throat
- trouble sleeping
- unusual tiredness or weakness
- Dark urine
- decreased appetite
- itching skin
- light-colored stools
- stomach pain
- yellow eyes or skin
- Chest tightness
- difficulty with swallowing
- hives or welts, skin rash
- large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- redness of the skin
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- Difficulty with moving
- itching, rash, redness, soreness, swelling, or warmth at the injection site
- lack or loss of strength
- muscle aches, cramps, pains, or stiffness
- pain, redness, or sloughing of the skin at the injection site
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Frequently asked questions
- What are the new drugs used for multiple sclerosis (MS)?
- What is Plegridy used for and is it an immunosuppressant?
- How do you use the Plegridy pen and where do you inject?
More about peginterferon beta-1a
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- En Español
- 11 Reviews
- Drug class: interferons
- Other brands
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