Generic Copegus

Common use

Copegus is used together with an interferon (such as PegIntron or Intron A) to treat chronic hepatitis C which is a disease of the liver. This is a drug for the patients who have not been treated with interferon previously or who have had a return of hepatitis C following successful treatment with interferon. It helps the immune system fight the hepatitis C virus, and make it harder for the virus to reproduce within the body. Copegus belongs to the antivirals.



Dosage and direction

The usual dose of Copegus per day is 800 mg, 1,000 mg, or 1,200 mg i orally in two divided doses (morning and evening) with food for 24 or 48 weeks. The dose and duration of treatment depend on your condition, on body weight, on baseline disease characteristics, response to therapy and tolerability of the regimen. Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label. It should be taken consistently. For example, it should be taken at the same time or times each day and each time.



Precautions

Copegus may decrease the number of red blood cells in your body (anemia) and it can be life-threatening in people who have heart disease or circulation problems. Careful consideration is advised if Copegus is used in patients with heart or circulation problems since the anemia may aggravate these conditions. Your blood will need to be tested often. Also your vision, liver function and thyroid function may also need to be tested. Visit your doctor regularly. Call your doctor at once if you have pale or yellowed skin, dark colored urine, fever, confusion, chest pain, weakness, or trouble breathing. Copegus may cause birth defects and/or death in unborn babies that are exposed to it during pregnancy. If you or your sexual partner are or may be pregnant, do not take Copegus, and contact your doctor immediately. Women and men who are taking Copegus must avoid pregnancy during treatment with this drug and for 6 months after this medication has been stopped. Consult your doctor or pharmacist for more information.



Contraindications

Before taking Copegus you should talk with your doctor if you are allergic to peginterferon alfa-2a, any other interferon, ribavirin, polyethylene glycol, or to any of the ingredients of the medication, if you are an infant, breast-feeding, pregnant or has a pregnant partner. Also in the way if you have decompensated liver disease, hemoglobinopathies (thalassemia, sickle-cell anemia), HIV-HCV (human immunodeficiency virus and hepatitis C virus) with cirrhosis and a baseline Child-Pugh score greater than or equal to 6. And you should discuss with your doctor if you have a severe psychiatric disorder, autoimmune diseases (including autoimmune hepatitis), thyroid problems not controlled by medication even in the past.



Possible side effects

The most common side effect of Copegus is a flu-like syndrome consisting of body aches and pains, fever, chills, headache and malaise. The most serious side effect is anemia. Patients with certain types of heart disease should not use Copegus. This may make your condition worse and can lead to a possibly fatal heart attack. Copegus should be avoided among patients who have severe kidney disease and have lost most of their kidneys' function. Therapy with Copegus and interferon may aggravate psychiatric conditions or may cause a psychiatric condition such as depression, suicidal ideation, psychosis, aggressive behavior, hallucinations, or violent behavior. Patients should be closely monitored for the development of these psychiatric conditions. Therapy has caused abnormalities of the thyroid gland. If these abnormalities persist and cannot be controlled by medication, it may be necessary to finish this therapy. Other possible side effects that may occur during therapy with Copegus are fatigue, weakness, nausea, anorexia, heartburn, insomnia, irritability, difficulty breathing, rash, itching, and alterations in taste perception.



Drug interactions

If Copegus is used with other antiviral drugs with similar mechanisms of action it may cause a condition in which lactic acid accumulates in the blood (lactic acidosis). This situation can lead to serious medical problems. Also do not take Copegus with antiviral drugs that used to manage HIV infection (zidovudine (Retrovir), zalcitabine (Hivid) or stavudine (Zerit)).



Missed dose

If you miss a dose of Copegus, take the missed dose as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.



Overdose

Overdose symptoms may include easy bruising or bleeding, urinating less than usual or not at all, chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, or a general ill feeling. If you experience something from list above you need emergency medical attention.



Storage

Store Copegus in the refrigerator, protect them from light, and keep them out of the reach of children. Do not freeze, shake, or use them past the expiry date.



Disclaimer

We provide only general information about medications which does not cover all directions, possible drug integrations, or precautions. Information at the site cannot be used for self-treatment and self-diagnosis. Any specific instructions for a particular patient should be agreed with your health care adviser or doctor in charge of the case. We disclaim reliability of this information and mistakes it could contain. We are not responsible for any direct, indirect, special or other indirect damage as a result of any use of the information on this site and also for consequences of self-treatment.

Clinical Verification

Last Clinically Updated: August 15, 2026

Written By

Dr. Elena Vance, PharmD

Clinical Specialist in Neuropharmacology

Fact Checked By

Marcus Thorne, MS

Biomedical Data & FDA Label Verification

Medically Reviewed By

Dr. Arthur Campbell, MD

Board-Certified Psychiatrist (ABPN)