Simeprevir is used along with ribavirin (Copegus, Rebetol) and peginterferon alfa (Pegasys) to treat chronic hepatitis C (an ongoing viral infection that damages the liver). Simeprevir is in a class of medications called protease inhibitors. It works by decreasing the amount of hepatitis C virus (HCV) in the body. Simeprevir may not prevent the spread of hepatitis C to other people.

Side Effects Of Simeprevir

Simeprevir may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • itching
  • nausea
  • muscle pain

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

  • difficulty breathing
  • rash
  • mouth sores or ulcers
  • red or swollen eyes (“pink eye”)

Simeprevir may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Warnings & Precautions

Before taking simeprevir:

  • tell your doctor and pharmacist if you are allergic to simeprevir, sulfa drugs, any other medications, or any of the ingredients in simeprevir capsules. Ask your pharmacist or check the manufacturer’s patient information 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: certain antifungal medications such as fluconazole (Diflucan), itraconazole (Onmel, Sporanox), ketoconazole, posaconazole (Noxafil), or voriconazole (Vfend); calcium channel blockers such as amlodipine (Norvasc), diltiazem (Cardizem, Dilacor XR, Tiazac), felodipine, nicardipine (Cardene), nifedipine (Adalat, Procardia), nisoldipine (Sular), or verapamil (Calan, Verelan, others); certain medications for high cholesterol such as atorvastatin (Lipitor, in Caduet), lovastatin (Altoprev), pitavastatin (Livalo), pravastatin (Pravachol), rosuvastatin (Crestor), or simvastatin (Flolipid, Zocor, in Vytorin); cisapride (Propulsid) (not available in the U.S.); clarithromycin (Biaxin, in Prevpac); medications containing cobicistat (Stribild); erythromycin (E.E.S., Eryc, Ery-tab, others), certain medications for HIV such as atazanavir (Reyataz), darunavir (Prezista), delavirdine (Rescriptor), efavirenz (Sustiva), etravirine (Intelence), fosamprenavir (Lexiva), indinavir (Crixivan), lopinavir (Kaletra), nelfinavir (Viracept), nevirapine (Viramune), ritonavir (Norvir), saquinavir (Invirase), or tipranavir (Aptivus); certain medications for irregular heartbeat such as amiodarone (Nexterone, Pacerone), disopyramide (Norpace), flecainide (Tambocor), mexiletine , propafenone (Rythmol SR), or quinidine (in Nuedexta); cyclosporine (Gengraf, Neoral, Sandimmune); dexamethasone; digoxin (Lanoxin); ledipasvir (Harvoni); midazolam taken by mouth; rifabutin (Mycobutin); rifampin (Rifadin, Rimactane, in Rifamate, in Rifater); rifapentine (Priftin); certain medications for seizures such as carbamazepine (Epitol, Equetro, Tegretol), oxcarbazepine (Trileptal), phenobarbital, or phenytoin (Dilantin, Phenytek); sildenafil (only Revatio brand used for lung disease); sirolimus (Rapamune); tacrolimus (Prograf); tadalafil (only Adcirca brand used for lung disease); telithromycin (Ketek); triazolam (Halcion) taken by mouth; vardenafil (Levitra, Staxyn), or warfarin (Coumadin, Jantoven). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with simeprevir, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
  • tell your doctor what herbal products you are taking, especially milk thistle or St. John’s wort. You should not take milk thistle or St. John’s wort during your treatment with simeprevir.
  • tell your doctor if you have had a liver transplant if you are receiving phototherapy, if you are of East Asian descent, and if you have or have ever had any type of liver disease other than hepatitis C.
  • tell your doctor if you are pregnant, plan to become pregnant, or can possibly become pregnant. If you are male, tell your doctor if your partner is pregnant, plans to become pregnant, or can possibly become pregnant. Simeprevir must be taken with ribavirin which can seriously harm the fetus. You must use two methods of birth control to prevent pregnancy in you or your partner during treatment with these medications and for 6 months after your treatment. Talk to your doctor about which methods you should use; hormonal contraceptives (birth control pills, patches, implants, rings, or injections) may not work well in women who are taking these medications. You or your partner must be tested for pregnancy prior to treatment, every month during your treatment, and for 6 months after your treatment. If you or your partner becomes pregnant while taking these medications, call your doctor immediately.
  • tell your doctor if you are breastfeeding.
  • plan to avoid unnecessary or prolonged exposure to sunlight and to wear protective clothing, sunglasses, a hat, and sunscreen during your treatment with simeprevir. Also avoid the use of tanning beds, sunlamps, or other types of light therapy during your treatment. Simeprevir may make your skin sensitive to sunlight. Call your doctor right away if you experience a severe sunburn or burning, redness, swelling, blisters on your skin, or red or inflamed eyes.

Simeprevir Dosage

Simeprevir comes as a capsule to take by mouth. It is usually taken with food once a day. Take simeprevir 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. Take simeprevir exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Swallow the capsules whole; do not split, chew, or crush them.

You will take simeprevir with peginterferon alfa and ribavirin for 12 weeks. Then you will stop taking simeprevir and will take peginterferon and ribavirin for an additional 12 or 36 weeks. The length of your treatment depends on whether you have received prior treatment for hepatitis C, how you responded to prior treatment, how you respond to the medications, and whether you experience severe side effects. Continue to take simeprevir, peginterferon alfa, and ribavirin as long as they are prescribed by your doctor. Do not stop taking any of these medications without talking to your doctor even if you are feeling well.

Ask your pharmacist or doctor for a copy of the manufacturer’s information for the patient.


Do not let anyone else take 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.


All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.