Harvoni contains a combination of ledipasvir and sofosbuvir. Ledipasvir and sofosbuvir are antiviral medications that prevent the hepatitis C virus (HCV) from multiplying in your body.

Harvoni is used to treat chronic hepatitis C in adults and children who are at least 3 years old. Harvoni is sometimes given in combination with another medicine called ribavirin.

Harvoni treats specific genotypes of hepatitis C, and only in certain people. Use only the medications prescribed for you. Do not share your medicine with other people.

Harvoni is sometimes used in people who also have HIV. This medicine is not a treatment for HIV or AIDS.

If you've ever had hepatitis B, it may become active or get worse while using or after you stop using Harvoni. You may need frequent liver function tests for several months.

Harvoni is sometimes used in combination with other medication. Read the medication guide or patient instructions provided with each medication in your combination therapy. Do not change your doses or medication schedule without your doctor's advice.

Before taking this medicine

You should not use Harvoni if you are allergic to ledipasvir or sofosbuvir. If you take Harvoni with ribavirin: There may be other reasons you should not take this combination treatment. Tell your doctor about all your medical conditions.

To make sure Harvoni is safe for you, tell your doctor if you have ever had:

• hepatitis B (you may be tested for this before you take sofosbuvir);

• liver problems other than hepatitis (including a liver transplant);

• kidney disease (or if you are on dialysis);

• HIV or AIDS;

• a heart rhythm problem for which you take a medicine called amiodarone; or

• if you use a blood thinner (warfarin, Coumadin, Jantoven) and you have routine "INR" or prothrombin time tests.

Harvoni is sometimes used in combination with ribavirin. Both men and women using ribavirin should use effective birth control to prevent pregnancy. Ribavirin can harm an unborn baby or cause birth defects if the mother or father is using the medicine.

While taking ledipasvir and sofosbuvir with ribavirin, use effective birth control to prevent pregnancy, whether you are a man or a woman.

Keep using birth control for at least 6 months after your last dose of ribavirin. Tell your doctor right away if a pregnancy occurs while either the mother or the father is using ribavirin.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

Harvoni is not approved for use by anyone younger than 3 years old.

Take Harvoni exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

You may take Harvoni with or without food. Take the medicine at the same time each day.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you do not understand these instructions.

Do not chew the oral pellets. To take with food, you may mix the pellets with a non-acidic soft food (pudding, chocolate syrup, mashed potato, ice cream) that is at room temperature or below. Swallow the mixture without chewing, no more than 30 minutes after mixing. Do not save the mixture for later use.

Ledipasvir and sofosbuvir doses are based on weight (especially in children and teenagers). Your dose needs may change if you gain or lose weight.

You will need frequent blood tests to check your liver function.

If you've ever had hepatitis B, this virus may become active or get worse while you are using this medicine or in the months after you stop. You may need liver function tests for several months after your last dose.

You should not stop using Harvoni suddenly. Stopping suddenly could make your condition harder to treat with hepatitis C antiviral medicine.

Use all medications as directed and read all medication guides you receive. Do not change your dose or dosing schedule without your doctor's advice. Every person with chronic hepatitis C should remain under the care of a doctor.

Store this medicine in the original container at room temperature away from moisture and heat. Do not open the packet of oral pellets until you are ready to use the medicine.

You should not use Harvoni if you are allergic to ledipasvir or sofosbuvir. If you take Harvoni with ribavirin: There may be other reasons you should not take this combination treatment. Tell your doctor about all your medical conditions.

To make sure Harvoni is safe for you, tell your doctor if you have ever had:

• hepatitis B (you may be tested for this before you take sofosbuvir);

• liver problems other than hepatitis (including a liver transplant);

• kidney disease (or if you are on dialysis);

• HIV or AIDS;

• a heart rhythm problem for which you take a medicine called amiodarone; or

• if you use a blood thinner (warfarin, Coumadin, Jantoven) and you have routine "INR" or prothrombin time tests.

Harvoni is sometimes used in combination with ribavirin. Both men and women using ribavirin should use effective birth control to prevent pregnancy. Ribavirin can harm an unborn baby or cause birth defects if the mother or father is using the medicine.

While taking ledipasvir and sofosbuvir with ribavirin, use effective birth control to prevent pregnancy, whether you are a man or a woman.

Keep using birth control for at least 6 months after your last dose of ribavirin. Tell your doctor right away if a pregnancy occurs while either the mother or the father is using ribavirin.

It may not be safe to breastfeed while using this medicine. Ask your doctor about any risk.

Harvoni is not approved for use by anyone younger than 3 years old.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Get your prescription refilled before you run out of medicine completely.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Ask your doctor before using an antacid or stomach acid reducing medicine. Use only the type and amount your doctor recommends.

Using this medicine will not prevent your disease from spreading. Do not have unprotected sex or share razors or toothbrushes. Talk with your doctor about safe ways to prevent hepatitis C transmission during sex. Sharing drug or medicine needles is never safe, even for a healthy person.

Get emergency medical help if you have signs of an allergic reaction to Harvoni: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have new or worsening symptoms such as:

• right-sided upper stomach pain;

• vomiting, loss of appetite; or

• jaundice (yellowing of the skin or eyes), and not feeling well.

If you take Harvoni and you also take a heart rhythm medicine called amiodarone: This combination of medicines can cause dangerous side effects on your heart. Get medical help right away if you take these medicines and you have:

• very slow heartbeats, chest pain, shortness of breath;

• confusion, memory problems; or

• weakness, extreme tiredness, light-headed feeling (like you might pass out).

Common Harvoni side effects may include:

• weakness;

• headache; or

• tired feeling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

When you start or stop taking Harvoni, your doctor may need to adjust the doses of any other medicines you take on a regular basis.

If you also take an antacid: Wait at least 4 hours after taking the antacid before you take ledipasvir and sofosbuvir.

If you also take a stomach acid reducer: You may need to wait 12 hours after taking the stomach acid medicine before you take ledipasvir and sofosbuvir. This includes cimetidine, famotidine, nizatidine, ranitidine, Axid, Pepcid, Tagamet, Zantac, and others.

Ask a doctor or pharmacist before taking certain other stomach acid reducers such as esomeprazole, lansoprazole, omeprazole, pantoprazole Nexium, Prevacid, Prilosec, Protonix, and others.

Many drugs can interact with ledipasvir and sofosbuvir. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.