Natdac® is an inhibitor of the viral (hepatitis C virus) protein NS5A, which is used in the replication of hepatitis C virus within the liver cells (hepatocytes) and, thus, prevents the virus from entering infected hepatocytes into the blood. Thanks to this action, it is possible to prevent the spread of the virus in the body. Natdac® (daсlatasvir) is a highly specific direct action agent against hepatitis C virus (HCV) and has no pronounced activity against other RNA and DNA containing viruses, including human immunodeficiency virus (HIV). Natdac®, as an inhibitor of the nonstructural protein 5A (NS5A), a multifunctional protein required for HCV replication, suppresses two stages of the life cycle of the virus-viral RNA replication and virion assembly.
What is this medicine?
DACLATASVIR is an antiviral medicine that prevents hepatitis C virus (HCV) from multiplying in your body.
Daclatasvir is used to treat genotype 3 chronic hepatitis C in adults without cirrhosis. This medicine is given together with another drug called sofosbuvir.
Daclatasvir may also be used for purposes not listed in this medication guide.
What is the most important information I should know about daclatasvir?
Serious drug interactions can occur when certain medicines are used together with daclatasvir. Tell each of your healthcare providers about all medicines you use now, and any medicine you start or stop using.
What should I discuss with my healthcare provider before taking daclatasvir?
You should not use daclatasvir if you are allergic to it. If you take daclatasvir with sofosbuvir: There may be other reasons you should not take this combination treatment. Tell your doctor about all your medical conditions.
Some medicines can interact with daclatasvir and should not be used at the same time. Your doctor may need to change your treatment plan if you use any of the following drugs:
St. John's wort; or
seizure medicine--carbamazepine, phenytoin.
To make sure daclatasvir is safe for you, tell your doctor if you have:
liver problems other than hepatitis C;
if you also use amiodarone (a heart rhythm medicine); or
if you have received a liver transplant.
It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.
It is not known whether daclatasvir passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.
Daclatasvir is not approved for use by anyone younger than 18 years old.
How should I take daclatasvir?
Daclatasvir is usually taken for 12 weeks. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.
Daclatasvir must be given in combination with sofosbuvir and it should not be used alone.
You may take daclatasvir with or without food.
Hepatitis C is often treated with a combination of drugs. Use all medications as directed by your doctor. Read all patient information, medication guides, and instruction sheets provided to you. Ask your doctor or pharmacist if you have any questions.
Do not stop using any of your hepatitis C medicines without your doctor's advice. Do not change your doses or medication schedule without first asking your doctor. Every person with chronic hepatitis C should remain under the care of a doctor.
You will need frequent blood tests to check your liver function while using this medicine.
Store at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
What should I avoid while taking daclatasvir?
Taking daclatasvir will not prevent you from passing hepatitis C to other people. Do not have unprotected sex or share razors or toothbrushes. Talk with your doctor about safe ways to prevent HCV transmission during sex. Sharing drug or medicine needles is never safe, even for a healthy person.
Daclatasvir side effects
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
If you take daclatasvir with sofosbuvir 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; or
a light-headed feeling, like you might pass out.
Call your doctor at once if you have serious side effects of daclatasvir, including:
confusion, memory problems;
weakness, tiredness; or
general ill feeling.
Common side effects may include:
feeling weak or tired.
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.
Daclatasvir dosing information
Usual Adult Dose for Chronic Hepatitis C:
60 mg orally once a day for 12 weeks
-Sustained virologic response rates reduced in HCV genotype 3-infected patients with cirrhosis using this drug with sofosbuvir for 12 weeks; optimal duration of therapy has not been established for patients with cirrhosis.
-The manufacturer product information for sofosbuvir should be consulted.
Use: In combination with sofosbuvir, for the treatment of patients with chronic HCV genotype 3 infection
What other drugs will affect daclatasvir?
When you start or stop taking daclatasvir, your doctor may need to adjust the doses of any other medicines you take on a regular basis.
Many drugs can interact with daclatasvir, and some drugs should not be used together. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide. Tell your doctor about all medicines you use, and those you start or stop using during your treatment with daclatasvir. Give a list of all your medicines to any healthcare provider who treats you.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.