Daclatasvir
2 medicines
Daclatasvir is an antiviral tablet used with other medicines to cure chronic hepatitis C. It can reactivate hepatitis B in people who carry both viruses, so hepatitis B testing is required before starting treatment.
Key facts
- Daclatasvir is a direct-acting antiviral that blocks a hepatitis C virus protein called NS5A. It is always combined with another antiviral, usually sofosbuvir, and is never given alone.
- A typical course lasts 12 weeks, taken as one tablet daily, and cures the large majority of people who complete it.
- Daclatasvir can reactivate hepatitis B virus in people who carry both infections, sometimes causing serious liver damage. Your doctor should test you for hepatitis B before you start.
- Seek urgent care for yellowing of the skin or eyes, severe fatigue, or unexplained bruising or bleeding.
What daclatasvir treats
Daclatasvir treats chronic hepatitis C virus infection, a long-term liver infection that can otherwise lead to cirrhosis and liver cancer over years. Combined with another antiviral such as sofosbuvir, with or without ribavirin, it is used across the main hepatitis C genotypes to clear the virus from the blood and let the liver recover.
How daclatasvir works
Hepatitis C needs a protein called NS5A to assemble new copies of itself inside liver cells. Daclatasvir binds to this protein and blocks it, stopping the virus from replicating. Used together with a second antiviral that blocks the virus by a different mechanism, the combination clears the infection in most people and makes resistance much less likely than either drug alone.
Before you take it
- Tell your doctor if you have ever had hepatitis B, since daclatasvir-based treatment can reactivate it; hepatitis B testing is done before you start and monitoring continues during and after treatment.
- Avoid strong enzyme-inducing medicines such as rifampicin, certain anticonvulsants (phenytoin, carbamazepine), and St John's wort; they can lower daclatasvir levels enough to make treatment fail.
- Tell your doctor about amiodarone if you take it for a heart rhythm problem; combined with daclatasvir and sofosbuvir it has caused dangerously slow heart rates.
- Significant liver impairment may need a different regimen or dose; discuss your liver test results with your doctor.
Side effects
Common effects include headache, fatigue, nausea, and mild diarrhoea, usually manageable and easing as treatment continues.
Stop and seek urgent medical care for:
- Yellowing of the skin or eyes, dark urine, or severe fatigue (possible liver problem).
- Unusual bruising or bleeding.
- A very slow or irregular heartbeat, dizziness, or fainting, especially if you also take amiodarone.
- A severe allergic reaction: rash, swelling, or difficulty breathing.
Safety essentials
- Daclatasvir-based treatment can reactivate hepatitis B virus in people who carry both infections; hepatitis B testing before starting is essential, and your doctor will monitor liver function during and after treatment.
- Never take daclatasvir alone. It is only effective, and resistance is only avoided, when combined with a second antiviral as prescribed.
- Avoid starting or stopping any other medicine, including herbal supplements, without checking for interactions; several common drugs can make daclatasvir ineffective or raise its levels.
This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.