What are the side effects?


What side effects could I get from treatment?


The drugs used in treatment of Hepatitis B are very powerful.  Thankfully, serious side effects from the main two antiviral drugs are rare.  The two main antiviral drugs used in treatment of Hepatitis B are Tenofovir and Entecavir.


 Side effects of Tenofovir can include:

  • Diarrhoea
  • Feeling sick (nausea)
  • Being sick
  • Skin rash
  • Feeling weak
  • Dizziness
  • In rare cases, kidney problems

 Side effects of Entecavir can include:

  • Feeling sick (nausea)
  • Being sick
  • Insomnia
  • Dizziness

 If you feel dizzy, avoid driving or using tools and machinery.


Lactic Acidosis


In some rare cases these drugs can cause a condition called Lactic Acidosis.  This is a build up of lactic acid in your blood. It is potentially serious if left untreated.


Initial warning signs and symptoms of lactic acidosis include:

  • Feeling very weak or tired
  • Having unusual muscle pain
  • Breathing difficulties
  • Having stomach pain along with feeling or being sick
  • Feeling unusually cold, especially in your arms or legs
  • Feeling dizzy or light headed
  • Having a fast or irregular heart beat

If you experience any of these symptoms, contact the doctor in charge of your care for advice.


Pegylated interferon alfa: this is usually only prescribed for Hepatitis B infection if you have a high level of the virus in your body and is prescribed over a period of between three and six months.  Possible side effects may include:

  • Flu like symptoms
  • Fatigue
  • Fever
  • Muscle pain
  • Joint pain
  • Stiffness
  • Headaches
  • Depression
  • Anxiety
  • Stress

For some people, Pegylated Interferon Alfa can cause these side effects to be persistent and wide ranging, meaning that they may have to be taken off this treatment and an alternative treatment be used.  For others these symptoms will tend to become less severe after the first month of treatment and can be managed. It is a good idea to think about or plan whether you will need any help or support when you are living with treatment.

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Sexual Health and Blood Borne Virus Framework 

The Scottish Government has published the Sexual Health and Blood Borne Virus Framework to tackle Hepatitis B in Scotland.
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