Your post suggests he has had bleeding oesophagal varices caused restricted blood flow through the liver.
He is O.K for the medication if his liver itself is 'compensated' meaning still performing it's key functions.The doctor will have doubtless considered this and concluded that he can go ahead.
Other members of this forum who have varices (albeit non- bleeding) are currently undergoing treatment.
The SOC, Standard Treatment of Care, for genotype 3 is weekly Injections of Peginterferon (Roche brand Pegasys) and daily pills of Ribavirin (generic or Roche brand Copegus) for 6 months.
You can also check on how the medications are applied etc. on www.pegasys.com. This will give you a bit more insight on the medications.
(I used to live in Indonesia and we used to go to Singapore for medical care. My mother had MDS which progressed to leukemia and was treated at Private Gleneagles Hospital. You have amazing doctors and medical care there! Besides that, I always loved to go to S'pore.)
Please feel free to ask more questions.
Best wishes, Marcia