Hello JohnSmith,
The instructions are correct and can be checked here:
www.drugs.com/dosage/viekira-pak.html
The recommended oral dosage of VIEKIRA PAK is two ombitasvir, paritaprevir, ritonavir tablets once daily (in the morning) and one dasabuvir tablet twice daily (morning and evening). Take VIEKIRA PAK with a meal without regard to fat or calorie content.
The logic is:
a) The PrO part (Paritaprevir, ritonavir, Ombbitasvir) is metabolised slowly enough that once daily dosing works
b) The Dasabuvir gets metabolised (chewed up) fast so you need it twice a day to keep the levels up
c) Ribavirin as a single 1000mg dose is harsh so even though it is metabolised slowly we split the dose to soften the blow...
Can I have a heart attack since I'm 36 years old with a BMI of 42?
Probably not, but a BMI of 42 is not doing you any favors. I have attached my eBook on Weight Loss which contains every bit of good diet advice there is (without the marketing BS). I was a fat kid (nickname tank to start with, then piggy) so have a special interest in weight.
Mostly people do fine on standard dosing, but as a big lad you're right that giving you more than a 5'0 girl would make sense. That said the evidence is that the drugs work for pretty much everyone. If you wanted insurance adding Sofosbuvir (generic) is safe and would push your cure rate to so close to 100% that you could almost call it a sure thing. That said you really don't need to. If you're unfortunate enough to be in the ~ 3% of people who fail we have plenty of salvage options. So you would have a 97% chance of wasting money to cover a 3% risk.
Doses should be as close to the same time as practical but don't sweat a couple of hours either way each day. It ain't gonna matter.