Traditional dosage: Two ombitasvir, paritaprevir, ritonavir 12.5/75/50 mg tablets once daily (in the morning) and one dasabuvir 250 mg tablet twice daily (morning and evening) with food, for 12 weeks. For patients with HCV genotype 1a and cirrhosis, ribivarin should be added. (Viekira Pak combines a NS5A inhibitor, a NS3/4A protease inhibitor, and a non-nucleoside NS5B polymerase inhibitor.)
Drug interactions, precautions, & recommendations: Do not take with Uroxatral, Carbatrol, Epitol, Equetro, Tegretol, Sustiva, Atripla, Cafergot, Complera, Kaletra, Migergot, Ergomar, Ergostat, Edurant, Medihaler, Wigraine, Wigrettes, D.H.E. 45, Migranal, Ergotrate, Methergine, ethinyl estradiol-containing medicines, Lopid, Advicor, Altoprev, Mevacor, oral midazolam, Norvir-boosted Prezista, Sustiva, Dilantin, Phenytek, Luminal, Orap, Zocor, Vytorin, Simcor, Viagra, Cialis, St. John’s Wort, Halcion, Rifadin, Rifamate, Rifater, Rimactane, or Revatio when taken for pulmonary artery hypertension. Do not take if you have liver cirrhosis or have had a severe skin rash after taking ritonavir (Norvir). Use with caution if you have other liver problems or have had a liver transplant and take the medicines Prograf, Gengraf, Neoral, or Sandimmune. If taken with ribavirin (brand names Copegus, Rebetol), all ribavirin warnings and contraindications apply.
The Federal Drug Administration issued the following label warning to be added to all hepatitis C (HCV) direct-acting antivirals (DAAs): Risk of hepatitis B virus (HBV) reactivation in patients connected with HCV and HBV has been reported, in some cases resulting in fulminant hepatitis, hepatic failure, and death.
Side effects: Most serious: liver damage or liver failure, hypersensitivity Other: nausea, itching, sleep problems