The drugs of choice for treatment of viral infections (other than HIV) and their dosages are listed in Tables 1-6 on the pages that follow. Some of the indications and dosages recommended here have not been approved by the FDA. Vaccines used for the prevention of viral infections are discussed elsewhere.

Atazanavir (Reyataz - Bristol-Myers Squibb), a new protease inhibitor (PI), and emtricitabine (Emtriva - Gilead), a nucleoside analogue reverse transcriptase inhibitor (NRTI) chemically similar to lamivudine, have been approved by the FDA for treatment of HIV-1 infection. Both are taken once daily, unlike most anti-HIV drugs.

The FDA has approved a fixed-dose combination (Harvoni [har voe' nee] – Gilead) of sofosbuvir and ledipasvir (led' i pas' vir), two oral direct-acting antiviral agents, for treatment of chronic hepatitis C virus (HCV) genotype 1 infection. Genotype 1 is responsible for 70-80% of HCV infections in the US. Sofosbuvir (Sovaldi) was approved earlier for use in combination with other antiviral drugs for treatment of HCV infection. Ledipasvir is a new drug.

The FDA has approved Mavyret (Abbvie) and Vosevi (Gilead), two new fixed-dose combinations of direct-acting antiviral (DAA) drugs, for treatment of chronic hepatitis C virus (HCV) infection caused by any of the six major HCV genotypes in patients without cirrhosis or with compensated cirrhosis. Both are approved for use in treatment-experienced patients. Mavyret is also approved for treatment-naive patients.

The recommendations for treatment of varicella-zoster virus (VZV) and herpes simplex virus (HSV) infections are listed in tables 1 and 2. Vaccination against VZV was reviewed in a previous issue.

Darunavir (Prezista - Tibotec), a new protease inhibitor, has received accelerated approval from the FDA for use in combination therapy of human-immunodeficiency virus (HIV) infection in previously treated adults. It is coadministered with low-dose ritonavir (Norvir), which increases its bioavailability.

About 2.5 million persons in the US had hepatitis C between 2017 and 2020. Guidelines from the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) on management of hepatitis C virus (HCV) infection were updated in 2023.

The FDA has approved Epclusa (Gilead), a fixed-dose combination of sofosbuvir (Sovaldi) and velpatasvir, a new direct-acting antiviral agent, for oral treatment of chronic hepatitis C virus (HCV) infection. Epclusa is the first oral combination to be approved for treatment of all six major HCV genotypes.

Raltegravir (Isentress - Merck), the first in a new class of oral HIV drugs called HIV-1 integrase strand transfer inhibitors (InSTI), has received accelerated FDA approval for use in combination therapy for treatment-experienced adults infected with HIV-1 strains resistant to multiple antiretroviral agents.

Maraviroc (Selzentry - Pfizer), the first CCR5 (CC chemokine receptor 5) antagonist has received the same FDA approval but is restricted to use in adults with CCR5-tropic HIV-1 ("R5 virus"). A commercial assay is available for R5 tropism.