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Antivirals: Complete Pronunciation Guide

Antiviral drugs span six major mechanistic classes — antiherpes nucleoside analogs, HIV antiretrovirals, hepatitis C direct-acting antivirals, influenza neuraminidase inhibitors, CMV antivirals, and COVID-19 treatments. Each class carries INN suffixes that signal mechanism: -ciclovir (nucleoside analogs), -navir (protease inhibitors), -tegravir (integrase inhibitors), -asvir (NS5A inhibitors), -previr (NS3 protease inhibitors), -amivir (neuraminidase inhibitors). Mastering these patterns makes any unfamiliar antiviral pronounceable on first encounter.

Antiherpes Agents (Nucleoside Analogs)

Nucleoside analogs that are selectively phosphorylated by viral thymidine kinase. Used for HSV-1, HSV-2, VZV, EBV, and CMV infections. The -ciclovir stem identifies this class.

Acyclovir
ay-SYE-kloe-vir
Zovirax
Prototype antiherpes agent. IV, oral, topical. HSV-1, HSV-2, VZV. 5×/day oral dosing.
Valacyclovir
val-ay-SYE-kloe-vir
Valtrex
Prodrug of acyclovir. Superior bioavailability. Less frequent dosing (3×/day for zoster). HSV, VZV.
Famciclovir
fam-SYE-kloe-vir
Famvir
Oral prodrug of penciclovir. Zoster, genital HSV, orolabial HSV. 3×/day for 7 days (zoster).
Ganciclovir
gan-SYE-kloe-vir
Cytovene
IV/oral. CMV retinitis, CMV disease in immunocompromised. Myelosuppressive — limits use vs. letermovir.
Valganciclovir
val-gan-SYE-kloe-vir
Valcyte
Oral prodrug of ganciclovir. CMV prevention and treatment. Near-IV bioavailability. High myelotoxicity risk.
Cidofovir
si-DOF-oh-vir
Vistide
Acyclic nucleoside phosphonate. CMV retinitis in AIDS. Once-weekly dosing. Significant nephrotoxicity.
Foscarnet
fos-KAR-net
Foscavir
Pyrophosphate analog. CMV, HSV/VZV resistant to acyclovir. IV only. Nephrotoxic, electrolyte disturbances.
Letermovir
le-TER-moe-vir
Prevymis
CMV terminase inhibitor. Prophylaxis in allo-HSCT recipients. No myelosuppression. Novel mechanism.

Influenza Antivirals

Neuraminidase inhibitors (suffix -amivir) prevent viral release from infected cells. Baloxavir targets cap-dependent endonuclease (CEN), a distinct mechanism.

Oseltamivir
os-el-TAM-i-vir
Tamiflu
Oral neuraminidase inhibitor. Influenza A and B treatment (within 48h of symptoms) and prophylaxis.
Zanamivir
za-NAM-i-vir
Relenza
Inhaled neuraminidase inhibitor. Influenza A and B. Disc inhaler device. Contraindicated with bronchospasm.
Baloxavir
ba-LOX-a-vir
Xofluza
Cap-dependent endonuclease inhibitor. Single-dose oral treatment for influenza A and B. Novel mechanism.

COVID-19 Antivirals

Treatments for SARS-CoV-2 targeting viral polymerase (remdesivir, molnupiravir) or main protease (nirmatrelvir).

Nirmatrelvir
nir-MA-trel-vir
Paxlovid (with ritonavir)
SARS-CoV-2 main protease inhibitor. Oral, 5-day course. Started within 5 days of symptom onset. Significant drug interactions.
Remdesivir
rem-DES-i-vir
Veklury
Nucleoside analog RNA polymerase inhibitor. IV (3 or 5 days). COVID-19 in hospitalized patients requiring oxygen.
Molnupiravir
mol-NOO-pir-a-vir
Lagevrio
Nucleoside analog prodrug causing viral error catastrophe. Oral, 5-day course. Second-line after nirmatrelvir contraindicated.

HIV Antiretrovirals

Combination antiretroviral therapy (ART) suppresses HIV viral load to undetectable. Key classes: NRTIs (-vudine, -abine), NNRTIs (-virine/-avir), protease inhibitors (-navir), and integrase inhibitors (-tegravir).

Dolutegravir
doe-loo-TEG-ra-vir
Tivicay • Triumeq (combo)
Second-generation integrase inhibitor. High barrier to resistance. Preferred backbone in most first-line regimens.
Bictegravir
bik-TEG-ra-vir
Biktarvy (BIC/TAF/FTC)
Integrase strand transfer inhibitor. Only available in fixed-dose combination Biktarvy. High resistance barrier.
Tenofovir
te-NOF-oh-vir
Viread (TDF) • Vemlidy (TAF)
NRTI backbone in most HIV regimens. Also active against HBV. TAF has less bone/renal toxicity than TDF.
Emtricitabine
em-trye-SIT-a-been
Emtriva • Truvada (combo)
Cytidine NRTI. Paired with tenofovir in most first-line regimens. Also active against HBV.
Efavirenz
e-FAV-i-renz
Sustiva • Atripla (combo)
NNRTI. Once-daily. CNS side effects (vivid dreams, dizziness) common early. CYP3A inducer.
Darunavir
da-ROO-na-vir
Prezista • Prezcobix
Preferred HIV protease inhibitor. Boosted with ritonavir or cobicistat. High genetic barrier to resistance.
Lopinavir
loe-PIN-a-vir
Kaletra (with ritonavir)
Protease inhibitor always co-formulated with ritonavir. WHO second-line in resource-limited settings.
Atazanavir
at-a-ZAN-a-vir
Reyataz
HIV protease inhibitor. Once daily, ritonavir or cobicistat boosted. Characteristic: indirect hyperbilirubinemia.
Abacavir
a-BAK-a-vir
Ziagen • Epzicom • Triumeq
NRTI. Requires HLA-B*5701 screening to avoid hypersensitivity reaction. Cardiovascular risk signal in some data.
Zidovudine
zye-DOE-vyoo-deen
Retrovir (AZT)
First approved HIV drug (1987). NRTI. Used in maternal-neonatal HIV prevention. Myelosuppression limits use.
Lamivudine
la-MIV-yoo-deen
Epivir (3TC)
Cytidine NRTI. Active against HIV and HBV. Component of many fixed-dose combination tablets globally.
Raltegravir
ral-TEG-ra-vir
Isentress
First-generation integrase inhibitor. Twice-daily (or HD once-daily). Lower resistance barrier vs. dolutegravir.
Elvitegravir
el-vi-TEG-ra-vir
Stribild • Genvoya
Integrase inhibitor, always in fixed-dose combination (with cobicistat booster). First-generation; lower resistance barrier.
Nevirapine
ne-VYE-ra-peen
Viramune
NNRTI. Used in resource-limited settings and for PMTCT. Hepatotoxicity and rash risk; avoid in high CD4 patients.
Ritonavir
ri-TOE-na-vir
Norvir • Kaletra (combo)
HIV protease inhibitor and pharmacokinetic booster (CYP3A inhibitor). Low-dose ritonavir boosts darunavir, lopinavir, nirmatrelvir.

Hepatitis C Direct-Acting Antivirals (DAAs)

Direct-acting antivirals (DAAs) target three HCV proteins: NS3/4A protease (-previr), NS5A replication complex (-asvir), and NS5B polymerase (-buvir). Combination therapy achieves >95% cure rates.

Sofosbuvir
soe-FOS-byoo-vir
Sovaldi • Harvoni (combo) • Epclusa (combo)
NS5B nucleotide polymerase inhibitor. Backbone of most HCV regimens. Pangenotypic. Approved 2013.
Ledipasvir
le-DIP-as-vir
Harvoni (with sofosbuvir)
NS5A inhibitor. Combined with sofosbuvir. HCV genotypes 1, 4, 5, 6. 8–12 week treatment.
Velpatasvir
vel-PAT-as-vir
Epclusa (with sofosbuvir)
Pangenotypic NS5A inhibitor. Sofosbuvir/velpatasvir (Epclusa) treats all HCV genotypes 1–6 in 12 weeks.
Glecaprevir
glek-a-PREV-ir
Mavyret (with pibrentasvir)
NS3/4A protease inhibitor. Pangenotypic. With pibrentasvir: 8 weeks for treatment-naive, renal-safe.
Pibrentasvir
pie-BREN-tas-vir
Mavyret (with glecaprevir)
NS5A inhibitor. Pangenotypic. Combined with glecaprevir in Mavyret. SVR12 >97% in 8 weeks.
Ribavirin
rye-ba-VYE-rin
Copegus • Virazole
Nucleoside analog. Previously essential with interferon-based HCV therapy. Now only used in select difficult-to-treat genotypes.

Antiviral INN Suffix Guide

International Nonproprietary Names (INN) use systematic suffixes to identify antiviral drug classes. Learning these patterns lets you identify any antiviral’s class on first encounter.

-ciclovir

Antiherpes nucleoside analogs: acyclovir, valacyclovir, famciclovir, ganciclovir, valganciclovir

-navir

HIV protease inhibitors: ritonavir, lopinavir, darunavir, atazanavir, nirmatrelvir (also a protease inhibitor)

-tegravir

HIV integrase strand transfer inhibitors: raltegravir, elvitegravir, dolutegravir, bictegravir

-asvir

HCV NS5A inhibitors: ledipasvir, velpatasvir, pibrentasvir, daclatasvir

-previr

HCV NS3/4A protease inhibitors: glecaprevir, simeprevir, boceprevir, telaprevir

-amivir

Influenza neuraminidase inhibitors: oseltamivir, zanamivir, peramivir

-vudine

Thymidine NRTIs: zidovudine, stavudine, lamivudine (cytidine analog but uses -vudine)

-fovir

Acyclic nucleoside phosphonates: tenofovir, cidofovir, adefovir