R R

What Is a Reverse Transcriptase Inhibitor?

A reverse transcriptase inhibitor is an antiviral medicine that blocks an enzyme used by certain viruses to copy ribonucleic acid into deoxyribonucleic acid. Human immunodeficiency virus requires reverse transcriptase early in its replication cycle. The main HIV drug groups are nucleoside or nucleotide reverse transcriptase inhibitors and non-nucleoside reverse transcriptase inhibitors. Several nucleoside or nucleotide analogs also suppress hepatitis B virus polymerase activity.

Link to This Resource Page

Provide a valuable resource to your clients or customers by linking to this resource page. Just place the following link on your website.

To display this...

What Is a Reverse Transcriptase Inhibitor?

A reverse transcriptase inhibitor is an antiviral medicine that blocks an enzyme used by certain viruses to copy ribonucleic acid into deoxyribonucleic acid. Human immunodeficiency virus requires reverse transcriptase early in its replication cycle. The main HIV drug groups are nucleoside or nucleotide reverse transcriptase inhibitors and non-nucleoside reverse transcriptase inhibitors. Several nucleoside or nucleotide analogs also suppress hepatitis B virus polymerase activity.

read more about reverse transcriptase inhibitor ...

Copy this HTML:

Copy HTML Copied!

What Are Reverse Transcriptase Inhibitors Used For?

Reverse transcriptase inhibitors are core components of combination antiretroviral therapy for human immunodeficiency virus. Selected agents are also used for preexposure or postexposure prophylaxis against HIV when included in recommended regimens. Tenofovir, entecavir, lamivudine, and selected related medicines have roles in chronic hepatitis B treatment. The same drug can have different doses, combinations, or resistance considerations for different viruses.

How Do Reverse Transcriptase Inhibitors Work?

Nucleoside and nucleotide reverse transcriptase inhibitors resemble natural building blocks used to make viral DNA. After intracellular activation, they compete for incorporation and commonly terminate or disrupt the growing DNA chain. Non-nucleoside inhibitors bind to a separate site on HIV-1 reverse transcriptase and change the enzyme's shape or function. These drugs prevent productive viral replication but do not remove integrated HIV DNA from infected cells.

What Types of Reverse Transcriptase Inhibitors Are There?

Nucleoside reverse transcriptase inhibitors include abacavir, emtricitabine, lamivudine, and zidovudine. Nucleotide analogs include tenofovir disoproxil fumarate and tenofovir alafenamide. Non-nucleoside reverse transcriptase inhibitors include doravirine, efavirenz, etravirine, nevirapine, and rilpivirine. Drugs within each group differ in resistance barrier, interactions, organ toxicity, formulation, and viral activity.

What Are the Side Effects and Resistance Concerns?

Side effects vary by drug and can include nausea, rash, sleep or mood effects, liver injury, kidney injury, bone effects, blood-cell changes, or metabolic complications. Abacavir can cause a serious hypersensitivity reaction in patients with the HLA-B*57:01 allele. Missed doses or incomplete regimens can allow viral mutations that reduce drug activity and limit future options. Treatment requires adherence, interaction review, viral-load monitoring, and product-specific laboratory testing.

Frequently Asked Questions About Reverse Transcriptase Inhibitors

Are reverse transcriptase inhibitors used alone for HIV?

No. HIV treatment uses a combination regimen containing medicines from at least two drug classes to improve suppression and reduce resistance.

What is the difference between an NRTI and an NNRTI?

An NRTI or nucleotide analog mimics a DNA building block, while an NNRTI binds directly to a separate site on HIV-1 reverse transcriptase.

Do reverse transcriptase inhibitors cure HIV?

No. They suppress viral replication and help protect immune function, but they do not remove the persistent viral reservoir.

Can hepatitis B worsen after stopping certain inhibitors?

Yes. Stopping medicines active against hepatitis B can cause a severe flare. Discontinuation requires medical supervision and liver monitoring.

References

Nucleoside Reverse Transcriptase Inhibitor (NRTI). National Institutes of Health ClinicalInfo. https://clinicalinfo.hiv.gov/en/glossary/nucleoside-reverse-transcriptase-inhibitor-nrti. Date Accessed August 6, 2026.

Non-Nucleoside Reverse Transcriptase Inhibitor (NNRTI). National Institutes of Health ClinicalInfo. https://clinicalinfo.hiv.gov/en/glossary/non-nucleoside-reverse-transcriptase-inhibitor-nnrti. Date Accessed August 6, 2026.

What to Start: Initial Combination Antiretroviral Regimens. National Institutes of Health ClinicalInfo. https://clinicalinfo.hiv.gov/en/guidelines/hiv-clinical-guidelines-adult-and-adolescent-arv/what-start-initial-combination-regimens. Date Accessed August 6, 2026.

Laboratory Testing: HLA-B*5701 Screening. National Institutes of Health ClinicalInfo. https://clinicalinfo.hiv.gov/en/guidelines/hiv-clinical-guidelines-adult-and-adolescent-arv/hla-b-5701-screening. Date Accessed August 6, 2026.

VEMLIDY (Tenofovir Alafenamide) Tablets: Prescribing Information. DailyMed. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=72e6b33c-0351-4070-9172-eeaa186c01d2. Date Accessed August 6, 2026.