Efavirenz: What It Is, How It Works, and What You Need to Know

When you’re managing HIV, Efavirenz, a non-nucleoside reverse transcriptase inhibitor (NNRTI) used to block HIV replication. Also known as Sustiva, it’s one of the most commonly prescribed drugs in first-line HIV treatment regimens. Unlike some medications that attack the virus after it’s inside cells, Efavirenz stops HIV from making copies of itself right at the start—by targeting an enzyme the virus needs to replicate. This makes it a critical piece in keeping viral load low and immune function strong.

It doesn’t work alone. Efavirenz is always paired with other antiretroviral drugs like tenofovir or emtricitabine. That’s because HIV mutates fast, and using just one drug invites resistance. Together, these combinations can reduce viral load to undetectable levels, which means the virus can’t be passed on sexually. This isn’t just medical jargon—it’s life-changing. People on effective regimens live long, healthy lives, work, travel, and raise families without fear of transmission.

But Efavirenz isn’t for everyone. Some people experience side effects like dizziness, vivid dreams, or mood changes, especially in the first few weeks. These often fade, but if they stick around, your doctor might switch you to another NNRTI like rilpivirine or a different class altogether. It’s also not recommended during early pregnancy due to potential risks to the fetus. If you’re thinking about getting pregnant or are already pregnant, talk to your provider before starting or continuing Efavirenz.

It’s also important to take it on an empty stomach—ideally at bedtime—to reduce nausea and improve absorption. Missing doses can lead to drug resistance, which limits your future treatment options. That’s why many people use pill organizers or phone reminders. Consistency matters more than perfection.

What you’ll find in the posts below is a collection of real-world experiences and clinical insights about Efavirenz and similar HIV medications. You’ll see how people manage side effects, what alternatives exist when Efavirenz doesn’t fit, and how it fits into broader treatment plans alongside drugs like tenofovir, raltegravir, or dolutegravir. There’s no fluff—just clear, practical info from people who’ve been there, and the science that backs it up.