What to Do if You Missed Multiple Doses
Missing several doses in a row or many doses within a relatively short period of time is a different matter. If this occurs, contact your HIV provider promptly for guidance — rather than waiting for your next appointment.
Repeated missed doses can give HIV room to start replicating again, leading to a “viral rebound” where your viral load rises to detectable levels. It can also increase the chance that the virus will become resistant to your current medication and stop working effectively, limiting your treatment options.
Drug resistance is most likely to occur if you’re on an older class of HIV medications called non-nucleoside reverse transcriptase inhibitors or, to a lesser degree, nucleoside reverse transcriptase inhibitors.
Modern ART in the integrase inhibitor and protease inhibitor classes generally have a higher barrier to drug resistance and viral rebound.
Still, even the newer drugs aren’t immune to resistance in people with irregular adherence. A report published by the World Health Organization in 2024 noted that dolutegravir, a common integrase inhibitor, was associated with drug resistance at higher rates than expected from clinical trials.
But “they really do give a lot of protection and offer forgiveness,” Blumenthal says, adding that research suggests you have to have an adherence rate of about 80 to 85 percent to maintain viral suppression with modern ART.
“When you’re missing 15 percent or more of your doses, you’re starting to reach a more critical place,” she says.
Every person is different, however, and it’s important for people with HIV to take their medication every day and know their viral load if they’re missing multiple doses, Dr. Chow says. “If they’re clearly symptomatic — if they feel like a flu-like illness is coming on — we’d be more concerned about getting them in and testing them,” he says. “If they’re someone who’s been virologically suppressed for months on end, the concern isn’t as high, but they should still be tested just to make sure they remain virologically suppressed.”
