With the rise of PrEP (Pre-Exposure Prophylaxis) as a game-changing tool in HIV prevention, many people are asking new and important questions like: “If someone is on PrEP, can they still give you HIV?”
It’s a smart question. Understanding how PrEP works, what it protects against, and what it doesn’t is essential to making informed decisions about your health and relationships.
The short answer is: If someone is truly taking PrEP consistently and correctly, they are extremely unlikely to acquire HIV and therefore, are also very unlikely to transmit it.
But there’s nuance to that. In this article, we’ll cover:
- How PrEP works?
- What “undetectable = untransmittable” means
- Whether someone on PrEP can still have HIV
- How to protect yourself fully with HIV testing services and prevention?
- Why it’s still smart to test regularly even if your partner is on PrEP
- How MISTR can help you stay HIV-negative for free
Key Takeaways
- You can’t get HIV from someone who is HIV-negative and consistently on PrEP.
- PrEP is 99% effective when taken daily making transmission extremely unlikely.
- Risk increases only if someone stops PrEP, misses doses, or acquires HIV unknowingly.
- It’s still important to get tested regularly and manage your own prevention plan.
- MISTR offers anonymous HIV testing, free at-home kits, and daily PrEP prescriptions all online and at no cost for most users.
- HIV prevention works best when both partners are informed, tested, and protected.
What Is PrEP and How Does It Work?
PrEP (Pre-Exposure Prophylaxis) is a once-daily medication that helps HIV-negative individuals prevent HIV infection if they are exposed to the virus. If you’re new to PrEP, you can read our full guide on how PrEP works to understand the science behind it.
PrEP works by:
- Building up antiviral medication in your bloodstream
- Blocking HIV from replicating if it enters your body
- Reducing the risk of HIV by 99% when taken daily
There are currently two FDA-approved oral PrEP options:
- Truvada® (or its generics)
- Descovy® (for select populations)
You can access both through MISTR, with:
- Anonymous HIV testing
- Online consultations
- Discreet medication delivery
- $0 cost for most users
So… Can Someone on PrEP Still Give You HIV?
If your sexual partner is on PrEP and takes it correctly, they are very unlikely to become HIV-positive which means they can’t pass the virus to you.
Here’s the logic:
- PrEP is for HIV-negative people.
- It helps them stay negative, even if exposed.
- If they’re HIV-negative, they can’t transmit HIV because they don’t have it.
So if someone is:
- On PrEP
- Taking it every day
- Regularly testing negative for HIV
They are not a source of HIV transmission.
What If They’re Not Taking It Properly?
Here’s where the risk could come in.
Risk exists if:
- They miss multiple doses of the daily prep pill
- They stopped PrEP without telling their partner
- They acquired HIV but didn’t know it, and are no longer protected
- They never completed routine HIV testing services
PrEP is extremely effective, but only if taken correctly and consistently. That’s why regular testing every 3 months is part of all responsible PrEP programs including the one offered by MISTR.
What If Someone on PrEP Does Get HIV?
Although rare, it is possible, especially if:
- Someone had drug-resistant HIV exposure
- They weren’t taking PrEP daily
- There was a long delay between infection and testing
In rare cases, a person on PrEP can become HIV-positive and not know it right away. If they’re still sexually active, transmission is theoretically possible but extremely rare.
That’s why routine HIV testing services are built into every PrEP care plan.
How Does This Differ from Someone Who Is HIV-Positive on Treatment?
Here’s another angle people often confuse: Someone who is HIV-positive and on treatment is not the same as someone who is HIV-negative and taking PrEP.
HIV-positive individuals can reach a point where the virus is undetectable in their blood. This is called:
“Undetectable = Untransmittable” (U=U)
It means:
- Their HIV viral load is so low it can’t be passed through sex
- They must be on ART (antiretroviral therapy) consistently
- They are not contagious even though they’re HIV-positive
This is different from PrEP, which is taken by HIV-negative people to prevent infection.
Both approaches are effective at stopping HIV transmission but they apply to different situations.
How to Stay Protected No Matter Your Partner’s Status?
Even if your partner is on PrEP or undetectable, it’s smart to:
- Get tested regularly
- Know your own HIV and STI status
- Take PrEP yourself if you’re at risk
- Use condoms as an added layer of protection
Think of sexual health as a team effort, you both deserve peace of mind.
Should You Still Get Tested if Your Partner Is on PrEP?
Yes—100%.
Here’s why:
- PrEP doesn’t prevent STIs like gonorrhea, chlamydia, or syphilis
- Your partner could miss doses or stop PrEP
- You deserve your own baseline health info
- Testing is free and easy through MISTR
Testing is part of responsible sexual health, not a sign of distrust.
How MISTR Makes Testing and PrEP Simple?
MISTR offers:
- Free HIV and STD testing kits shipped to your door
- Anonymous HIV testing with fast results
- No clinic visits or awkward conversations
- Online consults with licensed LGBTQ+ providers
- Daily prep pill prescriptions shipped monthly
- Doxy prep pill (DoxyPEP) to help prevent STIs
Most users pay $0 out of pocket and the whole process is judgment-free.
Final Thoughts
If your partner is on PrEP, that’s a good thing and it means they care about their health and yours. When taken properly, PrEP makes HIV transmission nearly impossible. But no prevention plan is complete without routine testing, open communication, and, when needed, your own prescription for PrEP or DoxyPEP.
With MISTR, getting started is easy:
- No doctor’s office
- No lab visits
- No judgment
Just fast, discreet, expert care designed for real people with real lives.