Can PrEP Drugs Interact with Gender-Affirming Hormone Therapy?
Key takeaways:
Pre-exposure prophylaxis (PrEP) is an HIV prevention technique that’s a good option for people at risk for HIV infection. This includes those taking gender-affirming hormone therapy (GAHT).
Current evidence suggests that PrEP medications don’t appear to affect GAHT medication levels.
Some estrogen-based GAHT can lead to lower levels of tenofovir, a commonly used PrEP medication. But they’re still safe to take at the same time.
Table of contents
Pre-exposure prophylaxis (PrEP) is one of the best ways to prevent HIV infection. Current PrEP medication options include Truvada (emtricitabine/tenofovir disoproxil fumarate), Descovy (emtricitabine/tenofovir alafenamide), and Apretude (cabotegravir).
PrEP medications can prevent HIV in people at risk for an HIV infection. When used as directed, they lower the risk of getting HIV from sex by about 99%.
Certain people who can benefit from PrEP might also be taking gender-affirming hormone therapy (GAHT). And there may be a concern that these two treatments can interact. This may cause hesitation about taking PrEP consistently — or at all. There may also be doubts as to whether PrEP is still effective when taken with GAHT.
Let’s unpack what the research says about potential interactions between GAHT and PrEP, and what it could mean for you.
How does pre-exposure prophylaxis (PrEP) work?
Antiretrovirals (ARVs) — medications that work against HIV — are used for PrEP. But, when taken alone, Truvada, Descovy, and Apretude aren’t enough to treat HIV; they can only prevent it.
When it comes to HIV treatment, healthcare providers prescribe a combination of ARVs to lower the amount of virus in the body. A complete HIV regimen usually contains two or more ARVs from at least two different ARV medication classes. Using medications that attack the virus with different mechanisms prevents HIV from becoming resistant to medication.
Apretude is an injection that only contains one ARV. Truvada and Descovy are oral tablets that contain two ARVs, but they’re from the same medication class. Therefore, none of these options are full HIV regimens. But, they are very good at preventing infection in people who don’t have HIV.
When you take PrEP medications, your body builds up an ARV medication storage. So, these medications are ready to fight the virus as soon as you’re exposed to it. This fast action prevents HIV from infecting your immune cells and making copies of itself.
Who is recommended to take PrEP?
Simply put, PrEP is a good option for anyone who doesn’t currently have HIV and feels at risk of acquiring an HIV infection through sex or injection drug use.
The CDC and the 2021 PrEP guidelines provide the following guidance on who might be good candidates for PrEP:
People who inject drugs and share injection equipment
Sexually active people with a sexual partner who has HIV (especially if they’re not on treatment, or they have a detectable amount of virus)
Sexually active people who don’t always use condoms
People who’ve had a recent STI (in the last 6 months)
Anyone who has been prescribed post-exposure prophylaxis (PEP)
If you aren’t sure if PrEP is right for you, talk to your healthcare provider.
Do PrEP drugs affect gender-affirming hormone therapy?
GAHT is typically categorized as two types: testosterone-based or estrogen-based. Testosterone is the cornerstone of testosterone-based GAHT. Estrogen-based GAHT includes estrogen and/or testosterone blockers, like spironolactone (Aldactone), finasteride (Proscar), and dutasteride (Avodart).
Can PrEP drugs make gender-affirming hormone therapy less effective?
Truth be told, there’s a lot of room for research on this topic. There have been a few studies that have looked at potential interactions between oral PrEP medications (Truvada and Descovy) and GAHT. Currently, there’s no evidence that says Truvada or Descovy make GAHT less effective.
Apretude is a newer PrEP option, and there haven’t been any studies looking at how it affects GAHT. Currently, there aren’t any interactions expected between Apretude and GAHT.
Is it safe to combine PrEP with gender-affirming hormone therapy?
Yes. From what we know, it’s safe to take PrEP with GAHT.
There’s some evidence showing that estrogen-based GAHT medications, such as spironolactone and estrogen, may lead to lower tenofovir levels in transgender women. Scientists believe the tenofovir level reduction isn’t significant, and that Truvada once a day is still a good option for transgender women taking estrogen-based GAHT.
However, on-demand PrEP — a dosing schedule where you only take PrEP around the time of an at-risk event — isn’t recommended for transgender women taking estrogen-based GAHT at this time.
Can other HIV medications interact with gender-affirming hormone therapy?
Aside from PrEP medications, there are some other ARVs that may interact with GAHT. These medications are used to treat HIV, not prevent it. Below are a few examples.
| HIV medication(s) | Effects on GAHT levels in the body |
|---|---|
| Ritonavir (Norvir) Cobicistat (Tybost) |
Raises levels of dutasteride, finasteride, and testosterone |
| Ritonavir | Leads to lower levels of estradiol |
| Efavirenz (Sustiva) Etravirine (Intelence) Nevirapine (Viramune) |
Leads to lower levels of estradiol, dutasteride, finasteride, and testosterone |
Despite these interactions, you can take these HIV medications with GAHT. But your healthcare provider will need to monitor your medication levels closely, and adjust your dose as needed.
How can I access PrEP if I think I’m eligible to take it?
Anyone who thinks they’re a good candidate for PrEP should talk to a healthcare provider. A good place to start can be your primary care provider (PCP), or the person who prescribes your GAHT medications.
If you’re not currently connected to a healthcare provider, PleasePrEPMe has a list of telehealth providers that offer PrEP services. If you’d prefer to see a provider in-person, there are resources available to help you locate one. The National Prevention Information Network PrEP locator is one such example.
How much does PrEP cost?
The cost of PrEP will vary widely depending on the person and the medication. In most cases, the least expensive PrEP option is Truvada, which is available as a lower-cost generic medication.
Many insurance plans will cover Truvada, but you might be responsible for a copay. If it’s not covered, or if you don’t have insurance, you can find the generic version for less than $40 with a free GoodRx discount at certain pharmacies.
A similar medication is Descovy, another once-daily tablet. Descovy is a newer medication that’s only available as a brand-name medication. If it’s not covered by your insurance, it can be very expensive.
Lastly, Apretude is the newest PrEP option. It’s an ARV that’s injected once every 2 months. Apretude needs to be given by a healthcare professional at a medical facility, like a clinic. So, you typically won’t find this medication available at a pharmacy.
The bottom line
There’s more work to be done regarding medication interactions between PrEP and GAHT. But with the research we do have, experts believe that PrEP and GAHT can be taken together safely.
As always, take your medications as directed by your healthcare provider and have regularly scheduled follow-up visits. That way, if needed, they can order labs to make sure your medication levels are safe and effective.
Why trust our experts?
References
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