PrEP is not commonly associated with hair loss. Hair thinning does not appear on the official list of frequent side effects for either FDA-approved oral PrEP medication, and large clinical trials involving thousands of participants did not flag it as occurring in 2% or more of users. That said, a small number of people have reported hair loss after starting PrEP or switching between PrEP-related drugs, and a handful of case reports in the medical literature suggest a possible link worth understanding.
What the Clinical Trials Show
The DISCOVER trial, which compared the two oral PrEP options (Truvada and Descovy) in nearly 5,400 HIV-negative participants, tracked adverse reactions carefully. The most common side effects were diarrhea (5-6%), nausea (4-5%), headache (2%), fatigue (2-3%), and abdominal pain (2-3%). Hair loss was not listed among them for either drug. Most of these side effects are mild and tend to resolve within the first few weeks of use.
This doesn’t mean hair loss is impossible. Clinical trials report reactions that cross a statistical threshold, typically 2% of participants. A side effect that affects a smaller number of people can still be real for the individuals experiencing it, but it wouldn’t show up in the trial’s summary tables.
Case Reports Linking PrEP Drugs to Hair Loss
The strongest published evidence comes from a case series in Open Forum Infectious Diseases describing six African American women, ages 40 to 61, who developed hair loss after switching to a regimen containing tenofovir alafenamide (TAF), the same form of tenofovir found in Descovy. Hair loss was focal and confined to the scalp, appearing between 2 months and 1 year after the switch, though four of the six women noticed it within 2 to 4 months. None of them had pain, tenderness, scarring, or flaking around the affected areas.
When five of the six women were switched off the TAF-containing regimen, hair regrowth became noticeable within 1 to 5 months. The one woman who stayed on the medication and tried other hair restoration methods saw no improvement at 6 or 12 months. Using a standard scale for judging whether a drug caused a reaction, the researchers rated the connection between TAF and hair loss as “possible” rather than “probable” or “definite.”
A separate case report published in the International Journal of STD & AIDS documented hair loss in a patient taking a combination that included tenofovir disoproxyl fumarate (TDF), the form of tenofovir in Truvada. The authors noted that the biological mechanism behind the hair loss is currently unknown, and they could not pinpoint which drug in the combination was responsible.
Why It’s Hard to Pin Down
Hair loss has dozens of potential causes, which makes connecting it to any single medication tricky. The hair growth cycle itself complicates things: a disruption today might not produce visible thinning for weeks or months, making it hard to link cause and effect. Several factors common among PrEP users can independently trigger or worsen hair loss.
- Stress and lifestyle changes. Starting a new medication often coincides with other life changes, anxiety, or shifts in routine that can push hair follicles into a shedding phase.
- Other medications. People taking PrEP may also use other drugs that are known to affect hair, including certain antidepressants, hormonal treatments, or supplements.
- Age and genetics. Pattern hair loss becomes more common with age and can start or accelerate around the same time someone begins PrEP, creating a false association.
- Sexually transmitted infections. Secondary syphilis, which PrEP does not prevent, can cause a distinctive “moth-eaten” pattern of patchy, non-scarring hair loss on the scalp. These small, irregular patches of thinning hair typically appear on the back of the head and are not completely bald. Because PrEP users are regularly screened for STIs, this is usually caught, but it’s worth flagging if you notice patchy hair loss along with other symptoms.
Which PrEP Formulation Matters
There are currently three FDA-approved PrEP options: Truvada (containing TDF), Descovy (containing TAF), and Apretude (a long-acting injectable called cabotegravir). The published case reports of hair loss involve both TDF and TAF, so neither oral option is clearly “safer” for hair. The existing evidence is too limited to say whether one carries a meaningfully higher risk than the other.
Descovy’s FDA label does not list hair loss as a postmarketing adverse event, though it does list skin reactions like rash and hives. The absence of hair loss from the label reflects the rarity of reports rather than proof that it cannot happen.
What to Do if You Notice Thinning
If your hair starts thinning after beginning PrEP, the first step is paying attention to the timeline. Hair loss that begins within a few months of starting or switching PrEP medications is more suggestive of a drug connection than thinning that was already underway. Take note of whether the loss is diffuse (all over) or patchy, and whether it’s accompanied by any scalp symptoms like itching or tenderness. These details help a clinician narrow the cause.
Stopping PrEP on your own is not a good trade-off. The case reports suggest that when hair loss is drug-related, switching to a different PrEP formulation or a different antiretroviral backbone can allow regrowth, sometimes within a few months. A healthcare provider can help you weigh options without sacrificing HIV protection. In the case series of six women, those who switched medications saw improvement, while the one who stayed on the same drug did not.
Standard hair loss treatments like topical minoxidil, dietary changes to ensure adequate protein intake, and scalp massage may help support regrowth alongside any medication adjustments. These are reasonable to try while working with your provider on the underlying cause.
The Bottom Line on Risk
For the vast majority of people, PrEP does not cause hair loss. It is not listed among the common or even uncommon side effects in large clinical trials. But a small number of case reports, particularly involving TAF-containing regimens in certain populations, suggest it can happen in rare instances. The mechanism is unknown, and causality has not been firmly established. If you’re experiencing it, the pattern is potentially reversible once the medication is changed.