Veozah (Fezolinetant) for Hot Flashes: How It Works and Side Effects

Veozah (fezolinetant) is a once-daily, non-hormonal prescription pill that treats moderate-to-severe hot flashes and night sweats caused by menopause. Approved by the U.S. Food and Drug Administration in 2023, it is the first in a class of drugs called neurokinin 3 (NK3) receptor antagonists. Instead of replacing estrogen, it quiets an overactive brain circuit that drives hot flashes — which is why it has become an option for women who cannot or would rather not take hormones. It is prescription-only, clinician-managed, and comes with a liver-monitoring requirement.

What Veozah is and who it's for

Menopausal hot flashes and night sweats are together called vasomotor symptoms. For some women they are occasional and mild; for others they are frequent, drenching, and genuinely disruptive to sleep, work, and mood. Veozah is aimed squarely at the moderate-to-severe end of that spectrum.

It may be a particularly useful option if you:

• Have a personal history that makes estrogen inadvisable — for example, certain hormone-sensitive cancers, blood clots, or a history of stroke
• Prefer to avoid hormones for personal reasons
• Have tried hormone therapy and stopped it, or found it didn't suit you

Veozah is not a fertility treatment, a contraceptive, or a general "menopause pill." It targets hot flashes and night sweats specifically. It does not treat vaginal dryness, bone loss, or mood changes. If your main concern is something other than flashing, it may not be the right tool — see our overview of menopausal hot flashes and of non-hormonal menopause treatment options to compare.

How fezolinetant works: the KNDy pathway

To understand Veozah, it helps to know what actually causes a hot flash. Deep in the brain's hypothalamus sits a small cluster of nerve cells nicknamed KNDy neurons (after the signaling molecules they use: kisspeptin, neurokinin B, and dynorphin). These neurons sit right next to the body's thermostat — the region that decides when you're too hot and need to sweat and flush to cool down.

Estrogen normally keeps KNDy neurons in check. As estrogen falls during the menopause transition, these neurons grow larger and more active. The extra signaling — driven in part by neurokinin B binding to the NK3 receptor — effectively narrows the brain's comfortable temperature zone. Small shifts in body heat that you'd once ignore now trip the alarm, and the body launches a full cooling response: the sudden warmth, flush, and sweat of a hot flash.

Fezolinetant blocks the NK3 receptor. By stopping neurokinin B from over-stimulating those neurons, it helps restore a more normal balance in the temperature-control center — without adding any estrogen back into the body. That is the key distinction: hormone therapy works by replacing the missing estrogen, while fezolinetant works downstream, on the brain circuitry that estrogen loss disrupts.

How well does it work?

In the clinical trials that supported its approval, fezolinetant reduced both the frequency and severity of moderate-to-severe hot flashes compared with placebo, with improvements that generally appeared within the first few weeks and continued over the study period. Many participants also reported better sleep, which makes sense given how often night sweats fragment it.

Two honest caveats. First, "better" does not mean "gone" — most women see a meaningful drop in how many flashes they get and how intense they are, not a complete disappearance. Second, in head-to-head terms, systemic estrogen remains the most effective treatment for vasomotor symptoms. Fezolinetant is valuable precisely because it offers a genuinely effective non-hormonal route for people who need one. If it's going to help you, you'll usually have a sense within the first month or two; your clinician can reassess if it isn't.

Veozah vs. other approaches to hot flashes

Veozah is one of several routes. The table below sketches how it compares in broad strokes — not as a ranking, but to show where each option fits.

Which of these fits depends on your health history, other symptoms, and preferences — a conversation worth having with a clinician rather than settling from a chart.

Side effects and the liver-monitoring requirement

The most important thing to understand about Veozah is its liver safety profile. Fezolinetant can raise liver enzymes, a sign of liver stress, and the FDA has warned about a risk of rare but serious liver injury — a warning the agency strengthened after approval. Because of this, the labeling requires liver blood tests on a set schedule:

• A baseline blood test before you start, to confirm your liver is healthy enough
• Repeat blood tests on a defined schedule across roughly the first nine months of treatment — the FDA-approved labeling calls for testing before you begin and then periodic checks (more frequent early on, then at set intervals), following the exact timing your prescriber sets

This monitoring is not optional box-ticking — it is how a rare problem gets caught early. Just as importantly, you are part of the safety net. Contact your clinician promptly and stop the drug if you notice signs of liver trouble, such as:

• Yellowing of the skin or the whites of the eyes (jaundice)
• Dark or "tea-colored" urine
• Pain in the upper-right area of your abdomen
• Unusual fatigue, nausea, loss of appetite, or light-colored stools

Beyond the liver, the more commonly reported side effects in trials included abdominal pain, diarrhea, difficulty sleeping, and back pain. Most were on the milder side, but tell your clinician about anything that bothers you. Never adjust or exceed the labeled once-daily dose on your own.

Who should not take it

Fezolinetant is not appropriate for everyone. Per the FDA labeling, it should not be used by people who have:

• Known cirrhosis or other significant liver disease
• Severe kidney impairment or end-stage kidney disease
• A need for certain interacting medications — notably drugs that strongly block the CYP1A2 enzyme, which can raise fezolinetant levels in the body

This is exactly why an accurate medication list matters. Bring every prescription, over-the-counter product, and supplement you take to the appointment so your clinician can check for interactions before writing the prescription.

Practical questions to ask your clinician

If you're weighing Veozah, these questions can make the conversation more productive:

1. Given my health history, is a non-hormonal option like this a better fit than hormone therapy — or the other way around?
2. What will my liver-test schedule look like, and how will we handle a result that's off?
3. Do any of my current medications or supplements interact with it?
4. How soon should I expect to notice a difference, and when will we decide whether it's working?
5. What's the plan if the side effects outweigh the benefit?

The bottom line

Veozah (fezolinetant) filled a real gap: an effective, genuinely non-hormonal way to treat moderate-to-severe menopausal hot flashes by targeting the brain pathway that drives them, rather than by replacing estrogen. For women who can't or won't take hormones, that's meaningful. The trade-off is a real one — the drug carries a liver-injury risk and comes with a monitoring requirement you need to take seriously, along with clear rules about who shouldn't use it.

None of this is a decision to make from an article. Whether fezolinetant is right for you depends on your history, your other symptoms, and your own priorities — a conversation for you and a clinician who can order the baseline tests, check for interactions, and follow you over time. Use this guide to walk in informed, not to self-prescribe.