Vesper Science is a clinically-dosed daily supplement formulated for the peri-menopause transition. One formula. 21 symptoms addressed. Nine actives — each at the exact dose used in the published clinical trials that validated it. No proprietary blends. No under-dosing. No filler. Every ingredient and milligram is printed on the label.

Peri-menopause symptoms don’t appear in isolation — hot flashes disturb sleep, poor sleep raises cortisol, high cortisol worsens metabolism, metabolism shifts weight, weight shifts affect mood. Instead of chasing each symptom with a separate product, Vesper targets the underlying hormonal transition with nine actives that, between them, modulate the full downstream cascade. That’s how one formula works on 21 symptoms.

Most “menopause complexes” stack 15 to 30 botanicals, each at a fraction of the clinically studied dose. It looks impressive on a label; it rarely works in a body. Vesper picked nine — and dosed each one exactly at the level used in the peer-reviewed trials that validated it.

More ingredients is a marketing decision. Nine actives is a pharmacological one.

The formula supports the 21 symptoms most commonly reported during peri-menopause, grouped into four pillars:

Sleep & night cycle — 3 AM wake-ups, insomnia, night sweats, non-restorative sleep.
Hot flashes & thermoregulation — daytime flashes, social flushing, temperature dysregulation.
Mind & mood — brain fog, new-onset anxiety, mood swings, irritability, crying spells.
Energy & metabolism — fatigue, abdominal weight gain, slowed metabolism, sugar cravings, glucose crashes.
Body — muscle tension, palpitations, hormonal migraines, libido.

No. Vesper contains no synthetic or bioidentical hormones. It is a dietary supplement, not a prescription medication. One of our actives — Rhapontic Rhubarb — is a Selective Estrogen Receptor Modulator (SERM): it interacts with a specific estrogen receptor subtype (ERβ) without adding estrogen to your body. If you are currently on HRT or considering it, please consult your physician. Vesper is not a substitute.

Yes. Vesper is produced in a cGMP-certified (current Good Manufacturing Practices) facility — the same quality standard applied to pharmaceutical manufacturing in the United States. Every batch is independently tested for identity, potency, heavy metals, and microbial contamination before it leaves the facility. FDA-approval applies to drugs, not supplements — but manufacturing rigor is a choice, and it's one we've made.

Rhapontic Rhubarb (Rheum rhaponticum), standardized and dosed at 40 mg. In a 12-week double-blind clinical trial of 109 peri-menopausal women published in Menopause (the journal of the North American Menopause Society, 2006), Rhapontic was associated with a 68% reduction in hot flash frequency and severity.

It works through a targeted mechanism — selective binding to the estrogen receptor beta (ERβ) — without estrogenic activity at the body level. This is the active that anchors the formula.

It's the absorption amplifier. Black Pepper extract standardized to 95% piperine significantly increases the bioavailability of botanical actives — without it, a meaningful portion of what you swallow passes through unabsorbed. It's why every serious clinical-dose formula includes it.

Yes. Every ingredient on the Vesper label is printed with its full milligram dose and standardization percentage — not hidden inside a “proprietary blend.” You can cross-reference each one against the published clinical trial that anchors it.

We’d rather be transparent about nine actives that hit clinical dose than vague about twenty that don’t.

Women in peri-menopause — typically late thirties through early fifties — experiencing the hormonal transition in real life: disrupted sleep, hot flashes, brain fog, mood changes, unexplained weight shift, irregular cycles. Designed for women who want a formula dosed at clinical levels, backed by published research, rather than a drugstore multi.

Peri-menopause is the hormonal transition before your last period — it can begin up to 10 years before menopause itself, typically between 40 and 50 (sometimes earlier). Common signs: cycle irregularity (shorter, longer, heavier, lighter), sleep disruption, hot flashes or night sweats, new-onset anxiety, brain fog, and unexplained mood or weight changes.

Most physicians don’t routinely screen for it, and blood tests are unreliable because hormone levels fluctuate. If you recognize the pattern, you’re almost certainly in it.

Yes, if you're experiencing symptoms. Peri-menopause can begin in the late thirties — earlier than most women expect, and earlier than most doctors acknowledge. You don't need a lab test or a formal diagnosis. Disrupted sleep, shifting mood, changes in your cycle: that's enough to start.

Most women notice the earliest shifts within the first 2 weeks — typically around sleep and nervous-system calm. Hot flashes tend to reduce between weeks 3 and 6. Metabolic and libido shifts build over 6 to 8 weeks. The full clinical window for each active is 8 weeks.

Deeper sleep with fewer 3 AM wake-ups. Reduced night sweats. A calmer nervous system — you may notice you’re less reactive during the day. Easier mornings. These are the Ashwagandha and magnesium effects arriving first.

Weeks 3–6: Hot flash frequency and intensity begin to reduce, driven by Rhapontic Rhubarb and Black Cohosh. Focus sharpens, brain fog lifts, mood stabilises with fewer sharp edges.

Weeks 6–8: Metabolic improvements become measurable — steadier energy, reduced abdominal weight gain, more regulated blood glucose (Berberine's full clinical window). Cortisol baseline lowers. Some women notice improvements in libido and fewer hormonal migraines.

These are the timelines documented in the peer-reviewed trials. Individual results vary, which is why the guarantee is 60 days — not 8 weeks.

No. Peri-menopause is a transition, not a disease. Many women take Vesper consistently through the active symptomatic years (typically 2 to 7 years), then taper off or use it seasonally when hot flashes flare. Others continue indefinitely for metabolic and sleep support. You stay in control.

Two things. First: peri-menopause is individual — sleep responders, hot flash responders and metabolic responders don’t always overlap. Some women feel it in week 2; some need the full 8-week clinical window.

Second: if within 60 days you haven’t noticed meaningful improvement on your primary symptoms, we refund you. No forms. No questions.

Two capsules, once a day. Taken together, they deliver the full clinical dose of each of the nine actives — no splitting required, no math, no half-dose compromises.

Morning, with breakfast. Both capsules together — no splitting needed. The food context is important: Berberine works best with a meal for glucose regulation and GI tolerance, and the rest of the formula performs well taken consistently at the same time each day. If your mornings are light, a piece of fruit or yoghurt is enough.

The nine actives have been studied individually in peer-reviewed human clinical trials for decades. Each is dosed at or within the standard clinically studied range. That said, “safe for most people” is not “safe for everyone” — we recommend speaking with your physician if you’re on medication or managing a condition.

The most commonly reported effects are mild and transient: occasional gastrointestinal adjustment in the first week (Berberine), and mild initial drowsiness with evening dosing (Ashwagandha, magnesium). These typically resolve within days. Discontinue and consult a physician if you experience any unusual or persistent reaction.

This is a conversation to have with your prescribing physician. Vesper contains no hormones, but Rhapontic and Black Cohosh interact with estrogen-pathway signaling. Many women on low-dose HRT combine it with botanical support; the decision belongs with your clinician.

Consult your physician before combining. There is no established contraindication between Vesper's actives and standard SSRIs or SNRIs, but Ashwagandha has mild serotonergic activity. If you're on an SSRI or in a titration phase, flag it with your prescriber — a brief conversation, not a blocker.

No. Vesper is not intended for use during pregnancy, while trying to conceive, or while breastfeeding. Black Cohosh, Rhapontic and Berberine are all contraindicated in these contexts.

Do not start Vesper without a direct conversation with your oncologist or physician. Although Rhapontic is ERβ-selective and Black Cohosh shows no estrogenic activity in breast tissue in published research, any personal or family history of hormone-sensitive cancer requires clinician review.

Estroven is a mass-market drugstore product with a minimal ingredient list at sub-clinical doses, designed for shelf-price competition. Vesper is a direct-to-consumer premium formula with nine clinically-dosed actives, full transparency on every dose, and the studies cited on every claim. The category, the audience and the pricing tier are simply different.

Happy Mammoth leans on aggressive marketing and broader claims than we’re comfortable making. O Positiv is designed for a millennial wellness aesthetic and a younger demographic. Vesper is built for women who want to understand what they’re putting in their body — rigorous, transparent, without the flashy or pastel register.

Clinical doses cost more than trace doses. Clinically-standardized ingredients (Ashwagandha root extract, Black Pepper extract at 95% piperine) cost more than generic bulk powders. Batch-by-batch testing costs more than skipping it. A cGMP manufacturing run costs more than a lower-tier facility. If a formula is dramatically cheaper than ours, one of those lines is where the math was done.

Each active is sourced from the supplier with the strongest clinical data on that specific compound. Rhapontic Rhubarb extract originates from Europe, where the foundational Rhapontic Rhubarb clinical programme was conducted. Ashwagandha root extract is standardised to 5% withanolides and sourced from Indian cultivation with pharmacopoeial identity testing. All ingredients undergo identity verification, potency testing, and heavy metal screening before formulation. Supply chain is fully traceable.

Yes to both. Vesper is manufactured in a cGMP-certified facility and every batch is independently tested for identity, potency, heavy metals, and microbial contamination before it ships. If a batch doesn't meet specification, it doesn't leave the facility.

Yes to all three. Vesper contains no animal-derived ingredients, no GMO components, and none of the 9 FDA-recognised allergens: milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soy, or sesame. No gluten. The full supplement facts panel is printed on every bottle.

Orders leave our facility within 1–2 business days. Standard shipping takes 5 to 8 business days. Expedited options are available at checkout.

Yes — multi-bottle pricing is available on the product page.

60 days. Satisfaction or your money back. No forms. No questions.

If within 60 days of your order you haven’t felt meaningful improvement on your primary symptoms, email us and we refund you. We’ll refund you because we believe you.

Vesper was founded by Claire, after a 2021 episode in Brooklyn that sent her home from work mid-Tuesday at 44 and didn’t let her come back for 8 months. Her diagnosis was burnout. Her actual condition was undiagnosed peri-menopause.

Her exact words, on the About page: “I thought I was losing my mind. I was actually losing my estradiol.”

She went from reading emails to reading endocrinology papers, built a team that could read them with her, and formulated Vesper at clinical doses because the supplements she’d tried weren’t.

Read the full story

Section 11 of this page lists every clinical reference with a direct PubMed link — open any study and judge the evidence yourself. For the full ingredient science library, visit the Ingredients & Science page.