Why Perimenopause Causes Mood Swings — And What the Neurotransmitter Research Suggests

Someone asked me last month why she felt like she'd become a different person. She was 47, snapping at people she loved, crying in the car for no reason she could name, lying awake at 3 a.m. with her heart going. Her words were the ones I hear most: "This isn't me. I don't recognize myself." I've sat where she's sitting. So I want to tell you what I've learned — not as a doctor, because I'm not one, but as someone who went looking for the why and found that the why is real, physical, and has very little to do with your character.

The short answer

Perimenopausal mood swings are not a personality change. They are a neurochemical event. As estrogen falls and fluctuates through your forties and early fifties, two things happen at once: low-grade inflammation rises across the body and brain, and the brain chemistry that keeps mood steady — serotonin and GABA in particular — gets harder to maintain. The research that's emerged in the last decade frames perimenopause itself as a "systemic inflammatory phase" that disrupts estrogen-regulated systems in the brain.¹ That's the bridge almost no one explains: the inflammation and the mood are connected, and estrogen sits in the middle of both.

If you're researching non-hormonal options, the nutrients with the most plausible mechanism behind them are the ones that support serotonin and GABA signaling — 5-HTP (a serotonin precursor), GABA itself, Panax ginseng (for the stress-axis side), and vitamin B6 (the cofactor your body needs to build serotonin in the first place). None of these is a treatment for a mood disorder. They are support for a system under strain. I'll explain where each one fits, and just as importantly, where the evidence runs thin.

Why estrogen falling changes your mood — the actual mechanism

Here's the thing nobody told me. Estrogen isn't only a reproductive hormone. In the brain it behaves like a regulator — it helps keep inflammation in check and it supports the machinery that makes and uses serotonin. The science on this is genuinely complex; one major review in Endocrine Reviews spends seventy pages on how estrogen can be anti-inflammatory in some contexts and pro-inflammatory in others, depending on dose, timing, and tissue.² The honest summary is: estrogen is deeply woven into your inflammatory and neurochemical balance, so when it starts swinging and declining, that balance wobbles.

Step one: estrogen decline, inflammation up

When estrogen drops, the body's inflammatory tone tends to rise. A 2025 analysis from the Study of Women's Health Across the Nation — SWAN, one of the largest long-running studies of the menopause transition — found that inflammatory markers, specifically high-sensitivity C-reactive protein and interleukin-6, follow distinct upward patterns of change across the menopause transition in midlife women.³ This isn't the redness-and-swelling kind of inflammation you'd notice. It's quiet, systemic, the kind you only see on a blood panel. But the brain notices it.

Step two: inflammation reaches the brain

This is the part that reframed everything for me. A 2020 review in the Journal of Neuroinflammation describes perimenopause as a pro-inflammatory phase that disrupts estrogen-regulated neurological systems — the authors describe how ovarian changes release inflammatory signals that can affect the blood-brain barrier and the brain's own inflammatory regulation.¹ When the brain's inflammatory tone rises, the systems that keep mood steady have to work against a headwind.

Step three: serotonin gets harder to maintain

Serotonin is the neurotransmitter most associated with steady mood. It's built from an amino acid (tryptophan), converted first into a compound called 5-HTP, and then into serotonin itself. Estrogen normally supports this pathway. As estrogen falls, the support falls with it — and the inflammatory state in the background can pull tryptophan down a different metabolic road, leaving less of it available to become serotonin. So you get a system that's both less supported and more taxed. That's not a metaphor for feeling unstable. That is the instability.

When I finally understood this sequence — estrogen down, inflammation up, serotonin harder to hold — the 3 a.m. heart-pounding stopped feeling like a flaw in me. It started feeling like weather. Weather you can prepare for.

What the neurotransmitter research suggests — and the honest limits

I want to walk through the four nutrients that map onto this pathway, because the mechanism is what makes them worth a look. I'll be straight with you about the evidence quality each time. Some of it is strong; some of it is suggestive; none of it is a cure.

5-HTP — the serotonin precursor

5-HTP is one metabolic step away from serotonin. Because it crosses into the brain and feeds directly into serotonin synthesis, it's the most mechanistically direct option for the serotonin side of the story. A comprehensive 2020 review in the International Journal of Molecular Sciences lays out its physiology and its role as a serotonin precursor in both neurological and metabolic conditions.⁴ There's also intriguing work showing 5-HTP and serotonin signaling intersect with inflammation directly — in an animal model, 5-HTP supplementation reduced inflammatory arthritis markers, a reminder that the serotonin system and the immune system talk to each other.⁵

The honest limit: the clinical trial evidence in menopausal women specifically is thin, and 5-HTP interacts seriously with antidepressants (SSRIs, SNRIs, MAOIs). This is not something to combine with a prescription on your own. If you take anything for mood, this is a conversation-with-your-doctor item, full stop.

GABA — the calming signal

If serotonin is steadiness, GABA is the brake. It's the brain's main inhibitory neurotransmitter — the one that quiets the noise. A small human study published in BioFactors found that oral GABA increased alpha brain waves (the relaxed-but-alert state) and was associated with markers of reduced stress within about an hour of taking it.⁶ That's a small study, and how much oral GABA reaches the brain is genuinely debated among researchers. But the direction of the finding — calming, fast — lines up with what the irritability-and-anxiety side of perimenopause is actually about.

The honest limit: one small study is one small study. GABA's value here is plausibility plus a clean safety record, not a stack of trials.

Panax ginseng — the stress-axis support

The 3 a.m. wake-up isn't only a serotonin story; it's also a stress-hormone story. Panax ginseng is an adaptogen traditionally used for exactly this kind of "wired and tired" state, and the modern interest is in its active compounds, ginsenosides. A 2017 review in the Journal of Ginseng Research describes how ginsenosides modulate inflammatory signaling pathways, including NF-kB — the master switch that the whole inflammation story turns on.⁷ So ginseng touches the inflammation side and the stress-resilience side at once.

The honest limit: ginseng's mood evidence in perimenopausal women is preliminary. I'd frame it as stress-axis support, not an antidepressant.

Vitamin B6 — the quiet cofactor

This one is unglamorous and easy to overlook, which is exactly why I want to name it. Your body cannot build serotonin from 5-HTP without vitamin B6 (specifically its active form). It's the cofactor in the final step. If you're low — and a meaningful number of midlife women run low on B-vitamins — you can have all the precursor in the world and still not make enough serotonin. B6 doesn't lift mood on its own; it makes the rest of the machinery run.

The honest limit: more is not better. Very high long-term doses of B6 can cause nerve problems. The point is sufficiency, not megadosing.

What works, what doesn't, and what the internet keeps getting wrong

What the mechanism supports: supporting serotonin synthesis (5-HTP plus its B6 cofactor), supporting the calming GABA signal, and supporting the stress axis (ginseng) — while addressing the inflammatory background that estrogen decline kicks up. The multi-pathway framing matters because perimenopausal mood isn't one broken thing. It's several systems leaning at once.

What the evidence doesn't support: the idea that any single supplement "balances your hormones." Nothing on this page raises estrogen. These nutrients work downstream of the hormone change, on the neurotransmitter and inflammatory systems the hormone change disrupts. That's a real place to intervene, but be suspicious of anything promising to fix the hormones themselves.

What the internet keeps defaulting to: magnesium and St. John's Wort. Magnesium is fine and worth having in your diet, but it's not the serotonin-and-inflammation story. And St. John's Wort interacts with an alarming number of medications, including hormonal birth control. Neither addresses the inflammation-to-serotonin bridge that I think is the actual heart of perimenopausal mood change.

And the most important non-supplement truth: if your mood symptoms are severe — if you're having thoughts of not being here, if you can't function — that is a medical situation, not a supplement situation. Please call your doctor. Supplements are for support around the edges of a normal-but-hard transition, not a substitute for care.

A note on what Fabio built

I don't usually lead with the product, because that's not why I write these. But it would be strange to walk you through this pathway and not tell you that it's the same pathway Fabio built our formula around. When my own medication left me in chronic pain and the only thing offered was daily NSAIDs for the rest of my life, he went looking for something that addressed the root — inflammation — rather than just muting the signal. ProleevaMax carries 5-HTP, GABA, Panax ginseng, and vitamin B6 among its thirteen standardized ingredients, alongside the anti-inflammatory actives, precisely because the mood side and the inflammation side aren't separate problems. They're the same problem wearing two faces. I take it. He made it for me first.

That's the only sales pitch you'll get from me: if the mechanism on this page makes sense to you, a multi-pathway formula is one honest way to act on it. Read the label, trace the doses, ask your doctor. That's all I'd ask of anything I put in my own body.

Frequently asked questions

Are perimenopause mood swings a sign of depression?

Not necessarily — but the line can blur, which is why honesty here matters. Perimenopausal mood changes come from fluctuating estrogen, rising inflammation, and strained serotonin and GABA signaling, and they often track with your cycle changes and hot flashes. Clinical depression is more persistent and pervasive. If low mood lasts most of the day nearly every day for two weeks or more, or you have thoughts of self-harm, treat it as depression and see a doctor — don't wait it out as "just perimenopause."

Which supplement is best for perimenopause anxiety and irritability?

There's no single best one, because anxiety and irritability in perimenopause come from more than one system. For the calming side, GABA has a small but suggestive human study behind it.⁶ For the underlying serotonin side, 5-HTP (with vitamin B6 as its cofactor) is the most mechanistically direct.⁴ For the "wired and tired" stress-axis piece, Panax ginseng is the traditional adaptogen option.⁷ A formula that addresses several at once reflects the biology better than any single nutrient.

Can I take 5-HTP if I'm on an antidepressant?

Not without your doctor's sign-off. 5-HTP raises serotonin, and combining it with SSRIs, SNRIs, or MAOIs can push serotonin too high — a genuinely dangerous interaction. This is the most important safety point on this page. If you take anything for mood, anxiety, or migraine, clear 5-HTP with your prescriber first.

Why does my mood crash at night specifically?

Two reasons that reinforce each other. Estrogen's daily rhythm and your declining levels can leave the evening hours under-supported, and the stress hormone cortisol can spike in the small hours, waking you with a pounding heart. That's why both the serotonin side (steady daytime mood) and the stress-axis side (ginseng, GABA) show up in this conversation — perimenopause is as much a nighttime problem as a daytime one.

How long before I'd notice anything?

Nutritional support works gradually, not like a switch. Most botanical and amino-acid research evaluates outcomes at 8 to 12 weeks. Give any approach a fair, consistent trial of about 90 days, track specific things (sleep quality, how often you're snapping, the 3 a.m. wake-ups) in a simple log rather than relying on memory, and bring that log to your doctor.

— Maria

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Always talk with your healthcare provider before starting a new supplement, especially if you take antidepressants, hormonal medications, or other prescriptions.

Related reading

• Best supplements for menopause brain fog
• Inflammation and brain fog — the biological connection most people miss
• Pain signals and the quieting response — how GABA modulates what you feel
• The neurochemistry of feeling good — what actually moves the needle on mood

References

1. McCarthy M, Raval AP. The peri-menopause in a woman's life: a systemic inflammatory phase that enables later neurodegenerative disease. J Neuroinflammation. 2020;17(1):317. https://doi.org/10.1186/s12974-020-01998-9
2. Straub RH. The complex role of estrogens in inflammation. Endocr Rev. 2007;28(5):521-574. https://doi.org/10.1210/er.2007-0001
3. El Khoudary SR, Chen X, Qi M, et al. The relation between systemic inflammation and the menopause transition: the Study of Women's Health Across the Nation. J Clin Endocrinol Metab. 2025;110(11):e3566-e3576. https://doi.org/10.1210/clinem/dgaf175
4. Maffei ME. 5-Hydroxytryptophan (5-HTP): natural occurrence, analysis, biosynthesis, biotechnology, physiology and toxicology. Int J Mol Sci. 2020;22(1):181. https://doi.org/10.3390/ijms22010181
5. Yang TH, Hsu PY, Meng M, Su CC. Supplement of 5-hydroxytryptophan before induction suppresses inflammation and collagen-induced arthritis. Arthritis Res Ther. 2015;17(1):364. https://doi.org/10.1186/s13075-015-0884-y
6. Abdou AM, Higashiguchi S, Horie K, Kim M, Hatta H, Yokogoshi H. Relaxation and immunity enhancement effects of gamma-aminobutyric acid (GABA) administration in humans. BioFactors. 2006;26(3):201-208. https://doi.org/10.1002/biof.5520260305
7. Kim JH, Yi YS, Kim MY, Cho JY. Role of ginsenosides, the main active components of Panax ginseng, in inflammatory responses and diseases. J Ginseng Res. 2017;41(4):435-443. https://doi.org/10.1016/j.jgr.2016.08.004