Every month, like clockwork, something shifts.
You're more irritable. More anxious. Things that wouldn't normally get to you suddenly do. You snap at people you love. You cry at something small. You feel like you're not quite yourself — and then your period arrives and within a day or two, you're back.
Sound familiar?
Here's what nobody tells you: that's not you being difficult. That's not you being too emotional or too sensitive. That is your brain responding to a very real hormonal event — one with a documented neurological mechanism that affects millions of women every single month.
Here's What's Actually Happening — Simply
Your cycle runs on two main hormones: oestrogen and progesterone. They rise and fall across 28 days in a pattern that looks like this:
Look at what happens from around day 21 onward.
Both hormones — which have been supporting your mood, your sleep, and your sense of calm — start to drop. By day 25 or 26, they fall off sharply. That drop is the PMS zone.
Here's why that matters for your mood.
Estrogen directly supports serotonin — your brain's primary mood-stabilising chemical. When oestrogen drops, serotonin drops with it. Less serotonin means lower mood, higher irritability, and a reduced ability to handle stress. A drop in serotonin also happen right after ovulation, when estrogen drops mid-cycle - many women experience PMS symptoms here as well.
Progesterone, meanwhile, metabolises in the brain into a natural calming compound. Think of it as your body's built-in anxiety buffer. When progesterone drops sharply before your period, that buffer disappears almost overnight. Your nervous system loses its cushion. It becomes more reactive — more sensitive to everything.
That's not you being weak. That's two mood-supporting hormones withdrawing at the same time.
When to take it seriously
PMS is real and disruptive for a lot of women. But there's a more severe form called PMDD — Premenstrual Dysphoric Disorder — and it's worth knowing the difference.
PMDD isn't just intense PMS. It's a mood disruption severe enough to significantly affect your relationships, your work, and your ability to function. Debilitating depression. Rage that feels uncontrollable. Anxiety so intense it's paralysing — consistently, every single cycle.
If that sounds like you, please take it seriously. PMDD is a diagnosable condition with evidence-based medical treatments. You should not be managing it alone.
Track your symptoms across two or three cycles. When do they start? When do they lift? If the pattern is tight around your luteal phase (the time leading up to your periods), bring that data to a gynaecologist or doctor who understands hormonal mood disorders.
What makes PMS worse
Knowing what amplifies it is just as useful as knowing what causes it.
Poor sleep. Sleep deprivation raises cortisol and drops serotonin — both of which worsen premenstrual mood directly. If your sleep is already disrupted in the week before your period, the mood impact compounds quickly.
Stress. Chronic stress keeps cortisol elevated. Cortisol and the calming compounds your brain produces are directly antagonistic. Going into your luteal phase already stressed means the hormonal drop lands on a nervous system already running on edge.
Alcohol. It feels calming when you're anxious and premenstrual. But as it metabolises, it suppresses your brain's ability to regulate itself and leaves your nervous system more reactive. It reliably worsens PMS mood — even when it feels helpful in the short term.
What this means for you
You can't stop progesterone and estrogen from dropping. That's just your cycle.
But you can change the conditions in which they drop.
When the inflammatory baseline in your body is lower — when your hormonal environment is better supported going into the luteal phase — the drop is less disruptive. The shift still happens. But it doesn't knock you sideways.
This is the thinking behind Period therapy by The Alpine Apothecary - a 100% natural, clinically formulated herbal blend that works on the root hormonal and inflammatory drivers of menstrual symptoms — including the mood disruption of the luteal phase. This is a natural but science-backed reset — so your cycle stops derailing you every month.
The bottom line
Look at that chart again. The PMS zone isn't random. It's the predictable result of two hormones withdrawing at the same time — taking your mood buffer and your serotonin support with them.
You're not too emotional. Your biology is asking for support.