PMS vs PMDD: Understanding the Key Differences

What's actually the difference between PMS and PMDD — and how do you know which one you're dealing with? In this episode, Dr Georgina Standen breaks down the two conditions clearly, without the mystique.

In this episode:

• What defines PMS, and why it's so common
• What makes PMDD a distinct, more severe condition — not just "worse PMS"
• Why there's no blood test for either, and what tracking actually shows
• How diagnosis leads to different treatment paths

Mentioned in this episode:

• Belle app: https://bellehealth.co/
• Sirona Health PMS/PMDD page: https://www.sironahealth.co.uk/pms

Sirona Health Podcast is hosted by Dr Georgina Standen, GP and founder of Sirona Health (sironahealth.co.uk), a specialist women's health practice covering menopause, PMS/PMDD and teen health. Book a consultation at sironahealth.co.uk.

This podcast is for general information only and doesn't replace individual medical advice — please speak to your GP or a specialist about your own symptoms. If you're struggling, please reach out for support.

Transcript

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Speaker 0:04

Hormones don't just run your cycle, they run your mood, your mind, your whole sense of self. I'm Dr. Georgina Standen, GP and founder of Sirona Health, and this is the Sirona Health Podcast, where we talk about the relationship between female hormones and mental health properly, without the mystique and without the dismissal. So I wanted to start this series with PMS and PMDD because it's probably the thing I get asked to untangle most often in clinic. Someone will come in and say, I don't know if this is just PMS or if it's something more, and actually, most of the time, once we sit down and go through it properly, it's a pretty clear distinction. It's just that nobody's ever laid it out for them in plain terms before. So that's what I want to do today. What PMS actually is, what PMDD actually is, and how you tell the two apart. I think in clinic, this is probably the mix-up I see the most. I'll have women in their 30s, 40s, sitting across from me, and they spent years just assuming this is who they are. Someone's told them it's stress, someone's told them it's anxiety, and nobody's ever really asked about their cycle. And then, less often, but it does happen, I'll see the opposite. Someone's read about PMDD online and is fairly convinced that's what they've got. When actually, when we go through it properly, what they're describing is PMS. Neither of those is anyone being silly, it's just that nobody's ever sat down and laid out the actual difference. So that's what I want to do. So PMS, premenstrual syndrome, is really an umbrella term for physical and emotional symptoms that turn up in the run-up to your period. That's the luteal phase, so the second half of your cycle after you've ovulated. And I think it's worth saying this is genuinely properly common. Most women who have periods will notice something: bloating, sore breasts, headaches, feeling a bit flat or a bit snappy, tired, off your food, or wanting to eat everything in the cupboard. For most people it's noticeable, maybe a bit annoying, but it doesn't really take over their life. So what makes it PMS specifically? It shows up after ovulation. It settles down within a few days of your period starting, and I think this is the important bit. It's bothersome, but you can still function. You're still going to work, you're still showing up for people. And then there's PMDD. PMDD is a different thing altogether. Premenstrual dysphoric disorder, much rarer than PMS, but so much more severe. This is where it stops being a bit much and starts being genuinely disabling, real despair, anxiety that grips you, anger that doesn't feel like you at all. And it doesn't just sit there, it stops you functioning. Work suffers, relationships suffer. I've had women describe it to me as not recognizing themselves for that week or two of the month. There's a clinical threshold for it too. You need a certain number of symptoms, including at least one core mood symptom, and it has to follow that same tight monthly pattern, tied to the luteal phase, and it has to cause real distress or getting in the way of your life. And I want to be clear about this because I think it matters. PMDD isn't just PMS but worse, it's its own condition, and it gets missed constantly. It's mistaken for depression, mistaken for an anxiety disorder, and sometimes even mistaken for bipolar disorder, which is something I want to come back to properly in a later episode. So how do you actually tell? This is a bit that surprises almost everyone I say it to. There's no blood test for this. You can't work out PMS versus PMDD from a hormone panel. And I think this is honestly one of the biggest things I want people to take from this whole series. Most women with PMS or PMDD have completely normal hormone levels. It was never really about how much estrogen or progesterone you've got. It's about how sensitively your brain reacts to the completely normal ups and downs every cycle brings. So instead, what we do is track properly, daily, for at least two cycles, so we can actually see the pattern. Does it show up after ovulation every time? And does it settle down once your period starts? There are quick screening tools like the PSST, which gives us a first read. But the real gold standard is just tracking it yourself day by day. An app like Bell makes that pretty easy. Honestly, even a paper calendar on the fridge works fine. One thing worth flagging: if you've had a hysterectomy but kept your ovaries, or you're not having periods for another reason, like an ablation or a hormonal coil, tracking gets a bit trickier. There are other ways around that, and I'll go into it properly when we talk about cycle mapping in a later episode. Once we know what we're dealing with, I think treatment stops being a bit of a guessing game. For PMS, we're usually starting fairly simple. Sleep, movement, nutrition, maybe CBT, sometimes supplements like magnesium or calcium. For PMDD, we're usually looking at something a bit more targeted. SSRIs, which actually tend to work faster here than they typically do for general depression, or tailored contraceptive approaches, and in more severe cases, hormonal suppression under specialist supervision. There's one more thing worth mentioning before we wrap up: something called premenstrual exacerbation. That's where an existing condition gets significantly worse premenstrually, without any new symptoms showing up. It's a different pattern again, and I think it deserves its own episode later on. So if there's one thing I'd want you to take from today, it's this. If your symptoms are getting in the way of your work, your relationships, your sense of who you are for a real chunk of every month, that's not something you should just have to live with. And if you've tried the self-care things and it hasn't really touched it, I don't think that's you failing. I think that's information. If any of this has landed with you, it might be worth tracking your next cycle or two before we go further. I think it will make everything else in this series click into place a bit more. I'll put the app links in the show notes. That's it for today. I'm Georgina. Thanks for listening. A quick note before you go this podcast is for general information, not individual medical advice. It doesn't replace seeing your own GP or a specialist. So if anything you've heard today feels relevant to you, please do talk to someone. And if you're struggling, please reach out to your GP, to someone you trust, or to a crisis line if you need one right now. You can find Sirona Health and book your appointment at sironahealth.co.uk. See you next time.