# 10 | PMS vs PMDD: Understanding the Difference and What You Can Do

Most women are familiar with the emotional ups and downs, bloating, tiredness, or irritability that can show up in the week or so before a period, this constellation of symptoms is often labelled “PMS” (premenstrual syndrome). It’s so common that up to three in four women experience some symptoms before menstruation at some point in their lives.

But there’s another condition that looks similar on the surface yet feels very different in lived experience: Premenstrual Dysphoric Disorder (PMDD). Though it occurs in the same phase of the cycle and shares some symptoms with PMS, PMDD is not simply “PMS on steroids.” It’s a distinct clinical condition with intense emotional and behavioural symptoms that can disrupt work, relationships, and daily functioning.

What Are PMS and PMDD?

PMS involves a mix of emotional and physical symptoms, such as irritability, mood swings, bloating, fatigue, and breast tenderness, that begin in the luteal phase (about 7–10 days before your period) and ease within a few days of menstruation starting.

PMDD, on the other hand, is a more severe condition recognised in clinical diagnostic manuals. It is characterised by intense emotional symptoms, such as overwhelming sadness, anxiety, extreme irritability, and feelings of hopelessness, alongside physical discomfort. These symptoms are severe enough to interfere with daily life and can even feel disabling. Discovery Institute

PMDD affects a smaller percentage of women than PMS - estimates suggest around 3–8% of people who menstruate, but its impact can be profound.

How Are They Different?

The key difference isn’t just the intensity of symptoms, but the degree to which they interfere with life:

With PMS, symptoms may be uncomfortable but don’t typically prevent you from functioning normally.

With PMDD, emotional symptoms like anxiety, depression, or anger are more intense and consistent, and they can make work, relationships, and daily responsibilities harder to manage. Discovery Institute

Both conditions occur in the luteal phase and resolve once menstruation begins, but PMDD’s emotional symptoms dominate and significantly disrupt quality of life. Healthline

Why These Differences Matter

Understanding the distinction between PMS and PMDD isn’t about minimising women’s experiences or making excuses. It’s about recognising when symptoms go beyond normal cyclical changes and require support and intervention. Many women with PMDD go years without a diagnosis because their suffering is dismissed as “just bad PMS.” This delays care and deepens the emotional burden.

What You Can Do

If you recognise patterns of mood swings, anxiety, depression, or irritability that rise and fall with your cycle and especially if these symptoms are interfering with your life, daily tracking can be helpful. Recording your symptoms over two or more cycles helps clarify whether what you’re experiencing matches clinical criteria for PMDD.

Talking with a healthcare provider who understands menstrual-related mood disorders is also key. Treatments can vary from lifestyle adjustments and nutritional support to targeted therapies such as SSRIs or hormonal interventions, depending on the severity and your personal health profile. Healthline

You’re Not Alone But Your Symptoms Deserve Attention

Both PMS and PMDD arise from normal hormonal fluctuations, but the way your body and brain respond matters. These are not “in your head” in a dismissive sense, they are real, cyclical, and modifiable with the right support.

At HER, we stand with you in seeking clarity, respect, and evidence-based care. Your cycle matters, and understanding it better is a step toward reclaiming your health and not just enduring it.