What is premenstrual dysphoric disorder? And how is it different to PMS?

Periods can feel like an unwanted guest for many women and gender diverse people who menstruate, bringing cramps, mood swings and exhaustion.

But how do you know if what you are experiencing is standard premenstrual syndrome (PMS), or something more severe?

Premenstrual dysphoric disorder (PMDD) and the premenstrual exacerbation of an existing mental illness can also occur in the lead up to your period.

What’s the difference?

Premenstrual syndrome

This is an umbrella term for mild to moderate emotional and physical symptoms that start a few days before your period. This includes bloating, mood swings, irritability and fatigue. Up to 98% of women experience PMS during their reproductive years.

While many PMS symptoms are uncomfortable, most women can effectively manage them without much issue. You might feel cranky or tired, but you can still manage daily tasks.

Premenstrual dysphoric disorder

This is a more severe form of PMS, occurring in 3–9% of women. Symptoms include extreme mood changes, anxiety, anger and even depression in the days leading up to a period.

Premenstrual dysphoric disorder symptoms are more severe than PMS. Mood changes can feel overwhelming and make even small daily tasks feel much more challenging. Symptoms can be so intense, it can be hard to go to school, work, or to socialise.

Premenstrual exacerbation

This is a similar premenstrual condition, where symptoms of existing mental health conditions noticeably worsen in the days leading up to a period.

If you already experience an anxiety condition, for example, premenstrual exacerbation could see your anxiety heightened in the days leading up to your period.

What causes these conditions?

These conditions are linked to the natural rise and fall of hormones during the menstrual cycle.

Two key hormones – estrogen and progesterone – shift throughout the month, particularly in the second half of the cycle (luteal phase) when progesterone increases, and estrogen decreases.

These changes can affect brain chemicals such as serotonin, which help regulate mood, leading to irritability, mood swings and low energy.

Not all women experience these symptoms in the same way. Some are more sensitive to hormonal changes, which may be influenced by factors such as genetics, past trauma, or pre-existing mental health conditions. These differences help explain why some women have more severe or distinct symptoms compared to others.

How are these conditions diagnosed?

GPs and mental health practitioners such as psychiatrists and psychologists play a key role in identifying potential issues by understanding what is classified as normal premenstrual symptoms for each woman.

But menstrual history is often overlooked in mental health assessments.

For a correct diagnosis, GPs and mental health practitioners should ask detailed questions about both physical and emotional symptoms across the menstrual cycle, such as:

• do you experience mood swings, irritability, or feelings of sadness at specific times in your cycle?
• do you have physical symptoms such as bloating, breast tenderness or headaches?
• how do these symptoms affect your daily life or relationships?
• do the symptoms disappear completely once your period starts or shortly after?

Clinicians can diagnose PMS and premenstrual dysphoric disorder. But premenstrual exacerbation is not a formal diagnosis: it describes the worsening of existing mental health conditions. This may require referral to a mental health professional for further assessment.

Premenstrual exacerbation can mimic mood swings seen in bipolar disorder, so it’s important your GP and/or mental health provider make detailed inquiries about menstrual patterns and symptoms to avoid misdiagnosis.

Diagnosing premenstrual dysphoric disorder can be a lengthy process, as it requires patients to track their symptoms over at least two menstrual cycles and keeping daily records.

Symptoms must meet specific thresholds, including at least five out of 11 key symptoms listed in diagnostic criteria (such as marked mood swings, irritability, or physical discomfort) and demonstrate significant interference with daily life.

Symptoms must be tracked for two full menstrual cycles to confirm these patterns and rule out other conditions, such as depression or anxiety, that may not follow a cyclical pattern.

What are the treatment options?

If your GP suspects you have PMS, premenstrual dysphoric disorder or premenstrual exacerbation of an existing mental health condition, treatment options can include:

Lifestyle changes

Regular exercise, a balanced diet and good sleep hygiene can help manage PMS symptoms, but not premenstrual dysphoric disorder or premenstrual exacerbation.

Medication

Hormonal treatments can effectively manage premenstrual dysphoric disorder or premenstrual exacerbation symptoms, as both are linked to hormone fluctuations. Hormonal contraceptives, for instance, can help stabilise hormone levels and reduce the intensity of emotional and physical symptoms.

My (Jayashri) recent research has shown the oral contraceptive Zoely, which contains bioidentical hormones, is effective in treating the mood symptoms of premenstrual dysphoric disorder. Bioidentical hormones are chemically identical to those the body naturally produces, so they may cause fewer side effects than synthetic hormones.

Antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), are another option for premenstrual dysphoric disorder, either taken continuously or for seven to ten days before menstruation.

For women with premenstrual exacerbation, adjusting existing medications or adding hormone treatments during the premenstrual period can be beneficial.

Therapy

Cognitive behavioural therapy (CBT) and dialectical behaviour therapy (DBT) have been shown to help women manage the emotional impacts of worsening mental health symptoms before a period.

CBT targets negative thought patterns and behaviours to improve emotional regulation, while DBT builds skills like mindfulness and distress tolerance to manage intense emotions and relationships.

Supplements

Some women may find relief with over-the-counter supplements such as calcium or magnesium for PMS, but not premenstrual dysphoric disorder or premenstrual exacerbation.

Don’t just put up with it

The lingering stigma surrounding discussions about periods and menstrual health still leads many women to feel like they must just put up with their symptoms or worry that their experiences aren’t “bad enough” to warrant discussion. This results in unnecessary suffering.

Even when women notice these symptoms, convincing health care practitioners can be challenging, as the link between menstrual hormone fluctuations and mental health is poorly understood.

It’s crucial women are able to discuss these issues openly and are empowered to get the help they need.