PMS vs PMDD: Symptoms, Causes and How to Tell the Difference

30/08/2020/Zoya Ali BSc, MSc

PMS and PMDD can both occur during the luteal phase of the menstrual cycle. But what is the difference between PMS and PMDD and what are the treatments available? Read on to find out.

Quick facts:

PMS affects up to 90% of people who menstruate
PMDD is a more severe, clinical condition, affecting around 3–8%
Both occur in the luteal phase (after ovulation, before your period)
There are treatments available to elevate symptoms, including speaking to a mental health professional.

What is Premenstrual Syndrome (PMS)?

Premenstrual Syndrome (PMS) refers to a group of physical, emotional, and behavioural symptoms that occur in the days or weeks leading up to your period. For many people, PMS is a familiar but manageable part of the menstrual cycle, with up to 90% of women and people who menstruate experiencing it at some point.

PMS can vary from person to person, with some people just experiencing mild symptoms, with others suffering from more extreme symptoms that can affect their daily lives.

What are the most common symptoms of PMS?

There are a combination of physical and mental symptoms that can be associated with PMS. Some of the most common symptoms include:

Mood swings
Feeling upset, anxious or irritable
Fatigue
Trouble sleeping
Bloating and digestive issues
Food cravings
Abdominal pain
Lower back pain
Breast tenderness
Headaches
Acne flare-ups or breakouts
Oily skin
Greasy hair
Changes in appetite

What is PMDD?

Premenstrual Dysphoric Disorder (PMDD) is a cyclical hormone-based mood disorder. that affects mood, behaviour, and physical wellbeing in the days leading up to your period.

While PMS exists on a spectrum, PMDD sits at the most severe end. What makes PMDD distinct is not just the symptoms themselves, but how disruptive they can be. People often describe feeling like a completely different version of themselves in the second half of their cycle, with changes that affect their ability to work, maintain relationships, or carry out daily routines.

These symptoms follow a clear cyclical pattern, typically emerging after ovulation, intensifying in the week before a period, and easing shortly after menstruation begins. This predictable timing is one of the most important clinical clues and one of the reasons PMDD is often misunderstood or missed altogether.

PMDD is estimated to affect up to 5.5% of the population in the UK who menstruate, which adds up to over a million. That is 1 in 20 people.

What Are the Main Symptoms of PMDD?

PMDD can present a wide range of emotional, physical, and cognitive symptoms. The main symptoms of PMDD include severe mood swings, irritability or anger, anxiety, depression, and difficulty concentrating. Many people also experience physical symptoms such as fatigue, bloating, sleep disturbances, and appetite changes.

Symptoms occur in the luteal phase or premenstrual phase of the menstrual cycle and subside within a few days of menstruation due to the brain’s sensitivity to the natural rise and fall of progesterone and oestrogen. Recognising these patterns is key to understanding whether what you’re experiencing could be PMDD.

🌪 Emotional & Mood Changes

Mood swings (sudden, intense emotional changes from extreme highs to deep lows)
Irritability or anger (often disproportionate to the situation, may strain relationships)
Crying spells
Anxiety or tension
Depression or hopelessness
Highly Sensitive
Low self-esteem / Feelings of Inadequacy
Paranoia or irrational thinking
Panic attacks
Feelings of sadness or despair, or even thoughts of suicide
Tiredness or low energy
Low sex drive

🧠 Cognitive & Psychological

Brain fog
Delusions
Depersonalization (Emotionally Disconnected)
Derealization (Feels the World is Distorted)
Loss of interest in usual activities
Difficulty concentrating (trouble focusing or maintaining attention)
Mutism (Unable or Unwilling to Speak)
Misophonia (Strong Reaction to Sound)
Feeling out of control

🛌 Physical & Sensory Symptoms

Bloating
Fatigue
Breast tenderness
Changes in sleep patterns (difficulty falling or staying asleep)
Appetite changes (increased cravings or changes in eating habits)
Painful periods
Numbness or heightened sensitivity in limbs
Acne and/or sensitive skin
Hot flushes and night sweats
Pelvic pain
Muscle and Joint Pain
Heart palpitations
Vision changes
Decreased coordination and/or dizziness

In the most severe cases of PMDD, some people may experience suicidal ideation or suicidal thoughts. If you need urgent help for your mental health you can contact the Samaritans 24/7 helpline, or Mind’s crisis resources.

What Does PMDD Actually Feel Like?

PMDD is often characterised by a shift in emotional and psychological state that can feel difficult to control or explain. Unlike PMS, where symptoms may feel uncomfortable but manageable, PMDD can feel overwhelming and, at times, debilitating.

Many people report intense mood changes, including persistent low mood, anxiety, irritability, or a sense of being emotionally overwhelmed. There can be a loss of interest in things that would usually bring enjoyment, alongside difficulty concentrating or making decisions. For some, these changes are accompanied by intrusive or distressing thoughts, and in more severe cases, feelings of hopelessness or suicidal ideation, which is why PMDD is recognised as a serious medical condition.

Importantly, these symptoms are cyclical. They tend to resolve once the period starts, sometimes quite suddenly, which can make the contrast between phases of the cycle feel even more pronounced.

It’s also important to note that PMDD can occur even in people who do not bleed regularly. For example, individuals using a hormonal coil or those who have had a hysterectomy but still have functioning ovaries may still experience PMDD symptoms, as hormonal cycling continues.

What Causes PMDD?

PMDD is often misunderstood as a hormonal imbalance, but current research suggests something more nuanced. Most people with PMDD have hormone levels that fall within the typical range. Instead, the condition appears to be driven by an increased sensitivity in the brain to the normal hormonal changes especially linked to oestrogen and progesterone that occur across the menstrual cycle, particularly after ovulation.

There is also evidence to suggest a genetic component. Individuals with PMDD are more likely to have a family history of the condition, as well as mood disorders such as depression or anxiety.Variations in genes involved in hormone regulation and serotonin signalling may increase susceptibility, helping to explain why some people experience more severe reactions to hormonal shifts than others.

Emerging research and lived experience also point towards a potential link between PMDD and neurodiversity. Some neurodivergent individuals, including those who are autistic, report more intense or difficult-to-manage symptoms. This may be related to differences in how the nervous system processes stress, sensory input, and emotional change. It is important to note that neurodiversity does not cause PMDD, but it may influence how symptoms are experienced and perceived.

Stress is another key factor. Chronic stress can disrupt the body’s hormonal and neurological balance, particularly through its effects on cortisol, the primary stress hormone. This may amplify sensitivity to normal hormonal fluctuations and worsen the emotional and physical symptoms associated with PMDD.

Mental health history also plays an important role. Individuals with a history of trauma, anxiety, or depression may be more vulnerable to PMDD, and symptoms can often overlap or intensify during certain phases of the cycle. This does not mean PMDD is purely psychological, but rather that it sits at the intersection of hormonal and mental health processes.

Beyond the brain and hormones, there is growing interest in the role of inflammation. Some studies have found elevated inflammatory markers in people with PMDD, suggesting that inflammation may interact with hormonal sensitivity and contribute to symptoms such as fatigue, low mood, and brain fog.

Nutritional status may also influence symptom severity. Deficiencies in key nutrients such as magnesium, calcium, and vitamin D have been associated with more severe symptoms. These nutrients play important roles in neurotransmitter function, hormone regulation, and the body’s ability to manage stress and inflammation.

Finally, the gut–brain axis is an emerging area of research in PMDD. The gut microbiome plays a role in regulating mood, immune function, and inflammation, as well as influencing serotonin production. Disruptions in gut health may increase the body’s reactivity to hormonal changes and contribute to the overall symptom experience.

Taken together, PMDD is best understood as a complex, multi-factorial condition. It is not caused by a single issue, but rather by the interaction between hormonal changes, brain sensitivity, genetics, stress, and broader health factors. This is why experiences of PMDD can vary so widely and why a personalised approach to understanding and managing symptoms is so important.

Can PMDD Be Treated?

The good news is that PMDD is manageable with the right support.

Treatment may include a combination of lifestyle changes, psychological therapies such as CBT, and medical options including SSRIs or hormonal treatments. The most effective approach will vary from person to person.

If you don’t already, tracking your symptoms and cycle to see if there’s a correlation between when your symptoms are appearing and where you’re at in your cycle can really help.

You can track your cycle using a cycle-tracking app, or simply keep a record of it on a calendar. Once you’ve deciphered any patterns with your symptoms appearing, it can become easier to anticipate when they’ll appear. This can allow you to have more control over planning your schedule around them and factoring in self-care.

If your experience of severe PMS or PMDD symptoms is regularly affecting your wellbeing, it can be extremely beneficial to talk to a professional. The idea of diagnosing a mental health disorder can be daunting, but it is the first and most important move in alleviating your suffering.

Support for PMDD

PMDD can feel isolating, especially when symptoms are dismissed or misunderstood. Connecting with others who understand what you’re going through can make a real difference.

You may find support through:

The PMDD Project – education, resources, and community support
IAPMD (International Association for Premenstrual Disorders) – global support network and peer groups
Mind (UK) – mental health support and information
NHS resources – guidance on symptoms, diagnosis, and treatment

These organisations offer a mix of education, peer support, and practical tools to help you navigate PMDD.

If You’re Struggling Right Now

PMDD can sometimes involve intense emotional distress, including feelings of hopelessness or suicidal thoughts. If you’re feeling this way, it’s important to know that support is available and you don’t have to go through it alone.

If you are in the UK, you can contact:

Samaritans (24/7): 116 123
Shout (text support): Text “SHOUT” to 85258
NHS 111 if you need urgent mental health support

If you are in the Ireland, you can contact:

Call Samaritans 116 123
Pieta House – Call 1800 247 247 (24/7 support )
Aware – Aware offers support for people experiencing depression or anxiety. You can call their helpline at 1800 80 48 48 or email support@aware.ie for assistance.

If you are outside the UK, you can find local crisis support services here:
👉 https://www.iasp.info/resources/Crisis_Centres/

If you feel in immediate danger, please call your local emergency services.

How Hertility Can Support You

If you’re experiencing symptoms that feel intense, cyclical, or difficult to explain, understanding your body is an important first step.

While PMDD itself isn’t diagnosed through a blood test, understanding your hormone patterns alongside symptom tracking can help you identify trends and rule out other conditions such as hormone imbalances or thyroid disorder.

Our reports are designed to give you practical, personalised guidance, so you’re not left trying to make sense of your symptoms alone.

FAQs About PMS and PMDD

How do I know if I have PMDD or PMS?

If your symptoms are severe, affect your ability to function, and follow a consistent pattern before your period, it may be PMDD rather than PMS. Tracking your symptoms across at least two menstrual cycles can help identify this pattern.

What’s the Difference Between PMS and PMDD?

Premenstrual Syndrome (PMS) and Premenstrual Dysphoric Disorder (PMDD) are both linked to the menstrual cycle, but they differ in severity and impact.

PMS is common and usually causes mild to moderate physical and emotional symptoms that do not significantly interfere with daily life. PMDD is a severe, clinically recognised condition that causes intense mood changes, anxiety, and depression in the luteal phase of the cycle, often affecting work, relationships, and overall functioning.

Can PMDD be diagnosed with a blood test?

No, PMdd cannot be diagnosed through blood, hormone, or saliva tests. While these tests can help rule out other underlying conditions, such as hormone imbalances or thyroid disorders, they cannot confirm a diagnosis. The only current method for diagnosing PMDD is by tracking symptoms daily throughout at least two menstrual cycles.

Why do I feel depressed before my period?

Hormonal changes after ovulation can affect brain chemicals such as serotonin and GABA. In people with PMDD, the body is thought to be more sensitive to these changes, which can lead to symptoms such as low mood, anxiety, and irritability.

Is PMDD a mental health condition or a hormonal condition?

PMDD is best understood as a neuro-hormonal condition. It involves how the brain responds to normal hormonal changes, rather than a simple hormone imbalance.

What is the difference between PMDD and PME?

PMDD is not the same as Premenstrual Exacerbation (PME), although the two are often confused.

PMDD refers to symptoms that are specifically tied to the menstrual cycle, appearing in the luteal phase and improving after menstruation begins.

PME, on the other hand, occurs when an existing condition such as depression, anxiety, ADHD, autism, or bipolar disorder worsens before a period but does not fully resolve afterwards.

Both conditions are valid and require support, but distinguishing between them is important for choosing the right treatment approach.

Can PMDD be treated?

Yes, PMDD can be managed with the right support. Treatment options may include lifestyle changes, therapy, and medical treatments such as SSRIs or hormonal therapies.

Resources:

Mental Health periods PMDD PMS

Zoya Ali BSc, MSc

Zoya is a scientific researcher with a Bachelor's degree in Biotechnology and a Masters in Prenatal Genetics & Foetal Medicine from University College London. Her research interests are reproductive genetics, fertility preservation, gynaecological health conditions and sexual health.

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