PMS & PMDD (Premenstrual Syndrome / Dysphoric Disorder)
Tearful, irritable, bloated or anxious in the days before your period — then fine once it starts? That cyclical pattern is PMS, and its more severe form, PMDD, is a recognised condition you don't have to just endure.
Up to 3 in 4 menstruating women experience some PMS; about 1 in 20 have the more severe PMDD— ACOG / international gynaecology estimates
Up to 3 in 4 menstruating women experience some PMS; about 1 in 20 have the more severe PMDD— ACOG / international gynaecology estimates
General education, not a diagnosis. SHELY is pre-launch — “Talk to someone” adds you to our experts waitlist; we don’t offer bookings yet.
Premenstrual syndrome (PMS) is a cluster of physical and emotional symptoms that show up in the luteal phase — the week or two after ovulation and before your period — and ease off once bleeding begins. The defining feature isn't any single symptom but the timing: the same complaints arrive on a predictable monthly rhythm and lift within a few days of your period starting.
Premenstrual dysphoric disorder (PMDD) is PMS's severe sibling. It's a recognised mood condition — listed in the DSM-5 — where the emotional symptoms (deep sadness, hopelessness, irritability, or feeling out of control) become intense enough to disrupt work, relationships, and daily life. PMDD is not 'just bad PMS' or a character flaw; it reflects an unusually sensitive brain response to the normal hormone shifts of your cycle.
Both are real and treatable. Tracking your symptoms across two or three cycles is the single most useful step — it confirms the cyclical pattern, rules out conditions that run all month, and gives a clinician what they need to help.
Signs & symptoms
- Mood swings, tearfulness, or sudden irritability in the days before your period
- Anxiety, tension, or feeling on edge
- Low mood or, in PMDD, deep sadness and hopelessness
- Bloating, breast tenderness, and water retention
- Headaches or worsening migraines premenstrually
- Fatigue and disrupted sleep (too much or too little)
- Food cravings, especially for carbs or sweets
- Trouble concentrating or feeling overwhelmed
- Symptoms that reliably ease within a few days of your period starting
Types
PMS (Premenstrual Syndrome)
Mild-to-moderate physical and emotional symptoms in the luteal phase that are bothersome but don't severely disrupt daily life.
PMDD (Premenstrual Dysphoric Disorder)
A severe, DSM-5-recognised form where mood symptoms — irritability, despair, or feeling out of control — significantly impair work, relationships, or functioning.
PME (Premenstrual Exacerbation)
When an existing condition such as depression, anxiety, or migraine flares up in the premenstrual phase rather than starting fresh each cycle.
What causes it
- Sensitivity to the normal rise and fall of progesterone and oestrogen after ovulation
- Changes in serotonin, the brain chemical that steadies mood (why SSRIs help PMDD)
- An exaggerated brain response to allopregnanolone, a progesterone breakdown product
- A personal or family history of depression, anxiety, or PMDD
- Stress, poor sleep, and high caffeine or alcohol intake, which amplify symptoms
When to seek help
See a doctor if premenstrual symptoms are disrupting your work, studies, or relationships, if low mood or irritability feel unmanageable, or if symptoms don't lift after your period starts (which may point to something other than PMS). Seek help urgently — or use crisis support — if you ever have thoughts of harming yourself; PMDD can bring intense, time-limited despair, and this is treatable.
How SHELY helps
SHELY Care
Log mood and symptoms daily — over two or three cycles the app reveals the luteal-phase pattern that confirms PMS or PMDD.
Symptom Checker
Map what you're feeling and when, so you can tell cyclical premenstrual symptoms apart from all-month conditions.
SHELY Varsity
Plain-language guides on managing PMS and PMDD — from sleep and nutrition to when an SSRI or hormonal option may help.
Crisis Support
If PMDD brings overwhelming despair or thoughts of self-harm, find immediate help and someone to talk to.
Not sure what comes next?
Pick a topic to explore what we know about PMS & PMDD (Premenstrual Syndrome / Dysphoric Disorder). Educational only — not a diagnosis.
- Mood swings, tearfulness, or sudden irritability in the days before your period
- Anxiety, tension, or feeling on edge
- Low mood or, in PMDD, deep sadness and hopelessness
- Bloating, breast tenderness, and water retention
- Headaches or worsening migraines premenstrually
- Fatigue and disrupted sleep (too much or too little)
- Food cravings, especially for carbs or sweets
- Trouble concentrating or feeling overwhelmed
- Symptoms that reliably ease within a few days of your period starting
- Sensitivity to the normal rise and fall of progesterone and oestrogen after ovulation
- Changes in serotonin, the brain chemical that steadies mood (why SSRIs help PMDD)
- An exaggerated brain response to allopregnanolone, a progesterone breakdown product
- A personal or family history of depression, anxiety, or PMDD
- Stress, poor sleep, and high caffeine or alcohol intake, which amplify symptoms
PMS (Premenstrual Syndrome)
Mild-to-moderate physical and emotional symptoms in the luteal phase that are bothersome but don't severely disrupt daily life.
PMDD (Premenstrual Dysphoric Disorder)
A severe, DSM-5-recognised form where mood symptoms — irritability, despair, or feeling out of control — significantly impair work, relationships, or functioning.
PME (Premenstrual Exacerbation)
When an existing condition such as depression, anxiety, or migraine flares up in the premenstrual phase rather than starting fresh each cycle.
See a doctor if premenstrual symptoms are disrupting your work, studies, or relationships, if low mood or irritability feel unmanageable, or if symptoms don't lift after your period starts (which may point to something other than PMS). Seek help urgently — or use crisis support — if you ever have thoughts of harming yourself; PMDD can bring intense, time-limited despair, and this is treatable.
SHELY Care
Log mood and symptoms daily — over two or three cycles the app reveals the luteal-phase pattern that confirms PMS or PMDD.
Symptom Checker
Map what you're feeling and when, so you can tell cyclical premenstrual symptoms apart from all-month conditions.
SHELY Varsity
Plain-language guides on managing PMS and PMDD — from sleep and nutrition to when an SSRI or hormonal option may help.
Crisis Support
If PMDD brings overwhelming despair or thoughts of self-harm, find immediate help and someone to talk to.
Symptoms
- Mood swings, tearfulness, or sudden irritability in the days before your period
- Anxiety, tension, or feeling on edge
- Low mood or, in PMDD, deep sadness and hopelessness
- Bloating, breast tenderness, and water retention
- Headaches or worsening migraines premenstrually
- Fatigue and disrupted sleep (too much or too little)
- Food cravings, especially for carbs or sweets
- Trouble concentrating or feeling overwhelmed
- Symptoms that reliably ease within a few days of your period starting
Causes
- Sensitivity to the normal rise and fall of progesterone and oestrogen after ovulation
- Changes in serotonin, the brain chemical that steadies mood (why SSRIs help PMDD)
- An exaggerated brain response to allopregnanolone, a progesterone breakdown product
- A personal or family history of depression, anxiety, or PMDD
- Stress, poor sleep, and high caffeine or alcohol intake, which amplify symptoms
Types
PMS (Premenstrual Syndrome)
Mild-to-moderate physical and emotional symptoms in the luteal phase that are bothersome but don't severely disrupt daily life.
PMDD (Premenstrual Dysphoric Disorder)
A severe, DSM-5-recognised form where mood symptoms — irritability, despair, or feeling out of control — significantly impair work, relationships, or functioning.
PME (Premenstrual Exacerbation)
When an existing condition such as depression, anxiety, or migraine flares up in the premenstrual phase rather than starting fresh each cycle.
When to seek care
See a doctor if premenstrual symptoms are disrupting your work, studies, or relationships, if low mood or irritability feel unmanageable, or if symptoms don't lift after your period starts (which may point to something other than PMS). Seek help urgently — or use crisis support — if you ever have thoughts of harming yourself; PMDD can bring intense, time-limited despair, and this is treatable.
How SHELY helps
SHELY Care
Log mood and symptoms daily — over two or three cycles the app reveals the luteal-phase pattern that confirms PMS or PMDD.
Symptom Checker
Map what you're feeling and when, so you can tell cyclical premenstrual symptoms apart from all-month conditions.
SHELY Varsity
Plain-language guides on managing PMS and PMDD — from sleep and nutrition to when an SSRI or hormonal option may help.
Crisis Support
If PMDD brings overwhelming despair or thoughts of self-harm, find immediate help and someone to talk to.
Frequently asked
How is PMDD different from PMS?
It's a matter of severity and impact. PMS is bothersome but manageable; PMDD brings intense mood symptoms — despair, rage, or feeling out of control — that genuinely disrupt your life. PMDD is a recognised medical condition, not 'extreme PMS.'
How do I know it's premenstrual and not depression?
Timing is the clue. PMS and PMDD symptoms appear after ovulation and clear within a few days of your period; depression and anxiety run all month. Tracking your mood across two or three cycles is the clearest way to tell them apart.
What actually helps?
A lot. Regular sleep, exercise, and cutting back on caffeine and alcohol ease milder PMS. For PMDD, SSRIs (sometimes taken only in the luteal phase) and certain hormonal options like the combined pill can be very effective — your doctor can guide the right fit.
Is PMDD all in my head?
No. PMDD reflects how your brain responds to normal hormone changes — it's biological, well documented, and treatable. Feeling this way doesn't make you dramatic or weak.
✔ Written from established medical guidance — independent clinical review in progress
This guide is for general education and does not replace professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider about your health. In an emergency or crisis, see our crisis support resources.