Premenstrual syndrome (PMS)

Premenstrual syndrome (PMS) can affect you in the days leading up to your period (menstruation), usually around 5–11 days before your period starts.

While many menstruating women experience symptoms before their period starts, it’s estimated that up to 40% have symptoms significant enough to be described as PMS. Often those around you may know it’s ‘that time of the month’.

On this page, you can find the following information:

Key points about premenstrual syndrome:

  1. PMS is very normal.
  2. Symptoms usually go away by the time you get your period.
  3. The causes of PMS are not fully understood but are likely to be linked to fluctuation of hormone levels in your body.
  4. The effects of PMS are different for everyone.

What causes PMS?

No one knows for sure what causes PMS, but several factors may contribute to it: 

  • Hormone changes:
    • Signs and symptoms of PMS are likely to be linked to hormone levels such as oestrogen and progesterone. These hormonal changes affect women differently and can be further altered by lifestyle, hereditary factors, nutritional status, and your emotional state at the time of PMS symptoms appearing.
  • Chemical changes in the brain:
    • Fluctuations of serotonin, a brain chemical that's thought to play a crucial role in mood states, could trigger PMS symptoms. Low serotonin may contribute to premenstrual depression, as well as to fatigue, food cravings and sleep problems.
  • Depression:
    • Some women with severe premenstrual symptoms may have undiagnosed depression, although depression alone does not cause all of the symptoms of PMS.

Some women have very mild symptoms and others have severe symptoms affecting them for days at a time.

 Image: Canva

What are the symptoms of PMS?

Premenstrual syndrome has a wide variety of signs and symptoms, and you might only experience a few of these. They could include emotional or behaviour changes like:

  • mood swings and irritability or anger
  • food cravings and appetite changes
  • tiredness and trouble falling asleep
  • depressed mood and crying spells
  • changes in libido (sex drive).

Physical signs and symptoms may include:

  • muscle or joint pain
  • headaches
  • general fatigue
  • temporary weight gain
  • bloating (feeling like your tummy/puku is full of air)
  • sore breasts
  • acne and pimple flare-ups
  • constipation (not being able to poo) or diarrhoea (runny poo).

How is PMS diagnosed?

There are no unique tests or lab tests to positively diagnose PMS. Blood tests to check hormone levels are not generally done as the levels are often normal for women with PMS.

To help establish a premenstrual pattern, your doctor may have you record your signs and symptoms on a calendar or in a symptom diary for at least 2 menstrual cycles. Note the day that you first notice any PMS symptoms, as well as the day they disappear. Also be sure to mark the days your period starts and ends.

When should I see my doctor?

If these physical and emotional symptoms start to affect your daily life, or if they don’t go away with lifestyle changes, see your doctor or nurse.

Other conditions such as chronic fatigue syndrome, thyroid disorders or mood disorders like depression and anxiety might share common symptoms. Your health care provider might order extra tests such as a thyroid function test to help provide a clear diagnosis.

How is PMS treated?

Depending on your symptoms your doctor might recommend:

  • antidepressants
  • painkillers – nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen
  • oral contraceptives
  • diuretics
  • hormone therapy.
NOTE: A variation of PMS, known as premenstrual dysphoric syndrome, is characterised by severe symptoms which have a negative impact on a woman's lifestyle and functioning. In worst cases it can lead to suicidal tendencies. If you are feeling very distressed ask for help by calling Healthline free on 0800 611 116 or call/text 1737 to talk to a trained counsellor at no cost. 

Are there any non-prescription alternatives?

Complementary health measures such as vitamins and herbal remedies could be beneficial to women with mild PMS, along with acupuncture, massage, reflexology or yoga.

There's mixed evidence to support the use of supplements. These include:

  • Magnesium
  • Zinc
  • Calcium/Vitamin D 
  • Evening Primrose Oil 
  • Vitamin A 
  • Vitamin E 
  • Vitamin B6 – note that a high dose can be associated with peripheral neuropathy (nerve damage). Please check with your doctor before taking. 

Another option is to get counselling, eg, cognitive behavioural therapy, and seek support. For a busy working woman and/or mum this could be help in the form of a cleaner or babysitter. Just remember, if PMS is a problem for you, there are ways to manage it.

What can I do to look after myself with PMS?

There are things you can do to make yourself feel a bit better:

  • Talk to your whānau and friends about how you are feeling, it will help them to be more understanding if you are having a bad day – physically or emotionally.
  • Decrease your caffeine intake – caffeine can make you more nervous, anxious and irritable. It can also make it hard to sleep. Sources of caffeine are coffee, chocolate, Coca-Cola and some energy drinks. Try decaf coffee and herbal tea or load up on plenty of water instead.
  • Keep an even blood glucose level by eating small, nutritious meals often (every 2–3 hours) and reduce the carbohydrates and starches in your diet. Avoid chocolates and sweets which can cause uneven blood glucose levels.
  • Decrease your salt intake and reduce the amount of alcohol you drink.
  • Try to decrease the amount you smoke – or quit altogether. 
  • Exercise regularly. Exercise helps in a number of ways. A daily walk at least 5 times a week for 30 minutes is relaxing and releases natural antidepressants (endorphins) into the system which, in turn, reduce your stress levels. It also gives you time to think on your own. As a weight-bearing exercise walking will often help to reduce any joint pain you may have.
  • Aim for a good night's sleep.
  • Try to keep stress to a minimum and use relaxation techniques like belly breathing and meditation.

Learn more

Premenstrual syndrome Patient Info, UK
Premenstrual syndrome Family Planning, NZ
Premenstrual syndrome (PMS) – a patient's guide Family Doctor, NZ 


Premenstrual syndrome (PMS) Mayo Clinic, US, 2022
Premenstrual syndrome Family Planning, NZ
Premenstrual syndrome (PMS) – a patient's guide Family Doctor, NZ 
Premenstrual syndrome management (Green-top guideline No. 48) RCOG, UK, 2016

Credits: Health Navigator Editorial Team. Reviewed By: Dr Janice Yin Hoi Lee, GP, Auckland Last reviewed: 30 Aug 2022