Depression is a serious illness. Health professionals use the words depression, depressive illness or clinical depression to refer to it. It is very different from the common experience of feeling unhappy, miserable or fed up for a short period of time.

When you are depressed, you may have feelings of extreme sadness that can last for a long time. These feelings are severe enough to interfere with your daily life, and can last for weeks or months, rather than days.

Depression is quite common and about one in ten people will experience depression at some point. However, the exact number of people with depression is hard to estimate because many people do not get help or are not formally diagnosed with the condition.

Women are more likely to have depression than men, and 1 in 4 women will require treatment for depression at some point, compared to 1 in 10 men. Men are more likely than women to die by suicide, which may be because men are less likely to seek help for depression. Alternatively, it may be due to other factors including substance misuse, unemployment and social isolation.

Depression can affect people of any age, including children. According to Aware, a voluntary organisation which supports people with depression 300,000 people in Ireland suffer from depression.

People with a family history of depression are more likely to experience depression themselves. Depression affects people in many ways and can cause a wide variety of physical, psychological (mental) and social symptoms.

A few people still think that depression is not a real illness and that it is a form of weakness or admission of failure. This is simply not true. Depression is a real illness with real effects, and it is certainly not a sign of failure.

With the right treatment and support, most people can make a full recovery from depression. It is important to seek help from your GP if you think you may be depressed.

The symptoms of depression can be complex. If you are depressed, you often lose interest in things you used to enjoy. Depression commonly interferes with your work, social life and family life. There are many other symptoms, which can be psychological, physical and social.

Psychological symptoms include:

  • continuous low mood or sadness
  • feelings of hopelessness and helplessness 
  • low self-esteem 
  • tearfulness
  • feelings of guilt
  • feeling irritable and intolerant of others 
  • lack of motivation and little interest in things
  • difficulty making decisions
  • lack of enjoyment
  • suicidal thoughts or thoughts of harming yourself
  • feeling anxious or worried 
  • reduced sex drive

Physical symptoms include:

  • slowed movement or speech
  • change in appetite or weight (usually decreased, but sometimes increased)
  • constipation 
  • unexplained aches and pains
  • lack of energy or lack of interest in sex
  • changes to the menstrual cycle
  • disturbed sleep patterns (for example, problems going to sleep or waking in the early hours of the morning)

Social symptoms include:

  • not doing well at work
  • taking part in fewer social activities and avoiding contact with friends
  • reduced hobbies and interests
  • difficulties in home and family life

It can take some time to recognise that you may be depressed. Depression may come on gradually and some people continue to deal with the symptoms without recognising them. It can take a friend or family member to suggest that something is wrong.

Doctors describe depression by how serious it is

  • Mild depression has some impact on your daily life.
  • Moderate depression has a significant impact on your daily life.
  • Severe depression makes the activities of daily life nearly impossible. A small proportion of people with severe depression may have psychotic symptoms.

Grief and depression

Even though grief and depression share many of the same characteristics, there are important differences between them. Grief is an entirely natural response to a loss, while depression is an illness. However, sometimes it can be hard to distinguish between feelings of grief and depression.

People who are grieving find that feelings of loss and sadness come and go, but they are still able to enjoy things and look forward to the future. However, people who are depressed have a constant feeling of sadness. They do not enjoy anything and have little sense of a positive future.

Other types of depression

There are several different types of depression, and some conditions where depression may be a major symptom.

These include:

  • Postnatal depression. Some women develop depression after having a baby. Postnatal depression is treated in similar ways to other forms of depression, with talking therapies and antidepressant medicines.
  • Bipolar disorder is also known as 'manic depression'. It is where there are periods of depression and also periods of excessively high mood (mania). The depression symptoms are similar to clinical depression, but the periods of mania can include harmful behaviour where there are few or no inhibitions, such as gambling to a harmful extent, going on spending sprees and having unsafe sex. 
  • Seasonal affective disorder (SAD). Also known as 'winter depression', SAD is a type of depression that has a seasonal pattern usually related to winter.

There is no single cause of depression, and people develop depression for different reasons.

Depression has many different triggers. For some people, upsetting or stressful life events, such as bereavement, divorce, illness, redundancy and job or money worries, can be the cause. Usually, different causes combine to trigger depression. For example, you may feel low after an illness and then experience a stressful life event, such as bereavement, which leads to depression.

People often talk about a 'downward spiral' of events that leads to depression. For example, if a person's relationship with their partner breaks down, they are likely to feel low, they may stop seeing friends and family, and they may start drinking more. All of this can make them feel even worse and trigger depression.

Some studies have suggested people are more likely to get depression as they get older and that it is more common among people who face difficult social and economic circumstances.

Depression is complex and a number of things can increase the risk of developing it.

Stressful life events

Most people take time to come to terms with stressful events, such as bereavement or a relationship breakdown. When these stressful events happen, you have a higher risk of becoming depressed if you stop seeing friends and family and try to deal with problems on your own.


You may have a higher risk of depression if you are diagnosed with a chronic or life-threatening illness, such as coronary heart disease or cancer.

Head injuries are also an often under-recognised cause of depression. A severe head injury can trigger mood swings and emotional problems.

Even a minor head injury can damage the pituitary gland, which is a pea-sized gland at the base of the brain that produces thyroid-stimulating hormones (chemicals). This can cause a number of symptoms, such as fatigue (extreme tiredness) and a decreased interest in sex, which can lead to depression. 

Personality traits

You may be vulnerable to depression due to certain personality traits, such as low self-esteem or being overly self-critical. This may be due to genes you have inherited from your parents, or your personality or early life experiences. These can all have a profound effect on the way you think about yourself in later life.

Family history of depression

Research shows that some genes increase the risk of depression after a stressful life event.

Giving birth

Some women are particularly vulnerable to depression after pregnancy. The hormonal and physical changes, as well as the added responsibility of a new life, can lead to postnatal depression.

Social isolation

Becoming cut off from family and friends may increase your risk of depression, or it may be a response to feeling depressed as the downward spiral takes hold.

Alcohol and drugs

Substance abuse can be a cause of depression. Use of drugs, such as cannabis and cocaine, can also lead to feelings of depression. Some people try to cope by drinking too much alcohol or taking drugs. This can result in a spiral of depression. The isolation, alcohol or drugs make you feel worse about yourself, and in response you isolate yourself and drink or take drugs even more.


See your GP if you think you have depression. Your GP may give you a physical examination and do some blood or urine tests to rule out other conditions that have similar symptoms, such as underactive thyroid.

There are no physical tests for depression, so detailed interviews and questionnaires are usually used to make a diagnosis.

Many different questionnaires are used to measure depression. However, two classifications of mental illness are most widely used:

  • Diagnostic and Statistical Manual of Mental Disorders. This is a classification system based on all the known recorded symptoms associated with a particular mental condition. Your GP will ask you if you have certain symptoms and, depending on your answers, will be able to use the system to identify the condition.
  • International Classification of Diseases. This is a similar system of classifications, based on the known symptoms associated with particular diseases. Developed by the World Health Organization, it is a much wider system, covering all diseases (not just mental health). Your GP will ask you about your symptoms in order to classify your condition.

Using one of these two guidelines, your GP can usually diagnose depression, decide which type of depression you have, and rule out other mental health conditions.

Any discussion you have with your GP about your depression will be treated in the strictest of confidence. Your GP will only ever break this rule if there is a significant risk of harm to either yourself or to others, and if informing a family member or carer would reduce that risk.


Blood test
During a blood test, a sample of blood is taken from a vein using a needle, so it can be examined in a laboratory.
Urine tests
Urinalysis or UA is when a urine sample is tested, commonly to check for any signs of infection, or protein or sugar levels.

Treatment overview

Treatment for depression usually involves a combination of drugs, talking therapies and self help. Treatment is based on the type of depression you have.

Mild depression

If you are diagnosed with mild depression, it may improve by itself. In this case, you will have another assessment after two weeks to monitor your progress. This is known as watchful waiting.

Antidepressants are not usually recommended as a first treatment for mild depression. 

Exercise seems to help some people. While your progress is being monitored, your GP may refer you to a qualified fitness trainer for an exercise scheme.

Talking through your feelings may also be helpful. You may wish to talk to a friend or relative, or your GP may suggest a local self-help group.

Your GP may recommend self-help books and computerised cognitive behavioural therapy (CBT). See below for further details.

Chronic mild depression (which is present for two years or more) is called dysthymia. This is more common in people over 55 years old and can be difficult to treat. If you are diagnosed with dysthymia, your GP may suggest that you start a course of antidepressants.

Moderate depression

If you have mild depression that is not improving, or you have moderate depression, your GP may recommend a talking treatment or prescribe an antidepressant (see below for further details).

Severe depression

If you have severe depression, your GP may recommend that you take an antidepressant, together with talking therapy. A combination of an antidepressant and cognitive behavioural therapy (CBT) usually works better than having just one of these treatments.

You may be referred to a mental health team. These teams are usually made up of psychologists, psychiatrists, specialist nurses and occupational therapists. They may provide intensive specialist talking treatments, such as psychotherapy.

Talking treatments

Cognitive behavioural therapy (CBT)

(Cognitive behavioural therapy CBT) helps you understand your current thoughts and behaviours and how they affect you. While CBT recognises that events in your past may have shaped you, it concentrates mostly on how you can change the way you think, feel and behave in the present. It teaches you to behave in ways that challenge negative thoughts, for example being active to challenge feelings of hopelessness.

You normally have a fixed number of sessions, usually six to eight sessions over 10-12 weeks. In some cases, you may be offered group CBT.

Computerised cognitive behavioural therapy (CCBT)

Computerised CBT is a form of CBT that works through a computer screen, rather than face to face with a therapist. It is delivered in a series of weekly sessions and should be supported by a healthcare professional. Ask your GP about what is available.

Interpersonal therapy (IPT)

IPT focuses on your relationships with other people and on problems, such as difficulties with communication or coping with bereavement. There is some evidence that IPT can be as effective as medication or CBT, but more research is needed.


Counselling is a form of therapy that helps you think about the problems you are experiencing in your life to find new ways of dealing with them. Counsellors support you in finding solutions to problems, but do not tell you what to do.


Antidepressants are medicines that treat the symptoms of depression. There are almost 30 different kinds of antidepressant, which fall into four main categories.

Most people with moderate or severe depression benefit from antidepressants, but not everybody does. Some people respond to one antidepressant, but not to another, and people with depression may need to try two or more treatments before they find one that works for them.

The different types of antidepressant work about as well as each other. However, side effects vary between different treatments and people.

Normally, you will take only one type of antidepressant at a time, but specialists in mental health (including some GPs) may add other treatments to antidepressants.

Your GP or specialist nurse should see you every one to two weeks when you start taking antidepressants. You should continue taking the antidepressants for at least four weeks (six weeks if you are elderly) to see how well they are working. If your antidepressants are working, treatment should be continued at the same dose for at least four to six months (12 months if you are elderly) after your symptoms have eased. If you have a history of depression, you should continue to receive antidepressants for up to five years or longer.

Antidepressants are not addictive, but withdrawal symptoms are quite common if you stop taking them suddenly or you miss a dose.

Selective serotonin reuptake inhibitors (SSRIs)

If your GP thinks you would benefit from taking an antidepressant, you will usually be prescribed a selective serotonin reuptake inhibitor (SSRI). These help increase the level of a natural chemical in your brain called serotonin, which is thought to be a 'good mood' chemical.

SSRIs are as effective as older antidepressants (TCAs or tricyclic antidepressants) and have fewer side effects. For example, they are less likely to cause drowsiness and dizziness. They can, however, cause nausea and headaches, as well as dry mouth and problems with sexual functioning. However, these usually improve over time.

Examples of this type of antidepressant include sertraline, paroxetine, fluoxetine, citalopram, escitalopram and fluvoxamine.

Some SSRIs should not be prescribed for children under the age of 18. Research shows that the risk of self-harm and suicidal behaviour may increase if they are used to treat depression in people in this age range. Fluoxetine is the only SSRI that may be prescribed for under-18s, but only when specialist advice has been given.

Tricyclic antidepressants (TCAs)

This group of antidepressants, which includes dothiepin, imipramine and amitriptyline, is used to treat moderate to severe depression.

TCAs work by raising the levels of the chemicals serotonin and noradrenaline in your brain. These both help lift your mood. Do not smoke cannabis if you are taking TCAs because it can cause your heart to beat rapidly.

Side effects of TCAs, which vary from person to person, may include dry mouth, blurred vision, constipation, problems passing urine, sweating, light-headedness and excessive drowsiness. The side effects should ease after 7 to 10 days, as your body gets used to the medication.

Monoamine oxidase inhibitors (MAOIs)

MAOIs, such as phenelzine sulphate, are sometimes used to treat depression.

If you are taking MAOIs, you will have to avoid food that contains the chemical tyramine. This is normally found in foods that have been fermented or cured to increase their flavour, such as cheese, pickled meat or fish. Your GP will give you a list of food and drink to avoid.

Do not drink any alcohol or fermented liquids (even if they are alcohol free). Do not smoke cannabis if you are taking MAOIs because it may affect the way these medicines work, and it is not clear what effect this may have on you.

As MAOIs have the potential to interact with a wide range of medication, do not take any other drug or medicine, including over-the-counter medication, without checking with your GP first.

Common side effects of MAOIs include blurred vision, dizziness, drowsiness, increased appetite, nausea, restlessness, shaking or trembling, and difficulty sleeping.

There have been a number of cases where MAOIs have caused a dangerous rise in blood pressure.

If you experience a stiff neck, severe headache, chest pains, vomiting or nausea, or a fast heartbeat, seek emergency help immediately by dialling 999 and asking for an ambulance.

The dietary restrictions and potential for side effects mean that MAOIs are used very rarely, and are normally only prescribed when other treatments have not been effective.

Other antidepressants

New antidepressants, such as venlafaxine, nefazodone and mirtazapine, work in a slightly different way from SSRIs and TCAs. These drugs are known as SNRIs (Serotonin-norepinephrine reuptake inhibitors). Like TCAs, these antidepressants change the levels of serotonin and noradrenaline in your brain. Studies have shown that an SNRI such as venlafaxine can be more effective than an SSRI, though it is not routinely prescribed as it can lead to a rise in blood pressure.

Other treatments

St John's wort

St John's wort is a herbal treatment that some people take for depression. Though there is some evidence that it may be of benefit in treating mild or moderate depression, its use is not recommended. This is because the quantity of its active ingredients varies among individual brands and batches, so it is unclear what sort of effect it could have on you. Side effects of St John's wort include nausea, dizziness and a dry mouth.

Taking St John's wort with other medications, such as anticonvulsants, anticoagulants, antidepressants and the contraceptive pill, can also cause serious problems.

You should not use St John's wort if you are pregnant or breastfeeding as there is not enough evidence that its use is safe in these situations.

Electroconvulsive therapy (ECT)

Sometimes, other treatments, such as specialist medicines or electroconvulsive therapy (ECT), may be advised if you have severe depression. Electroconvulsive therapy (ECT) works for severe depression, but it is only used when antidepressants and other treatments have not worked.

If ECT is recommended for you, you will first be given an anaesthetic and medication to relax your muscles. You will then receive an electrical 'shock' to your brain through electrodes placed on your head. You may be given a series of ECT sessions. It is usually given twice a week for 3-6 weeks. For most people, the treatment works well in relieving severe depression, but the effect may not be permanent. Some people may experience unpleasant side effects, including short-term headaches, memory problems, nausea and muscle aches.


If you have tried several different antidepressants and have experienced no improvement, your doctor may offer you a type of medication called lithium, in addition to your current treatment.

There are two types of lithium: lithium carbonate and lithium citrate. Both are usually effective, but if you are taking one that is effective, it is best not to change. In order for lithium to work, you have to have a certain level of it in your blood. If this level becomes too high, the lithium can become toxic. Therefore, you will need blood tests every three months to check your lithium levels. Avoid eating a low-salt diet because this can also cause the lithium to become toxic. Ask your GP for advice about your diet.

Before you start taking lithium, you should have an electrocardiogram (ECG) to check your heart.

Withdrawal symptoms

Antidepressants are not addictive in the same way that illegal drugs are, but when you stop taking them you may have some withdrawal symptoms, including:

  • upset stomach
  • flu-like symptoms
  • anxiety
  • dizziness
  • vivid dreams at night
  • sensations in the body that feel like electric shocks

In most cases, these effects are mild. However, for a small number of people, they can be quite severe. They seem to be most likely to occur with paroxetine (Seroxat) and venlafaxine (Effexor).

Talking about it

Sharing a problem with someone else or with a group can give you support and an insight into your own depression. Research shows that talking can help people recover from depression and manage stress and periods of difficulty.

You may not feel comfortable about discussing your mental health and sharing your distress with others. Writing about how you feel or expressing your emotions through poetry or art are other ways to help your mood. .

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Avoid drugs and too much alcohol

It may be tempting to use cigarettes or alcohol to make you feel better. They may seem to help at first, but smoking or drinking too much will make things worse in the long run.

Many people see cannabis as harmless, but research has identified a strong link between cannabis use and mental illness, including depression.

The nature of the evidence means that it is not possible to say for sure that cannabis is or is not a cause of depression. For example, people who are depressed may smoke more cannabis than those who are not, or there may be an unidentified reason why some people become both depressed and more likely to smoke cannabis. However, overall the evidence shows that if you smoke cannabis you:

  • make your depression symptoms worse
  • feel more tired and uninterested in things
  • are more likely to have depression that relapses earlier and more frequently
  • will not have as good a response to antidepressant medicines
  • are more likely to stop using antidepressant medicines
  • are less likely to recover fully

If you drink too much or use drugs, get advice and support from your GP or your local drugs and alcohol service.

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If your depression is caused by working too much or is affecting your ability to do your job, you may need a little time off to recover. However, there is evidence that taking prolonged time off work can make depression worse. There is also quite a lot of evidence that going back to work can help you recover from depression.

It is important to avoid too much stress and this includes work-related stress. If you are employed, you may be able to work shorter hours or work in a more flexible way, particularly if job pressures play a role in episodes of symptoms. The Disability Act 2005 imposes significant obligations on government departments and public bodies to improve the quality of life people with disabilitiy. This can include people with a diagnosis of mental illness.

Living with or caring for someone with depression

If you have depression, people around you are likely to be affected by your illness. Your relationships and family life may also be put under strain.

If you are caring for someone with depression, you may feel at a loss. Finding a support group and talking to others in a similar situation might help.

If you are having relationship or marriage difficulties, you can contact specialist relationship counsellors who can talk things through with you and your partner.

Men are less likely to ask for help than women and are also more likely to abuse alcohol or drugs when depressed.

Coping with bereavement

Losing someone close to you may be a trigger for your depression. When someone you love dies, you might feel that it's impossible to recover from the emotional blow. However, with time and the right help and support, it is possible to start living your life again.

Depression and suicide

More than 90% of suicide cases are associated with mental disorders, and many of the 500 or so people who commit suicide each year in Ireland suffer from severe depression.

Some of the warning signs that people with depression are considering suicide are:

  • making final arrangements, such as giving away possessions, making a will or saying goodbye to friends
  • talking about death or suicide. This may be a direct statement, such as 'I wish I was dead,' but often depressed people will talk about the subject indirectly, using phrases like 'I think dead people must be happier than us,' or 'Wouldn't it be nice to go to sleep and never wake up.'
  • self-harm, such as cutting their arms or legs, or burning themselves with cigarettes
  • a sudden lifting of mood, which could mean that a person has decided to end their life and feels better because of this decision

If you are feeling suicidal or in the crisis of depression, contact your GP as soon as possible. They will help you.

If you cannot or do not want to contact your GP, call the Samaritans on 1850 60 90 90, 24 hours a day, seven days a week. Alternatively, visit the Samaritans website or email

Helping a suicidal friend or relative

If you see any of the above warning signs:

  • Get professional help for the person.
  • Let them know they are not alone and that you care about them.
  • Offer your support in finding other solutions to their problems.

If you feel that there is an immediate danger, stay with the person or have someone stay with them, and remove all available means of harming themselves, such as medication. Over-the-counter drugs, such as painkillers, can be just as dangerous as prescription medication. Also, remove sharp objects and poisonous household chemicals, such as bleach.

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Content provided by NHS Choices and adapted for Ireland by the Health A-Z.

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