What is depression? Symptoms, causes and treatment
Depression? Here I help you get a full picture of depression: what it is, its symptoms, its treatment, and even what you can do at home. The information below is based on reliable sources such as the US National Institute of Mental Health, with no pop psychology. I try to share useful points; this page is also helpful for psychology students, and I always welcome your feedback.
What is depression?
First, let's understand what depression is and how it is defined, so we can tell it apart from other conditions and recognise that not every kind of sadness is depression. Depression is sometimes also called major depression, clinical depression or depressive disorder; the information on this page covers all of these.
Depression is very common and is classed as a mood disorder. It can cause severe symptoms that affect how a person feels and behaves, and it can affect daily activities such as sleeping, eating and working.
The first thing to know about diagnosing depression is that symptoms must last at least two weeks.
To understand the symptoms of depression, it helps to know its types, because depression is not just one condition and the types have somewhat different symptoms.
Types of depression
Here we look at the most common types of depression, based on the DSM-5 diagnostic manual and the US National Institute of Mental Health (NIMH).
Table of types of depression
| Type of depression | Main feature |
|---|---|
| Major depressive disorder | Symptoms of depression most of the day, nearly every day, for at least two weeks, interfering with sleep, eating, work and relationships. |
| Persistent depressive disorder (dysthymia) | Milder but long-lasting symptoms: at least two years in adults and one year in children and teenagers. |
| Perinatal depression | Major depression during pregnancy or after birth. It is different from the "baby blues", which are mild and usually pass within about two weeks. |
| Seasonal depression | Usually starts in autumn and winter and improves in spring and summer. |
| Depression with psychotic features | Severe depression with delusions or hallucinations. |
| Premenstrual dysphoric disorder (PMDD) | Severe mood symptoms in the week before a period that ease once the period starts. |
| Depression in bipolar disorder | Depressive episodes that occur alongside episodes of mania or hypomania. |
A note on types of depression: most people with bipolar disorder also have periods of depression, which is why people sometimes talk about "bipolar depression". During these periods the person feels sad, uninterested and hopeless, with very low energy. The key difference is that bipolar disorder also involves episodes of mania or hypomania: periods of elevated, energised or very irritable mood. These do not occur in major depression, and in DSM-5 bipolar disorder is classified separately from the depressive disorders.
Who gets depressed?
Research shows that depression occurs across all ethnic groups, races and genders. More women are diagnosed with depression, but it is also common in men; the lower numbers in men may partly be because men talk about it less and seek treatment less often. In general, men tend to talk less and put their feelings into words less, so this is not surprising.
Research shows that depression is more common among LGBTQIA+ people; researchers see discrimination and social pressure as one of the main reasons.
Symptoms of depression in women, men, teenagers and children
What are the symptoms of depression? You may have asked yourself, "Am I depressed?" or "Is my daughter or son depressed?"
Depression should be diagnosed by a doctor or mental health professional, but the following are recognised symptoms of depression.
- If you have several of the symptoms below most of the day, nearly every day, for at least two weeks, you may have depression.
- You feel sad or anxious most of the time, or feel empty.
- You feel hopeless and pessimistic.
- You lose your temper easily, or feel helpless and worthless.
- You no longer feel anything for the interests and activities you used to enjoy.
- You feel low in energy, tired and slowed down.
- You have trouble concentrating, making decisions or remembering things.
- You sleep badly, cannot get up in the morning, or sleep too much.
- You have lost your appetite, or your weight has changed without trying.
- You have physical aches such as headaches, cramps or digestive problems with no clear physical cause, or that do not improve with treatment.
- You think a lot about death or suicide, or have attempted suicide.
Not everyone with depression has all of these symptoms; some have a few, while others may have all of them.
Depression disrupts daily life, and the person is constantly struggling with it.
Depression can also cause changes in behaviour, such as:
more anger and irritability, feeling very restless, withdrawing or becoming negative, taking more risks, more impulsive behaviour, drinking more alcohol or using more drugs, pulling away from family and friends, being unable to carry out important tasks, and more sexual problems.
As I said at the start, whether we are men or women, young or old, or even children, we can all become depressed, but the signs of depression can look different in men and women.
For example, men with depression may not seem sad all the time but may be angry or turn to alcohol, and research has shown that men are more likely to use drugs when depressed.
Physical symptoms of depression
Depression can sometimes cause physical problems, such as a racing heart, tightness in the chest, ongoing headaches or digestive problems. Men are more likely to see a doctor about physical problems like these than about emotional ones alone.
Not everyone who dies by suicide is depressed, but because depression increases pessimism and distressing thoughts, the risk of suicide is higher among people with depression.
It is best not to wait until symptoms get worse or last longer, because mild depression responds to treatment faster. If you are reading this page because you, or someone close to you, have many of these symptoms, it is a good time to take a step towards feeling better.
If you are depressed, or keep asking yourself whether you are, talk to a GP, counsellor or psychologist. In Australia, if you are having thoughts of suicide or are in crisis, you can call Lifeline on 13 11 14 at any time of the day or night; in immediate danger, call 000.
Risk factors: what makes depression more likely?
Depression is one of the most common mental health conditions in the world (I could not find accurate figures for depression in Iran, and I would be glad if you could share any). So it is important to know what makes depression more likely.
Researchers believe a combination of genetic, biological, environmental and psychological factors is involved. Risk factors include a personal or family history of depression, major life changes, trauma or severe stress, some physical illnesses and some medicines.
Depression in children and teenagers
Depression can start at any age, even in people with no obvious risk factors, but it often begins in adulthood.
Depression also occurs in children and teenagers; in children it often shows up as aggression and irritability rather than sadness. Interestingly, many chronic mood and anxiety disorders in adults begin as high levels of anxiety in childhood.
Depression in middle and older age
In middle and older age, depression often occurs alongside serious physical illnesses such as diabetes, heart disease, cancer and Parkinson's disease. Depression can make these illnesses worse, and the illnesses also make depression more likely.
For this reason, during the COVID-19 pandemic the US Centers for Disease Control and Prevention (CDC) listed mood disorders such as depression, and schizophrenia, among the conditions that increase the risk of severe COVID-19.
We also take more medicines in middle and older age, and depression can be a side effect of some of them. Always pay attention to side effects, and if you do not have the time or energy to check them all, stay in touch with your doctor, pharmacist or nurse so they can review your medicines.
Risk factors to watch for at this age include a personal or family history of depression, and any major life event or change that has caused stress, such as the death of someone close.
How is depression treated?
Depression is treatable for most people. As I mentioned, the earlier treatment starts, the better the chance of full recovery.
If, like many people, you are searching online for home treatments for depression, I want to keep this discussion evidence-based and cover the treatments as fully as I can. The main treatments for depression are psychotherapy, medication, or a combination of both.
If the first treatment does not work, the doctor may try another medicine or add a second one.
If psychotherapy and medication do not reduce symptoms, brain stimulation treatments such as ECT or TMS are the next option (explained below).
An important point: no two people experience depression in exactly the same way, so there is no one-size-fits-all treatment; working with people with depression makes this very clear, and I ask colleagues to approach it with great care. If you have depression, know that finding the right treatment for you can take time, but with ongoing treatment most people get better.
Medication for depression
If you are looking for herbal or "happy" remedies, I believe it is better to talk to a doctor, who can prescribe what suits you. Still, in this section I review depression medicines as fully as I can.
Antidepressants are very common. In Iran some are sold without a prescription, but taking them without a doctor's advice is dangerous; in Australia they are available only on prescription. Each medicine suits some people better than others, and sometimes the doctor needs to try several, one at a time, to find the best one. Antidepressants are also effective for severe depression.
Often, when we feel depressed, the first medicine we think of is one a relative has used, or one we have taken before. At these times it is important to keep a few things in mind.
Treating severe depression takes time and needs to be continued.
Most antidepressants take about 4 to 8 weeks to work fully. Problems such as sleep, appetite and concentration sometimes improve before mood does.
Antidepressants can have side effects such as nausea, changes in sleep, changes in appetite or weight, and sexual problems. Many of these ease in the first few weeks; if they bother you, do not stop the medicine on your own; talk to your doctor.
Newer antidepressants
One of the newer medicines is intranasal esketamine, used for people who have not responded to other medicines and treatments (treatment-resistant depression); it may work faster than oral antidepressants.
Esketamine is approved by the US FDA for treatment-resistant depression. It is given only in clinics under medical supervision, because it can cause side effects such as dizziness, feeling detached from oneself, and a rise in blood pressure.
Other new medicines have also been approved in recent years; for example, zuranolone was approved by the FDA in 2023 for postpartum depression.
One approach for treatment-resistant depression is to add another medicine to the antidepressant (for example, certain antipsychotics or lithium). This should only be done by a specialist doctor.
Many people choose and take antidepressants themselves, and because they stop them the wrong way or do not understand the side effects, the depression comes back and they think the medicine did not suit them.
It is usually recommended to continue medication for at least six months after recovery. Stopping should be gradual and supervised by a doctor; stopping suddenly can cause withdrawal symptoms or a return of depression.
Important note about antidepressants
In some children, teenagers and young adults under 25, antidepressants can increase suicidal thoughts and behaviour, especially in the first few weeks of treatment or when the dose changes. The US FDA advises family and those close to the person to watch them carefully during the first weeks of treatment.
Antidepressants in pregnancy
If you are pregnant, breastfeeding or planning a pregnancy, and you take or want to start an antidepressant, always talk to your doctor, because some medicines for depression can affect the baby.
Psychological therapy for depression
Several types of therapy are suitable for depression, and psychologists and counsellors use one of them depending on the theory and approach they work with.
Research shows that CBT and interpersonal therapy (IPT) are effective for depression. My personal experience is that sometimes a person with depression does not want to talk, or does not have the energy to, at the very time they need help most. If this is you, I have two suggestions:
1. Call a free phone support line; in Australia, Lifeline (13 11 14) and Beyond Blue (1300 22 4636). 2. Talk to a psychologist or counsellor who works online or by phone, so you do not need to leave home for a session.
If you want to know how CBT is used to treat depression, read the article on CBT and depression.
If you have severe depression and are thinking about suicide, please talk to someone right now. In Australia you can call Lifeline (13 11 14) or the Suicide Call Back Service (1300 659 467) at any time of the day or night; if you are in immediate danger, call 000 or go to your nearest hospital emergency department.
The truth is that when we are depressed, it is as if we are locked in a box of our own, so caught up in daily life that we forget how big the world is, that we may simply be in the wrong place, or that we may not have all the information.
Depression narrows how we see things and makes us think there is no other way; but depression is treatable, and reaching out for help, even when it is hard, can change the path ahead.
Brain stimulation treatments for depression
When psychotherapy and medication have not reduced symptoms, brain stimulation is another option. There are several types; some are FDA-approved, while others are still experimental.
Although it is not the first choice for treating depression, it is a sensible option when other treatments have not worked, and it can be used alongside medication and psychotherapy.
Brain stimulation treatments use an electrical current or a controlled magnetic field to change activity in parts of the brain. For example, in ECT a brief electrical current causes a short, controlled seizure under general anaesthetic; in TMS, a magnetic field stimulates nerve cells without anaesthetic.
The most common brain stimulation treatments for depression are shown in the table below:
Brain stimulation treatments
| Treatment | How it works | Status |
|---|---|---|
| ECT (electroconvulsive therapy) | Under general anaesthetic, a brief electrical current causes a controlled seizure; usually 2 to 3 times a week | Approved; the oldest and one of the most effective treatments for severe depression |
| rTMS (repetitive transcranial magnetic stimulation) | No anaesthetic; a magnetic coil is placed on the head; usually daily sessions over several weeks | FDA-approved for treatment-resistant depression |
| VNS (vagus nerve stimulation) | A device implanted under the skin of the chest stimulates the vagus nerve with mild electrical pulses | FDA-approved for chronic treatment-resistant depression; it usually works slowly |
| MST (magnetic seizure therapy) | Like ECT under anaesthetic, but using a magnetic field | Experimental |
| DBS (deep brain stimulation) | Electrodes implanted in the brain through surgery | Experimental for depression |
ECT and TMS are the most widely used; ECT is the oldest, and the others are often described as experimental. Brain stimulation is used only for specific mental health conditions.
ECT, TMS and VNS are FDA-approved for depression. Taking antidepressants long-term when they are not reducing symptoms is not ideal, and in those cases brain stimulation treatments can be considered.
These treatments, especially ECT, become more urgent when a person is at serious risk of suicide, or so unwell that they are not eating or drinking.
ECT compared with TMS
| Feature | ECT | TMS |
|---|---|---|
| Anaesthetic | Needed (brief general anaesthetic) | Not needed |
| How it works | Brief electrical current and a controlled seizure | Magnetic field, no seizure |
| Usual number of sessions | About 6 to 12 sessions, 2 to 3 times a week | Daily sessions, 5 days a week, for about 4 to 6 weeks |
| Common side effects | Headache, short-term confusion, usually temporary memory problems | Headache, scalp discomfort where the coil is placed |
| Main use | Severe depression, high suicide risk, depression with psychosis | Treatment-resistant depression |
| After a session | Needs rest and someone to accompany you | Return to daily activities straight away |
VNS needs surgery: a device like a pacemaker is implanted under the skin of the chest and connected by a wire to the vagus nerve in the neck, which it stimulates with mild electrical pulses.
Herbal and alternative treatments
Are there herbal or home treatments for depression? Mothers often ask this, looking for herbal treatment for postnatal depression that will not harm their baby. The FDA has not approved any purely herbal medicine for depression. Vitamin D and the herb St John's wort are sometimes used for depression, but they are not risk-free: St John's wort interacts with many medicines, including antidepressants and the contraceptive pill, and should not be taken in pregnancy or while breastfeeding without medical advice.
I recommend not taking even vitamin D without talking to your doctor, because there is not enough evidence that it treats depression, and you may not be low in it.
Treating seasonal depression
Seasonal depression is a type of depression that comes with the change of seasons, usually in autumn and winter, and improves in spring and summer. It is more common in places with shorter winter days.
One of the main treatments is light therapy: sitting each day in front of a special light box that gives off bright light similar to daylight. Psychotherapy (especially CBT) and medication may also be used. People with certain eye or skin conditions, or who take medicines that increase sensitivity to light, should talk to a doctor before light therapy.
Light therapy is best done with a doctor's guidance.
Self-help for depression
Sometimes we cannot reach a counsellor when we need guidance, or the professional we want cannot see us for a few days. There are some things you can do at home that help with depression:
A note from my own experience: with a skilled professional who suits your needs, you may start to feel better after just the first few sentences of a conversation.
- If your depression is not severe and you can manage it, go outside and walk for 30 minutes a day.
- Keep regular times for sleeping and waking.
- Break the things you need to do into small tasks.
- Try to talk with people you trust.
- Put off big life decisions, such as marriage, divorce or changing jobs.
- Talk through your decisions with people you trust.
- Avoid drugs, nicotine and medicines not prescribed by a doctor.
Guidance for partners of people with depression
If your partner has depression, it has probably affected you too. During my own depression I felt the gap left by the people around me not understanding depression, and I have read about it ever since, so here are some things that can help recovery:
1. Remember that life is not easy, and we can never fully understand another person or put ourselves completely in their place. Like all of us, your partner has met a problem in the whirlwind of daily life that they have not yet been able to get past, and you can help them come through it and return to their life.
2. Please do not tell your partner "It's nothing, you're making a big deal of it" or anything similar.
3. Make sure your support does not turn into controlling or pressuring them; give them space and stay close.
4. During depression a person is more sensitive, and small comments can weigh on them more than usual; be as kind and patient as you can. If your partner talks about death or suicide, take it seriously and call Lifeline (13 11 14), or 000 if they are in immediate danger.
5. Show your appreciation and tell your partner how much they mean to you.
6. Your needs matter too, but at this time your partner needs support more than ever. So that you do not burn out, get help from friends, family or a counsellor.
7. Avoid doing things you know your partner has always disliked, or that you have often disagreed about.
8. Have an accurate picture of depression: it is not laziness or a choice, but a treatable illness. Encourage your partner to keep going with treatment.
Summary
This page is updated regularly with current information so that we can learn, live and help one another; please share your comments and feedback. I am truly glad you are here.