Depression

Dr Lisa Beckett

May 2022

What is depression?

Depression is a common mental health condition involving a persistent low mood. It’s more than just a bad day or feeling sad. Depression involves intense, sad or depressed feelings last more than two weeks and affect how we live our lives.

If you have concerns you might be depressed it’s important to speak to someone you trust or your doctor. Help is available and effective.

What are the symptoms of depression?

Symptoms of depression vary significantly from one person to the next. They may be physical or psychological.

Physical symptoms include:

  • loss or gain of appetite or weight
  • poor sleep or excessive sleep
  • difficulty concentrating
  • low libido
  • fatigue
  • self-harm

Psychological symptoms can include:

  • feeling sad, tearful, anxious or irritable
  • feeling alone
  • hopelessness
  • guilt
  • anger
  • feeling suicidal

You may find you lack motivation, withdraw from social activities or use drugs or alcohol to cope.

Types of depression

There are a number of types of depression. Most commonly:

  • major depressive disorder
  • psychotic depression
  • persistent depressive disorder
  • perinatal depression
  • seasonal affective disorder
  • pre-menstrual dysphoric disorder

What treatments are available?

Treatment for depression can be grouped into 3 main types:

  • psychological
  • medications
  • self-help and lifestyle

Treatments are often used together and may vary depending on how severe the depression is.

Self-help and lifestyle treatments for depression

There are many techniques and therapies that can be of benefit in depression. Examples include:

  • exercise
  • good nutrition
  • meditation
  • yoga
  • massage therapy
  • St John’s wort
  • alcohol and drug avoidance

Exercise
Exercise can increase chemicals in the brain such as serotonin and endorphins. These chemicals can improve mood, sleep, libido and appetite.  Regular exercise can help in depression by:

  • increasing energy
  • improving sleep
  • acting as a distraction from negative thoughts
  • improving general health
  • providing social support if done with others
  • giving a sense of achievement and control

St John's wort
St John’s wort is a herbal medication used to help depression. Studies have shown it can be effective for mild depression but ineffective for more significant depression.

Side effects include dry mouth, dizziness, fatigue and gastrointestinal upset. St John’s wort is known to interact with a number of commonly prescribed medications (including the contraceptive pill) so it is important to let your doctor know if you are taking it.

Psychological therapies

Psychological therapies are an effective way to treat depression. They may be effective on their own or used in combination with other treatments. Psychological treatments may be one on one, group based or online.

The aim of psychological therapy is to help us change the way we think and respond. Psychology may give us a better understanding of why we feel the way we do, help us recognise any unresolved issues, change unhelpful thoughts and develop skills to improve our mental health. They are important for helping prevent relapses when we recover from depression.

There are a number of different forms of psychological therapies including:

Cognitive behavioural therapy (CBT)
CBT involves recognising our thoughts about anxiety and re-framing them to decrease our stress response. The way we think affects how we feel. It is possible to challenge our thoughts and recognise cognitive distortions - unhelpful thought patterns.

CBT can be completed individually in person or online, or in small groups. It works best when guided by a qualified clinician. Sessions are usually completed over several weeks to months.

CBT is one of the most effective treatments for depression.

Mindfulness
Mindfulness has gained in popularity as a tool for mental health. It involves being intentionally aware of what is happening in the present moment, without judgement. Recognising our thoughts, feelings and sensations in the moment, and accepting them without trying to change them.

When we’re depressed we tend to dwell on negative thoughts, often of past experiences or what could go wrong in the future. Mindfulness aims to bring you back to the present moment.

There are a number of mindfulness apps and it is a skill that can be practiced alone or with a clinician.

Interpersonal therapy (IPT)
IPT involves gaining an understanding of how our personality and social circumstances can increase our risk of depression. Interpersonal problems or situations in our work, personal or social relationships may make us vulnerable to developing depression. IPT aims to develop a plan for addressing this and preventing relapse.

Other forms of therapy
There are many forms of psychological therapy that may be helpful for depression including:

  • Positive psychology
  • Acceptance and Commitment (ACT) therapy
  • Narrative therapy
  • Psychotherapy

It is best to be guided by a qualified clinician to determine which suits you best.

e-Mental health programs
A number of online mental health programs exist that allow you to access support on your phone or computer. They can be remarkably effective for mild-moderate depression and anxiety and are often used in combination with medication or one-on-one therapy. Many are free or low cost.

Psychological therapies are an effective way to treat mild-moderate depression for most people. They are often combined with medications or medicinal cannabis treatments and self care.

Even if you decide that medications, medicinal cannabis or self help treatments are more suitable for you, it is recommended that you consider psychological therapy as well.

Medications

When psychological and lifestyle therapies are not helping with depression, medication can be a good option. All medications have risks and benefits and potential side effects and it’s important to discuss these with your doctor before starting.

Antidepressants
There are a number of classes of antidepressants. The main ones used for depression are selective serotonin reuptake inhibitors (SSRIs), serotonin noradrenaline reuptake inhibitors (SNRIs), tricyclics (TCAs) and irreversible monoamine oxidase inhibitors (MAOIs). It can take some trial and error to find the right antidepressant for each person.

SSRIs and SNRIs
SSRIs are first line medications for depressive disorders. Common SSRIs include citalopram, escitalopram, fluoxetine, fluvoxamine, paroxetine and sertraline.

SNRIs are second line for depression. Desvenlafaxine, duloxetine and venlafaxine are common choices.

While very effective for depression there is the potential for temporary worsening of suicidality when starting. This is most common in young people in the first 7-10 days of treatment. They take 2-4 weeks to be effective and should not be stopped suddenly.

Common side effects include sexual difficulties, weight gain, sedation, dry mouth and gastrointestinal upset.

TCA’s and MAIO’s
Tricyclic and irreversible monoamine oxidase inhibitors are used less commonly but can be effective when other medications are not. They are usually used under guidance of a psychiatrist.

Mood stabilisers
Mood stabilisers are commonly used to treat bipolar disorder. They reduce mood swing severity and frequency. Most commonly prescribed by psychiatrists, medications include lithium, sodium valproate and carbamazepine.

Other management for depression
In treatment resistant depression or psychotic depression other management may include:

  • Electroconvulsant therapy (ECT)
  • Repetitive transcranial magnetic stimulation (rTMS)
  • Transcranial direct current stimulation (tDCS)

Medicinal cannabis

When psychological therapies and traditional medications are not effective in treating depression, doctors may consider prescribing cannabis.

Can cannabis be used for depression?

Yes, for some patients cannabis can be used to help treat depression. It may be used alone or in combination with other therapies including psychology or antidepressants.

Cannabis contains more than 100 compounds called cannabinoids. The most well known of these are Δ 9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Our bodies also make their own cannabinoids. Cannabinoids act in the endocannabinoid system and have a wide range of effects. See more here.

CBD is non-psychoactive and acts indirectly on CB2 receptors. Oral CBD is a potentially helpful cannabis treatment for depression and is used first line. It can help with relaxation and regulation of serotonin and dopamine. If ineffective, inhaled CBD or oral THC may be trialled.

THC can be effective for depression. At the right dose it produces euphoria and improves mood as well as helping with sleep. It is important to appreciate that THC is psychoactive and acts on CB1 receptors. This means it can potentially make depression worse at high levels of use. If THC is used it should be started at a low dose and titrated very slowly.

Can cannabis be prescribed for depression in Australia?

Yes it can. Any registered doctor in Australia can prescribe medicinal cannabis with approval from the TGA. You can speak to your GP about how suitable this is for you, or Candor can help you connect to a GP with medicinal cannabis knowledge who can apply for the approvals.

To be eligible you must have been diagnosed with a depressive disorder and have trialled other treatments such as those outlined above. If other treatments have been ineffective or you had unacceptable side effects then medicinal cannabis may be appropriate for you.

What research is there for depression and cannabis?

There have been a number of studies looking at how cannabis can be used to treat depression. Studies have shown up to a 50% reduction in depression. Further testing is required to gain a comprehensive understanding and optimal treatment plans.

References

Childs E, et al. Drug Alcohol Depend 2017;177:136–44

Cutler C, et al. J Affect Disord 2018;235:198⎼205

Stith SS, et al. Frontiers in Pharmacol 2018;9(916):1⎼8

https://www.blackdoginstitute.org.au/resources-support/depression/treatment/