What are the symptoms of a mental illness? If a friend or loved one doesn't seem themselves, how do you spot the difference between a bad mood and something more serious? Drinking too much, being a party pooper, crying all the time or any other ongoing, significant change in a person’s behaviours, thoughts or feelings could be tell-tale signs of a mental illness.

Learn the signs that could prompt you to think that a friend or family member is among the 1 in 5 Australians dealing with a mental health issue.

Often it's not a single change but a combination. The following 9 signs are not to help you diagnose a mental health issue, but instead to reassure you that there might be good reason to seek more information about your concerns.

1. Feeling anxious or worried

We all get worried or stressed from time to time. But anxiety could be the sign of a mental health issue if it’s constant and interferes all the time. Other symptoms of anxiety may include heart palpitations, shortness of breath, headache, restlessness, diarrhoea or a racing mind.

2. Feeling depressed or unhappy

Have you noticed that your friend has lost interest in a hobby you used to share? If they've also seemed sad or irritable for the last few weeks or more, lacking in motivation and energy or are teary all the time, they might be dealing with depression.

3. Emotional outbursts

Everyone has different moods, but sudden and dramatic changes in mood, such as extreme distress or anger, can be a symptom of mental illness.

4. Sleep problems

Generally, we need 7-9 hours of sleep each night. Persisting changes to a person’s sleep patterns could be a symptom of a mental illness. For example insomnia could be a sign of anxiety or substance abuse. Sleeping too much or too little could indicate depression or an sleeping disorder.

5. Weight or appetite changes

Many of us want to lose a few kilos, but for some people fluctuating weight or rapid weight loss could be one of the warning signs of a mental illness, such as depression or an eating disorder. Other mental health issues can impact appetite and weight too.

6. Quiet or withdrawn

We all need quiet time occasionally, but withdrawing from life, especially if this is a major change, could indicate a mental health issue. If a friend or loved one is regularly isolating themselves, they may have depression, bipolar, a psychotic disorder, or another mental health issue. Refusing to join in social activities may be a sign they need help.

7. Substance abuse

Are you worried a loved one is drinking too much? Using substances, such as alcohol or drugs, to cope can be a sign of, and a contributor to, mental health issues.

8. Feeling guilty or worthless

Thoughts like ‘I’m a failure’, ‘It’s my fault’ or ‘I’m worthless’ are all possible signs of a mental health issue, such as depression. Your friend or loved one may need help if they’re frequently criticising or blaming themselves. When severe, a person may express a feeling to hurt or kill themselves. This feeling could mean the person is suicidal and urgent help is needed. Call Triple zero (000) for an ambulance immediately.

9. Changes in behaviour or feelings

A mental illness may start out as subtle changes to a person’s feelings, thinking and behaviour. Ongoing and significant changes could be a sign that they have or are developing a mental health issue. If something doesn’t seem ‘quite right’, it’s important to start the conversation about getting help.

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Last reviewed: December 2018