While the exact cause of psychosis is unknown, research suggests it results from a combination of genetic, biological, environmental, and psychological factors:

Biological factors:

• Genetic traits inherited or chemical imbalances in the brain can increase vulnerability to psychosis.
• Some individuals may be prone to psychosis, and life stresses can trigger a psychotic episode. Stresses include short-term stress such as work deadlines and arguments, and long-term stress such as those arising from relationship and financial difficulties.
• Psychosis can sometimes arise such as HIV, Alzheimer’s disease, Parkinson's disease, or brain tumours.

Substance abuse:

• Misuse of alcohol or drug can cause psychotic episodes.
• Withdrawal from long-term alcohol or drug use may also trigger psychosis. Withdrawal symptoms can include headaches, fatigue, difficulty sleeping, and irritability, which may further complicate the recovery process.

Proper medical supervision and support, such as services offered by the National Addictions Management Service (NAMS) are crucial for individuals undergoing treatment for substance use disorders to minimise the risk of psychosis and other severe withdrawal symptoms.

Psychological factors:

• Mental health conditions like schizophrenia, depression, and bipolar disorder.
• Sleep deprivation.
• Severe prolonged stress or trauma.

Social factors:

• Traumatic events, such as childhood abuse, and an individual’s upbringing and surroundings.

Psychosis can show up in different ways, but common signs include changes in perception, thinking, emotions, and behaviour.

These changes can be distressing and may make it harder to cope with daily activities or connect with others.

Early signs of psychosis:

• Feeling suspicious or paranoid, like believing others are watching or talking about them.
• Occasionally hearing voices that aren’t really there.
• Difficulty thinking logically.

Abnormal experiences or behaviours:

• Hallucinations – Hallucinations occur when individuals hear, see, feel, smell, or taste things that aren't there. For example, they might hear voices telling them what to do, even though no one is actually speaking.
• Delusions – Delusions are strong beliefs that don’t match reality and don’t change, even when there’s evidence that they aren’t true. For example, individuals with psychosis may believe others are plotting against them or trying to harm them.
• Disorganised thinking or speech – Individuals with psychosis have trouble thinking in an organised way. They may have difficulty getting to the main point of a conversation and may talk about various subjects before reaching the intended topic. Sometimes, they make up words or say things that do not make sense.

Changes in behaviours due to psychosis:

• Showing little to no emotion or not changing your facial expression.
• Not moving or talking much.
• Neglecting personal hygiene like not taking showers or keeping clean.
• Losing interest in spending time with others or having fun.

Cognitive symptoms:

Individuals with psychosis have difficulty:

• Learning and remembering.
• Understanding speech or other forms of communication.
• Making sense of new information.
• Solving problems.
• Starting or maintaining goal-directed tasks.

Emotional symptoms:

• Individuals with psychosis often experience anxiety or depression.