The Complete Guide to All Major Mental Disorders & Their Symptoms
Explore the complete list of major mental disorders, discover their key symptoms, and learn
Mental Disorders & Their Symptoms
Mental health is as important as physical health. According to the World Health Organization (WHO), mental disorders affect hundreds of millions of people globally. World Health Organization+1 Yet despite their prevalence, many people remain uncertain about what kinds of disorders exist—and how to recognise them. This guide lays out the major categories of mental disorders and lists key symptoms so you can increase awareness, reduce stigma, and know when to seek help.
1. Anxiety Disorders
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| Anxiety Disorders |
Definition & common types: Anxiety disorders include conditions such as generalised anxiety disorder (GAD), panic disorder, social anxiety disorder, specific phobias, and others. Better Health Channel+2Cleveland Clinic+2
Key symptoms:
- Persistent, excessive worry or fear about everyday situations
- Physical symptoms like trembling, rapid heartbeat, sweating, dizziness
- Avoidance of feared situations or places
- Panic attacks: sudden intense fear, chest pain, shortness of breath
- These symptoms may interfere with daily life and persist for a long time.
2. Mood Disorders (Depression, Bipolar, etc.)
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| Mood disorders |
Definition: Mood disorders are characterised by significant changes in mood—either persistent low mood (depression) or alternating between low and high mood (bipolar). Healthdirect+1
Key symptoms of depression:
- Persistent sadness, emptiness, or hopelessness
- Loss of interest in activities once enjoyed
- Fatigue, changes in appetite/weight, sleep disturbances
- Thoughts of death or suicide
- Key symptoms of bipolar disorder:
- Episodes of mania: elevated mood, increased energy, reduced need for sleep, impulsive behaviour
- Alternating with depressive episodes
- Wikipedia
3. Psychotic Disorders
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| Psychotic Disorders |
Definition: Psychotic disorders involve a loss of connection with reality. Common example: Schizophrenia. Mayo Clinic+1
Key symptoms:
- Hallucinations (seeing or hearing things that aren’t there)
- Delusions (fixed false beliefs)
- Disorganised thinking and speech
- Social withdrawal, lack of motivation
- When untreated, these disorders can severely disrupt life and functioning.
4. Personality Disorders
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| Personality Disorders |
Definition: A group of disorders characterised by enduring patterns of behaviour and inner experience that deviate markedly from cultural norms and cause distress or impairment. Alter Behavioral Health
Key symptoms vary by type, but may include:
- Instability in relationships, self-image and mood (e.g., borderline personality disorder)
- Detachment from social relationships, limited emotional expression (e.g., schizoid)
- Excessive attention-seeking, grandiosity (e.g., narcissistic)
- Because these patterns are long-term and ingrained, therapy is often needed for change.
5. Eating & Feeding Disorders
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| Eating & Feeding Disorders |
Definition: Disorders characterised by persistent disturbances in eating behaviours and related distressing thoughts and emotions. Common examples: anorexia nervosa, bulimia nervosa, binge-eating disorder. Alter Behavioral Health
Key symptoms:
- Extreme restriction of food intake, fear of gaining weight (anorexia)
- Repeated episodes of binge eating, followed by compensatory behaviours (bulimia)
- Frequent overeating without compensatory behaviour (binge eating)
- These disorders often carry serious physical health risks and require early intervention.
6. Neurodevelopmental Disorders
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| Neurodevelopmental Disorders |
Definition: Conditions that typically manifest early in development, often before the child enters grade school. Include Autism Spectrum Disorder (ASD), Attention‑Deficit/Hyperactivity Disorder (ADHD), learning disorders. Cleveland Clinic+1
Key symptoms:
- ASD: difficulties with social communication and interaction; restricted, repetitive patterns of behaviour
- ADHD: inattention, hyperactivity, impulsivity
- Learning disorders: difficulties in reading, writing, mathematics despite normal intelligence
- Early diagnosis and support can improve outcomes.
7. Trauma- & Stressor-Related Disorders
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| Trauma & Stressor Related Disorders |
Definition: Disorders in which exposure to a traumatic or stressful event is explicitly listed as a diagnostic criterion. Includes Post‑Traumatic Stress Disorder (PTSD), adjustment disorders. Healthdirect+1
Key symptoms of PTSD:
- Intrusive memories, nightmares related to the event
- Avoidance of reminders of the trauma
- Negative changes in thinking and mood (e.g., blaming self, feeling detached)
- Changes in arousal/reactivity (e.g., irritability, hypervigilance)
- Adjustment disorders: Emotional or behavioural symptoms in response to a stressor, within 3 months of onset.
8. Substance-Related & Addictive Disorders
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Definition: Disorders related to the taking of a drug (including alcohol) or to behaviour (such as gambling) and include both dependence and abuse. NCBI
Key symptoms:
- Craving or strong desire to use the substance/behaviour
- Loss of control over use
- Continued use despite harmful consequences
- Withdrawal symptoms when substance is reduced or stopped
- These conditions often co-occur with other mental health disorders and complicate treatment.
Recognition: Common Signs Across Disorders
While each category has its own distinct features, there are overlapping signs that may signal a mental disorder:
Why It Matters & What To Do
Understanding the full spectrum of mental disorders matters because:
- It helps reduce stigma and encourages people to seek help early
- Early detection and treatment improve outcomes
- Awareness empowers friends/family to support loved ones
If you recognise symptoms in yourself or someone else:
- Reach out to a licensed mental health professional (psychiatrist, psychologist)
- Use available resources (hotlines, support groups)
- Don’t ignore symptoms — early intervention matters
- Encourage an environment of understanding and care, not shame
Mental disorders cover a wide range of conditions—from anxiety and mood disorders to neurodevelopmental and substance-related disorders. Recognising their symptoms is the first step to taking action. With awareness, support, and professional help, many people living with mental disorders can lead fulfilling lives. If you or someone you care about is showing signs, don’t wait — reach out.