Induction — Psychiatry

Use: The two classification systems that form the basis of psychiatric diagnosis

• ICD-10 and DSM-5 = the two psychiatric classification systems
• Used to define and diagnose the major psychiatric illnesses

• Major depression (DSM-5) = severe depression (ICD-10)

Use: How psychiatric symptoms arise alongside medical disease (liaison psychiatry framework)

• Direct result of physical disease
• Psychological reaction to disease
• Psychiatric disorder leads to physical symptoms
• Psychiatric disorder presents as a physical disorder

Use: The broad categories of illness that fall within psychiatry

• 'Functional' or 'non-organic'
• 'Organic'
• Learning disability
• Personality disorders

Use: How mental illness is conceptually bounded when making a psychiatric diagnosis

• Mental illness (mind) sits at the centre
• Bounded by Physical illness (body)
• Bounded by Deviance (action)
• Bounded by Mental health

Use: Framework grouping common mental disorders into anxiety- vs mood-disorder branches

• PTSD
• Panic Disorder
• OCD
• Generalised Anxiety Disorder
• Phobias

• Dysthymic Disorder
• Major Depression

• Bipolar I
• Bipolar II
• Cyclothymic Disorder

Use: Screen for depression, esp. in patients with established physical disease; ≥2 questions on mood and interest over the last month

• 'During the last month, have you often been bothered by feeling down, depressed or hopeless?'
• 'During the last month, have you often been bothered by having little interest or pleasure in doing things?'

Use: Diagnose an adjustment reaction to a psychosocial stressor.

• Onset of symptoms within 1 month of exposure to an identifiable psychosocial stressor, not of an unusual or catastrophic type
• Symptoms/behavioural disturbance = depressed or anxiety reaction, or conduct disorder (in children)
• Do not usually persist >6 months after cessation of the stress or its consequences — unless prolonged depressive reaction

Use: Features pointing to true mental illness over an adjustment reaction.

• Change of mood that is persistent, extreme, disabling
• Bizarre symptoms (psychosis, aggression)
• Maladjustment to illness
• Suicidality
• Physical function poorer than expected
• Recovery slower than expected
• Poor social interaction

Use: Grief/adjustment trajectory after loss or diagnosis, plotted against morale/competence over time.

• Shock/numbness → denial → fear → anger → depression → understanding → acceptance → moving on

Use: Antipsychotic-related metabolic complication.

• Central obesity
• High blood pressure
• High triglycerides
• Low HDL-cholesterol
• Insulin resistance

Use: Recognise depression against symptom overlap with physical illness.

• Low mood, fatigue, anhedonia
• Loss of confidence/self-esteem
• Disturbed sleep, appetite, energy levels, concentration, libido
• Psychomotor agitation/retardation
• Recurrent thoughts of death or suicide
• Impact on social, scholastic or occupational function
• Irritability, frustration, anger, anxiety, fear
• Pain, discomfort
• Lack of self-care

Use: Service framework — what a liaison psychiatry service covers.

• Psychological reaction to physical illness
• Delirium; dementia; disturbed behaviour
• Section 136 (S136) patients
• Self-harm; substance use
• Medically unexplained symptoms; capacity
• Severe mental illness/psychosis
• Perinatal psychiatry
• Medical/surgical patients with comorbid mental health problems

Use: Classify antipsychotics by generation / side-effect profile

• Typical (neuroleptic) vs atypical

• FGA — D2 antagonists (haloperidol, trifluoperazine); EPSE via nigrostriatal D2 blockade
• SGA — 5HT2A + D2 antagonists (clozapine, olanzapine, quetiapine, risperidone); lower EPSE, more metabolic
• TGA — dopamine partial agonists (aripiprazole first licensed; brexpiprazole, cariprazine, lumateperone)

Use: Recognise neuroleptic malignant syndrome

• Increasing fever without apparent cause
• Muscle rigidity
• Tachycardia
• CPK more than 1000 units

Use: Frame bipolar treatment

• Acute manic episode
• Depressive episode
• Prophylactic treatment
• Only 1/3 respond to monotherapy

Use: Sequence antidepressant prescribing

• Full efficacy not until 6 weeks
• Monitor closely early for increased suicidality
• Assess formally after >=4 weeks
• Effective → continue >=6 months after recovery (stop too soon → 50% relapse)
• Minor response → titrate up; switching better than augmenting
• No response by 4 weeks / poor tolerability → switch class; don't keep increasing dose

Use: Rank antidepressant classes

• First-line — SSRI (favourable risk-benefit)
• Third-line — SNRI (venlafaxine) / NaSSA (mirtazapine)
• Fourth-line — TCA (nortriptyline, clomipramine) / MAOI (moclobemide)
• Choice driven by side-effect profile, preference, prior experience, safety in overdose, interactions

Use: Distinguish anxiolytic classes

• Benzodiazepines — GABAergic; dependence/tolerance; short-term acute distress only
• Beta-blockers (propranolol) — somatic anxiety only, not cognitive
• Buspirone — 5-HT1A agonist, non-GABAergic, non-sedating; up to 4 weeks; not for panic/short-term