Psychiatry

Persistent low mood and/or anhedonia ≥2 weeks with cognitive, somatic and functional change. NICE 2022 grades it less severe (PHQ-9 <16) vs more severe (≥16) rather than mild/moderate/severe.

Recurrent episodes of mania/hypomania and depression. Mania = ≥1 week elevated/irritable mood + ≥3 symptoms (grandiosity, ↓sleep need, pressured speech, flight of ideas, distractibility, risk-taking) with marked impairment ± psychosis. Hypomania = ≥4 days, no marked impairment/psychosis.

Depressive episode with onset typically within the first weeks–months postpartum. Distinct from transient "baby blues" (days 3–10, self-limiting) and from postpartum psychosis (a psychiatric emergency).

Excessive, hard-to-control worry about multiple domains on most days for ≥6 months, with somatic arousal (restlessness, fatigue, poor concentration, irritability, muscle tension, sleep disturbance).

Recurrent unexpected panic attacks (abrupt surge of fear peaking within minutes with somatic symptoms) plus ≥1 month of persistent worry about further attacks or maladaptive change in behaviour.

Obsessions (intrusive, unwanted, anxiety-provoking thoughts/images/urges) and/or compulsions (repetitive behaviours or mental acts performed to neutralise them), recognised as excessive, time-consuming or impairing.

Develops after exposure to actual/threatened death, serious injury or sexual violence, with four symptom clusters: re-experiencing, avoidance, negative cognitions/mood, and hyperarousal, persisting >1 month.

A transient, severe reaction to an exceptional physical or psychological stressor, developing within minutes–hours and usually resolving within days (ICD) — by definition within the first month of trauma.

Marked, persistent, out-of-proportion fear of a specific object/situation (specific phobia), social scrutiny (social anxiety disorder) or situations where escape/help is difficult (agoraphobia), with avoidance. See the Health Psychology page for the full discrimination.

A psychotic disorder with ≥6 months of disturbance including ≥1 month of active symptoms: delusions, hallucinations (often 3rd-person auditory), disorganised speech, and negative symptoms (blunted affect, avolition, alogia).

An umbrella for presentations with loss of contact with reality — delusions, hallucinations, disorganisation — including brief psychotic disorder and first-episode psychosis before a specific diagnosis is established.

≥1 month of one or more fixed delusions WITHOUT prominent hallucinations, disorganisation or negative symptoms; functioning is otherwise relatively preserved.

Concurrent prominent mood (manic or depressive) and schizophrenic symptoms, with psychotic symptoms present for ≥2 weeks in the ABSENCE of prominent mood symptoms at some point.

A psychiatric EMERGENCY of rapid-onset psychosis (mania, delusions, hallucinations, confusion) typically within the first 2 weeks postpartum. ~1–2/1000 births; higher with bipolar/previous PP psychosis.

A neurodevelopmental disorder of persistent inattention and/or hyperactivity-impulsivity, present before age 12, in ≥2 settings, causing functional impairment. Persists into adulthood in many.

A neurodevelopmental disorder of persistent deficits in social communication and interaction PLUS restricted, repetitive patterns of behaviour, interests or activities, present from early development.

Physiological withdrawal on stopping/reducing in dependence. Alcohol withdrawal: 6–12h tremor/anxiety/sweating, 12–24h seizures, 24–48h+ delirium tremens. Opioid withdrawal: distressing but rarely life-threatening.

A problematic pattern of substance use causing clinically significant impairment — features of dependence: tolerance, withdrawal, compulsion, loss of control, salience, persistence despite harm.

Persistent, recurrent problematic gambling causing significant impairment — a behavioural addiction sharing features with substance dependence (preoccupation, tolerance, chasing losses, loss of control, harm).

Anorexia nervosa (restriction → significantly low weight, fear of weight gain, body-image disturbance), bulimia nervosa (binge–purge cycles at normal/above weight), and binge-eating disorder.

Enduring, pervasive, inflexible patterns of inner experience and behaviour deviating markedly from cultural expectation, beginning by adolescence/early adulthood and causing distress/impairment. Clusters A (odd), B (dramatic), C (anxious).

Intentional self-poisoning or self-injury, irrespective of motive or suicidal intent. A behaviour, not a diagnosis — and the strongest single predictor of future suicide.

One or more distressing somatic symptoms PLUS excessive thoughts, feelings or behaviours about them (health anxiety, disproportionate time/energy), persisting >6 months — regardless of whether a medical explanation exists.

Marked and persistent incongruence between a person’s experienced gender and their assigned sex, associated with clinically significant distress or impairment (dysphoria). Gender incongruence itself is not a mental illness (ICD-11).

An emotional/behavioural reaction to an identifiable psychosocial stressor (divorce, diagnosis, job loss), out of proportion or impairing function, beginning within ~1 month and resolving within ~6 months of the stressor ending. Milder than depression/PTSD.

A transient, very common (~50–80%) low mood, tearfulness and emotional lability in the first week or two postpartum, peaking ~day 3–5. Self-limiting and needs only support — the key is distinguishing it from postnatal depression and the emergency of postpartum psychosis.

An OCD-spectrum disorder of preoccupation with a perceived defect in appearance that is unnoticeable or slight to others, driving repetitive behaviours (mirror-checking, camouflaging, reassurance-seeking) and significant distress/impairment.

Neurological symptoms (weakness, sensory loss, non-epileptic seizures, blindness) that are genuine and unconsciously produced — incompatible with recognised neurological disease on examination. Not feigned (unlike malingering/factitious).

Intentional falsification or induction of physical/psychological symptoms in oneself (Munchausen syndrome) or another (fabricated/induced illness, "by proxy") to assume the SICK ROLE — with NO external incentive (which separates it from malingering).

Preoccupation with HAVING or ACQUIRING a serious illness, with high health anxiety, despite minimal or no somatic symptoms and repeated negative investigations (formerly hypochondriasis). Contrast with somatic symptom disorder, where distressing somatic symptoms ARE present.

Intentional feigning or exaggeration of physical/psychological symptoms motivated by an EXTERNAL incentive — money, benefits, avoiding work/military service/criminal responsibility, or obtaining drugs. It is NOT a psychiatric disorder, but a key discriminator.

A rare, life-threatening reaction to dopamine antagonism: rigidity, hyperthermia, autonomic instability and altered consciousness, with a markedly raised creatine kinase. It follows antipsychotics — typical more than atypical — but equally follows abrupt withdrawal of levodopa or a dopamine agonist in Parkinson disease.

Persistent physical symptoms that are genuinely distressing and disabling but are not explained by identifiable organic disease after appropriate assessment. They are common — a substantial proportion of new outpatient presentations — and the symptoms are real; "unexplained" describes the state of the investigation, not the authenticity of the complaint.