Psychiatry: common disorders and their management

In short

Psychiatry deals with disorders of thought, mood, perception, cognition, behaviour and substance use, diagnosed mainly by history and the mental status examination (MSE) rather than by investigations. India's National Mental Health Survey 2015-16 found a current prevalence of about 10.6% in adults with a treatment gap of 70-90%, so every clinician — not only the specialist — must screen, treat the common conditions and refer the rest. It is examined in the final-year MBBS psychiatry paper and OSCE (MSE, suicide risk, one long case), in NEET-PG/INI-CET, and tested in interviews for internship, junior residency, DMHP/Tele-MANAS posts, de-addiction centres and CRO/pharmacovigilance jobs. Practice in India is governed by the Mental Healthcare Act, 2017, the NDPS Act, 1985, and the Rights of Persons with Disabilities Act, 2016.

Explained

Classification, assessment and the MSE

• Two systems: ICD-11 (WHO, in force for reporting since January 2022; most Indian hospital records still use ICD-10) and DSM-5-TR (APA, used in research). ICD-11 dropped schizophrenia subtypes (paranoid, hebephrenic) and uses symptom-domain qualifiers instead.
• Diagnosis needs three things: symptoms of sufficient number and duration, significant distress or socio-occupational dysfunction, and exclusion of an organic cause or substance effect.
• MSE components: general appearance and behaviour; psychomotor activity; speech (rate, volume, tone, relevance); mood (subjective) and affect (objective, its range and congruence); thought — stream, form (loosening, tangentiality, thought block), content (delusions, obsessions, suicidal ideas) and possession (thought alienation); perception (hallucinations, illusions, depersonalisation); cognition (consciousness, orientation, attention, memory, intelligence, abstraction); insight (graded I-VI) and judgement.
• Delusion = a fixed false unshakeable belief out of keeping with the patient's culture; hallucination = perception without a stimulus; illusion = misperception of a real stimulus; obsession = ego-dystonic recurrent intrusive thought resisted by the patient.
• Rating scales: PHQ-9 and HAM-D (depression), GAD-7 (anxiety), YMRS (mania), BPRS/PANSS (psychosis), Y-BOCS (OCD), MMSE/MoCA and HMSE (cognition), AUDIT and CAGE (alcohol), IDEAS (disability certification for mental illness in India).
• Investigations are to exclude, not confirm: haemogram, glucose, electrolytes, calcium, renal and liver function, TSH, B12, HIV/VDRL where indicated, urine drug screen, CT/MRI brain and EEG for first-episode psychosis with atypical features, late onset, focal signs or delirium.

Psychotic disorders

• Schizophrenia: ICD-11/DSM-5 require characteristic symptoms for ≥1 month (ICD) or ≥6 months with ≥1 month active phase (DSM). Lifetime risk about 1%; onset late teens to early 30s, earlier in men.
• Positive symptoms: delusions (persecutory, reference, control, grandiose), hallucinations (typically third-person auditory), disorganised speech and behaviour. Negative: avolition, alogia, affective blunting, anhedonia, asociality — these drive long-term disability. Also cognitive and catatonic domains.
• Schneider's first-rank symptoms (audible thoughts, voices arguing, running commentary, thought insertion/withdrawal/broadcasting, made feelings/impulses/acts, somatic passivity, delusional perception) are suggestive, not pathognomonic.
• Differentials: acute and transient psychotic disorder (abrupt onset, <1 month, common in India, often post-stress, good prognosis), schizoaffective disorder, delusional disorder (≥3 months, non-bizarre delusion, preserved functioning), substance-induced psychosis (cannabis, amphetamine), mania with psychotic symptoms, delirium, temporal lobe epilepsy.
• Management: a single antipsychotic at the lowest effective dose — risperidone 2-6 mg/day, olanzapine 10-20 mg, aripiprazole 10-30 mg, haloperidol 5-15 mg; long-acting injectables for non-adherence. Assess response at 4-6 weeks. Treatment resistance = failure of two adequate antipsychotic trials → clozapine (300-450 mg/day) with mandatory absolute neutrophil count monitoring (weekly for 18 weeks, then fortnightly to one year, then monthly) for agranulocytosis (~0.8%); also causes sialorrhoea, sedation, seizures, myocarditis, weight gain.
• Side-effect groups: extrapyramidal — acute dystonia (hours-days; treat with IM promethazine or anticholinergic), parkinsonism, akathisia (propranolol/benzodiazepine), tardive dyskinesia (late, may be irreversible); metabolic — weight gain, dyslipidaemia, diabetes (olanzapine and clozapine worst); hyperprolactinaemia (risperidone, amisulpride, haloperidol); QTc prolongation; neuroleptic malignant syndrome.
• Psychosocial: psychoeducation of the family, adherence work, social skills and vocational training, community follow-up through the District Mental Health Programme.

Mood disorders

• Depressive episode (ICD): ≥2 weeks of depressed mood, anhedonia and fatigue plus somatic/cognitive symptoms — sleep and appetite change, guilt, worthlessness, poor concentration, death wishes. Graded mild/moderate/severe, with or without psychotic symptoms. Somatic presentation (aches, "gas", weakness) is very common in Indian primary care.
• Management: SSRIs first line — fluoxetine 20-60 mg, sertraline 50-200 mg, escitalopram 10-20 mg; others — venlafaxine, duloxetine, mirtazapine (sedating, appetite-increasing), bupropion (no sexual dysfunction), TCAs such as amitriptyline/imipramine (cardiotoxic in overdose). Onset 2-4 weeks, assess at 4-6 weeks, continue 6-9 months after remission, longer with recurrences. Add CBT, IPT or behavioural activation; exercise and sleep hygiene.
• Key cautions: SSRI-induced hyponatraemia (SIADH) in the elderly, GI bleeding with NSAIDs, discontinuation syndrome with paroxetine/venlafaxine, serotonin syndrome when combined with tramadol, linezolid or MAOIs, and a switch to mania in bipolar patients if used unopposed.
• Mania: ≥1 week of elevated/irritable mood with inflated self-esteem, decreased need for sleep, pressured speech, flight of ideas, distractibility, risk-taking. Bipolar I = mania (± depression); bipolar II = hypomania + depression; cyclothymia = subthreshold swings for ≥2 years.
• Treatment of mania: antipsychotic (olanzapine, risperidone, haloperidol) ± lithium or valproate, short-term benzodiazepine for sleep, stop antidepressants. Maintenance: lithium (600-1,200 mg/day; levels, TSH, creatinine, calcium monitoring), valproate, quetiapine, lamotrigine (best for bipolar depression; slow titration for rash/SJS risk).
• Valproate must be avoided in women of childbearing potential unless no alternative exists and contraception is assured — neural tube defects and a 30-40% risk of neurodevelopmental impairment. Lithium carries a small risk of Ebstein's anomaly; carbamazepine is also teratogenic.
• ECT is indicated for severe depression with suicidal risk or food refusal, catatonia, treatment-resistant mania or psychosis, and puerperal psychosis — the fastest-acting option; main adverse effect is transient retrograde/anterograde amnesia. Under the Mental Healthcare Act, 2017, unmodified ECT (without anaesthesia and muscle relaxant) is prohibited, and ECT in minors requires guardian consent plus Mental Health Review Board permission.

Anxiety, obsessive-compulsive, stress-related and somatic disorders

• Panic disorder: recurrent unexpected panic attacks (peak in ~10 minutes: palpitations, dyspnoea, chest pain, fear of dying) with anticipatory anxiety; rule out thyrotoxicosis, arrhythmia, asthma, phaeochromocytoma, caffeine. Treat with an SSRI + CBT; benzodiazepine only as short-term cover.
• Generalised anxiety disorder: ≥6 months of free-floating worry with motor tension and autonomic symptoms. SSRI/SNRI, buspirone, pregabalin; relaxation and CBT.
• Phobias: specific phobia, social anxiety disorder (SSRI + CBT, propranolol for performance anxiety), agoraphobia. Treated by graded exposure and response prevention/systematic desensitisation.
• OCD: obsessions and/or compulsions ≥1 hour/day causing distress; treat with high-dose SSRI (e.g. fluoxetine up to 60-80 mg) for 10-12 weeks, or clomipramine; ERP (exposure and response prevention) is the behavioural treatment of choice; augment with low-dose antipsychotic.
• Acute stress reaction (hours-days), PTSD (re-experiencing, avoidance, hyperarousal, negative cognitions >1 month) — trauma-focused CBT/EMDR first line, SSRI second; prazosin for nightmares. Adjustment disorder follows an identifiable stressor.
• Dissociative (conversion) disorders: pseudoseizures, dissociative amnesia, possession states — frequent in Indian practice; treat with reassurance, suggestion, abreaction, addressing the psychosocial stressor; avoid unnecessary investigations without missing organic disease.
• Somatic symptom disorder, hypochondriasis and chronic pain: regular brief scheduled visits with one doctor, limit investigations, treat comorbid depression, CBT.

Substance use, organic and child disorders

• Dependence syndrome (ICD-10, ≥3 present together at some time during the previous 12 months): craving, impaired control, tolerance, withdrawal, salience over other activities, persistence despite harm.
• Alcohol: withdrawal begins 6-24 h (tremor, sweating, anxiety), seizures 12-48 h, delirium tremens 48-72 h (clouding of consciousness, visual hallucinations, autonomic storm; mortality up to 5-15% untreated). Treat with chlordiazepoxide or lorazepam (lorazepam in liver disease), parenteral thiamine 100-500 mg before any glucose to prevent Wernicke's encephalopathy (confusion, ataxia, ophthalmoplegia), fluids, electrolytes. Anti-craving: naltrexone 50 mg/day (not in opioid use or hepatic failure), acamprosate 666 mg TDS, disulfiram 250 mg (aversive; only with informed consent and supervision), plus motivational interviewing, brief intervention and Alcoholics Anonymous.
• Opioids: withdrawal is distressing but rarely fatal (lacrimation, yawning, piloerection, cramps, diarrhoea). Detoxify with buprenorphine or clonidine; opioid substitution therapy with buprenorphine-naloxone or methadone is the evidence-based maintenance, delivered through NDPS-licensed centres. Naloxone reverses overdose. NDPS Act, 1985 gives an addict who volunteers for treatment immunity from prosecution for consumption (Section 64A).
• Tobacco: nicotine replacement, bupropion, varenicline + behavioural support; COTPA, 2003 and National Tobacco Control Programme. Cannabis: amotivational syndrome, psychosis. Inhalants in street children.
• Delirium: acute onset, fluctuating course, clouded consciousness, inattention, altered sleep-wake cycle, visual hallucinations — always find and treat the cause (infection, hypoxia, electrolytes, drugs, withdrawal); low-dose haloperidol/quetiapine for agitation; benzodiazepines only for withdrawal or hepatic states.
• Dementia: chronic, progressive, clear consciousness, memory and executive decline. Alzheimer's (cholinesterase inhibitors — donepezil, rivastigmine; memantine in moderate-severe), vascular, Lewy body (antipsychotic sensitivity), frontotemporal; exclude reversible causes (B12, hypothyroidism, NPH, subdural, neurosyphilis).
• Child and adolescent: intellectual developmental disorder (IQ-based grading plus adaptive function), autism spectrum disorder (early behavioural intervention), ADHD (methylphenidate, atomoxetine, behaviour therapy), enuresis, tics, specific learning disorder, school refusal.
• Personality disorders: enduring, pervasive patterns from adolescence — paranoid, schizoid, antisocial (dissocial), borderline (emotionally unstable; DBT), histrionic, anankastic, anxious-avoidant, dependent.

Emergencies, suicide and the Indian legal-programmatic frame

• Suicide risk assessment: ask directly about ideas, intent, plan, means, preparatory acts and protective factors. Risk raised by past attempt (strongest predictor), psychiatric illness, substance use, hopelessness, chronic pain, male sex, elderly, social isolation, recent loss. India records about 1.7 lakh suicides a year (NCRB), the leading means being hanging, poisoning (pesticides) and self-immolation; pesticide access restriction is a proven population measure. Tele-MANAS helpline 14416 (launched October 2022) and the National Suicide Prevention Strategy, 2022.
• Neuroleptic malignant syndrome: fever, lead-pipe rigidity, altered mental state, autonomic instability, raised CK and leucocytosis. Stop the antipsychotic, cool, hydrate, dantrolene/bromocriptine, ECT if needed. Serotonin syndrome differs — rapid onset, clonus, hyperreflexia, diarrhoea; treat with cyproheptadine.
• Lithium toxicity: coarse tremor, vomiting, diarrhoea, ataxia, dysarthria, confusion, seizures — precipitated by dehydration, NSAIDs, thiazides, ACE inhibitors, low salt; haemodialysis above about 4.0 mEq/L or with severe features.
• Catatonia: mutism, negativism, posturing, waxy flexibility, stupor → lorazepam challenge, then ECT; watch for the malignant form.
• Mental Healthcare Act, 2017 (replaced the Mental Health Act, 1987): rights-based and capacity-based — right to access affordable mental healthcare, advance directive, nominated representative, Central and State Mental Health Authorities, Mental Health Review Boards, independent/supported admission in place of "reception orders", 72-hour emergency treatment (Section 94), prohibition of chaining, seclusion, unmodified ECT and sterilisation as treatment, insurance parity (Section 21(4)), and Section 115 — a person who attempts suicide is presumed to be under severe stress and is not to be punished, with a duty of care on the government (the general offence of attempted suicide was not re-enacted in the Bharatiya Nyaya Sanhita, 2023, in force from 1 July 2024).
• Other law and programmes: Rights of Persons with Disabilities Act, 2016 — mental illness is a specified disability, benchmark 40%, certified using IDEAS; NMHP (1982) and DMHP (1996) as the delivery vehicle; POCSO and JJ Act duties in child cases; fitness to stand trial and insanity defence (now under BNS; formerly IPC Section 84).

Key points

• MSE - the core examination in psychiatry; insight and risk assessment must never be omitted.
• Delusion vs hallucination - false belief vs perception without stimulus; obsession is resisted and ego-dystonic.
• Schizophrenia - ≥1 month (ICD-11); positive, negative, cognitive and catatonic domains; negative symptoms cause disability.
• Clozapine - only for treatment resistance (two failed adequate trials); mandatory ANC monitoring for agranulocytosis.
• EPS vs metabolic trade-off - typicals cause more EPS, atypicals more weight gain and dysglycaemia.
• Depression - ≥2 weeks; SSRI first line; continue 6-9 months after remission to prevent relapse.
• Mania - ≥1 week; stop antidepressants, use antipsychotic ± lithium/valproate.
• Lithium - narrow index, 12-hour trough level, monitor TSH, creatinine and calcium; toxic with dehydration, NSAIDs, thiazides.
• Valproate - avoid in women of childbearing potential (neural tube and neurodevelopmental risk).
• ECT - fastest treatment for severe suicidal depression and catatonia; unmodified ECT is illegal in India.
• OCD - high-dose SSRI for 10-12 weeks plus exposure and response prevention.
• Delirium vs dementia - acute, fluctuating, clouded consciousness vs chronic, progressive, clear consciousness.
• Thiamine before glucose in any alcohol-dependent patient, to prevent Wernicke's encephalopathy.
• Delirium tremens - 48-72 h after the last drink; benzodiazepine-based regimen, not antipsychotic alone.
• OST - buprenorphine-naloxone or methadone is maintenance treatment for opioid dependence, not a "substitute addiction".
• NMS vs serotonin syndrome - rigidity and hyperthermia with raised CK vs clonus, hyperreflexia and diarrhoea.
• MHCA 2017 - advance directive, nominated representative, Review Boards, insurance parity, Section 115 on suicide attempt.
• NMHS 2015-16 - 10.6% current prevalence in adults, treatment gap 70-90%; DMHP and Tele-MANAS (14416) close it.

Formulas and examples

Example 1 - quantifying alcohol intake. A 42-year-old man drinks one "quarter" (180 mL) of whisky, 42.8% ABV, daily.

• Pure ethanol volume = 180 × 0.428 = 77.0 mL; mass = 77.0 × 0.789 ≈ 60.8 g/day.
• UK units = 77.0 ÷ 10 ≈ 7.7 units/day (≈54 units/week) — far above low-risk limits, and consistent with dependence.
• He is admitted after 14 hours without alcohol with tremor, BP 160/100, pulse 112. Plan: symptom-triggered chlordiazepoxide (e.g. 25 mg q6h, tapered over 5-7 days), thiamine 100 mg IM/IV TDS before any dextrose, fluids and electrolytes, then naltrexone 50 mg/day with relapse-prevention counselling once liver function allows.

Example 2 - antipsychotic load. A patient receives olanzapine 20 mg/day plus haloperidol 10 mg/day (equivalences: olanzapine 5 mg = 100 mg CPZ; haloperidol 2 mg = 100 mg CPZ).

• Olanzapine: (20 ÷ 5) × 100 = 400 mg CPZ-eq. Haloperidol: (10 ÷ 2) × 100 = 500 mg CPZ-eq.
• Total = 900 mg/day CPZ-equivalent — a high load from polypharmacy. Rational step: taper haloperidol off, keep one agent near 300-500 mg CPZ-eq, and review in 4 weeks.

Example 3 - lithium titration. A 65 kg woman with bipolar I on lithium 600 mg/day has a 12-hour trough of 0.45 mEq/L; target maintenance 0.8 mEq/L.

• New dose = 600 × (0.8 ÷ 0.45) = 1,067 mg/day → prescribe a practical 1,050 mg/day (450 mg morning + 600 mg night, using 300/150 mg tablets) and recheck the level after 5-7 days (about 5 half-lives).
• Counsel: steady salt and fluid intake, avoid NSAIDs, report vomiting/diarrhoea, pre-pregnancy counselling.

Example 4 - QTc before continuing an antipsychotic. ECG shows QT = 420 ms at a heart rate of 96/min.

• RR = 60 ÷ 96 = 0.625 s; √0.625 = 0.7906.
• QTc = 420 ÷ 0.7906 ≈ 531 ms — above 500 ms, so stop the offending drug (e.g. high-dose haloperidol or ziprasidone), correct K⁺ and Mg²⁺, switch to a lower-risk agent such as aripiprazole, and repeat the ECG.

Example 5 - scoring and benefit. A patient scores PHQ-9 = 17 (items 0-3, maximum 27) → moderately severe depression, an indication for pharmacotherapy and/or psychotherapy. If an SSRI gives a 50% response rate against 30% on placebo: ARR = 0.50 − 0.30 = 0.20, NNT = 1 ÷ 0.20 = 5 — five patients treated for one extra responder.

Where it is used

• District Mental Health Programme clinics, medical college psychiatry OPDs and general hospital psychiatric units — screening and managing depression, psychosis, epilepsy comorbidity and substance use.
• De-addiction centres and NDPS-licensed OST clinics (NIMHANS Bengaluru, AIIMS NDDTC Ghaziabad, state-run centres) — detoxification, buprenorphine/methadone maintenance, relapse prevention.
• Primary care and family medicine — somatic presentations of depression and anxiety, brief intervention for alcohol, counselling on adherence; Ayushman Bharat health and wellness centres include mental health in the package.
• Emergency and ICU work — delirium, deliberate self-harm and poisoning, withdrawal states, NMS, catatonia, capacity and consent decisions under the MHCA, 2017.
• Tele-MANAS (14416), school and college counselling, corporate EAPs and occupational health — tele-counselling, triage and referral roles for interns and junior doctors.
• Pharmacovigilance, clinical research and medico-legal work — CNS drug trials, adverse-event coding, disability certification using IDEAS, fitness-to-stand-trial and insanity-defence opinions.

Interview questions

• Q: How do you distinguish delirium from dementia at the bedside? A: Delirium is acute in onset, fluctuates, clouds consciousness and grossly impairs attention; dementia is chronic, progressive, with clear consciousness and relatively preserved attention early.
• Q: Which single drug should be given before intravenous glucose in an alcohol-dependent patient and why? A: Parenteral thiamine, because a glucose load in a thiamine-deficient patient can precipitate Wernicke's encephalopathy.
• Q: When is clozapine indicated? A: Schizophrenia that has not responded to two antipsychotics given at adequate dose and duration; it needs regular neutrophil counts because of agranulocytosis risk.
• Q: How long should an antidepressant be continued after the patient recovers? A: At least 6-9 months after remission for a first episode, and years or indefinitely with recurrent episodes — stopping early is the commonest cause of relapse.
• Q: What is the difference between NMS and serotonin syndrome? A: NMS develops over days with lead-pipe rigidity, hyperthermia and a high CK after antipsychotics; serotonin syndrome develops within hours with clonus, hyperreflexia, agitation and diarrhoea after serotonergic drugs.
• Q: Does asking about suicide increase the risk? A: No — direct, specific enquiry about ideas, intent, plan and means is safe, is the only way to assess risk, and often brings relief.
• Q: What does the Mental Healthcare Act, 2017 say about a suicide attempt? A: Section 115 presumes the person was under severe stress, exempts them from punishment and places a duty on the government to provide care and rehabilitation.
• Q: Why is valproate avoided in young women? A: It carries high teratogenic risk (neural tube defects) and a 30-40% risk of neurodevelopmental impairment in exposed children, so it is used only when no alternative works and contraception is secure.
• Q: A patient on risperidone develops restlessness and cannot sit still — what is it and how do you treat it? A: Akathisia; reduce the dose or switch, and treat with propranolol or a short course of a benzodiazepine (an anticholinergic helps less than in dystonia).
• Q: What are the indications for ECT? A: Severe depression with suicidal risk or food refusal, catatonia, treatment-resistant mania or psychosis, and puerperal psychosis — given only in modified form with anaesthesia and a muscle relaxant.
• Q: First-rank symptoms — are they diagnostic of schizophrenia? A: No; they are suggestive but occur in mania, psychotic depression and organic psychoses, and neither ICD-11 nor DSM-5 gives them special weight.
• Q: A 19-year-old has had abrupt-onset florid psychosis for 10 days after a stressor. Your diagnosis? A: Acute and transient psychotic disorder — common in India, treated with a short antipsychotic course, and usually with full recovery; review the diagnosis if it persists beyond a month.

Common mistakes

• Diagnosing a psychiatric disorder without excluding organic and substance causes — thyroid disease, B12 deficiency, epilepsy, steroids, cannabis.
• Describing symptoms instead of performing a structured MSE, and omitting insight, judgement and risk assessment in the exam case.
• Starting an antidepressant in a bipolar patient without a mood stabiliser, then calling the resulting mania "non-response".
• Judging an antipsychotic or antidepressant to have failed before 4-6 weeks at an adequate dose, and piling on a second drug (polypharmacy with a high CPZ-equivalent load).
• Treating delirium tremens with haloperidol alone, or withholding benzodiazepines because of "sedation risk".
• Calling any false belief a delusion without checking its cultural context, or labelling a resisted intrusive thought a delusion rather than an obsession.
• Quoting lithium levels from a non-trough sample, or continuing the usual dose during vomiting, diarrhoea or NSAID use.
• Forgetting the legal frame — capacity, nominated representative, advance directive and documentation of consent under the Mental Healthcare Act, 2017.

Related topics

Clinical history taking and physical examination · Internal medicine: gastrointestinal, renal and endocrine diseases · Pharmacology of CNS drugs · Community medicine and national health programmes · Forensic medicine and medical jurisprudence · Neurology: seizures and cognitive disorders