Psychopharmacology, Emergency Psychiatry & Somatic Therapies

Psychopharmacology and somatic therapies represent essential biological interventions in psychiatric nursing. Because psychotropic medications manipulate central neurotransmitter receptors—frequently possessing narrow therapeutic indices and profound physiological side effects—nursing officers bear statutory and clinical responsibility for dosage titration, adverse effect surveillance, emergency management, and client education.

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1. Antipsychotics (Neuroleptics)

Antipsychotic agents are primarily indicated for schizophrenia, schizoaffective disorder, bipolar mania, and psychotic depression. They are categorized into First-Generation (Typical) and Second-Generation (Atypical) classes.

First-Generation Antipsychotics (FGAs / Typicals)

• Pharmacological Mechanism: Potent post-synaptic antagonism of central Dopamine D2 receptors, particularly along the mesolimbic pathway, effectively suppressing positive psychotic symptoms.
• Classification by Potency:
  • High-Potency FGAs: Haloperidol, Fluphenazine, Trifluoperazine. Marked affinity for D2 receptors; high risk of Extrapyramidal Symptoms (EPS), low anticholinergic, antihistaminic, and anti-adrenergic side effects.
  • Low-Potency FGAs: Chlorpromazine, Thioridazine. Lower affinity for D2 receptors; lower risk of EPS, but marked sedation (H1 blockade), postural/orthostatic hypotension (alpha-1 blockade), and anticholinergic toxicity (M1 blockade).

Extrapyramidal Symptoms (EPS) & Adverse Motor Reactions

Blockade of dopamine D2 receptors in the nigrostriatal tract creates an acute deficiency of dopamine relative to acetylcholine, producing four distinct movement disorders:

                    CHRONOLOGICAL SPECTRUM OF EPS & NMS
  ┌────────────────────────────────────────────────────────────────────────┐
  │ 1. ACUTE DYSTONIA      │ Hours to 5 days  │ Spasms, torticollis, crisis│
  │ 2. AKATHISIA           │ Days to weeks    │ Motor restlessness, pacing │
  │ 3. PARKINSONISM        │ Weeks to months  │ Tremor, rigidity, shuffling│
  │ 4. TARDIVE DYSKINESIA  │ Months to years  │ Irreversible chorea of face│
  │ ★ NEUROLEPTIC MALIGNANT SYNDROME (NMS): Fever + Lead-Pipe Rigidity     │
  └────────────────────────────────────────────────────────────────────────┘

1. Acute Dystonia

• Onset: Within hours to 5 days of initiation or dosage increase (often seen in young males receiving high-potency parenteral haloperidol).
• Clinical Signs: Sudden, painful, sustained involuntary contractions of skeletal muscle groups:
  • Torticollis / Retrocollis: Severe spastic twisting or backward arching of the neck.
  • Oculogyric Crisis: Involuntary, fixed, upward deviation of the eyes into the forehead.
  • Opisthotonos: Severe spastic hyperextension of the entire spine and neck.
  • Laryngeal-Pharyngeal Dystonia: Spasm of vocal cords and tongue protrusion producing acute airway obstruction (life-threatening emergency).
• Emergency Nursing Intervention: Immediately administer a fast-acting parenteral anticholinergic: Promethazine (25–50 mg IM/IV), Diphenhydramine (50 mg IM/IV), or Benztropine (1–2 mg IM/IV). Spasms terminate within 5 to 15 minutes.

2. Akathisia

• Onset: Develops within days to weeks (5 to 60 days).
• Clinical Signs: A subjective, intolerable sensation of internal motor restlessness paired with objective physical movements: continuous pacing, inability to sit or stand still, shifting weight from foot to foot, rocking back and forth. Critical Nursing Warning: Frequently misdiagnosed as worsening psychotic agitation, leading to fatal dose escalations.
• Treatment of Choice: First-line therapy is a central beta-adrenergic blocker: Propranolol (20–80 mg/day) or short-acting benzodiazepines (Lorazepam). Anticholinergics are substantially less effective.

3. Pseudoparkinsonism (Drug-Induced Parkinsonism)

• Onset: Develops within weeks to months (5 to 90 days).
• Clinical Signs: The classic clinical tetrad: resting coarse tremor ("pill-rolling"), cogwheel or lead-pipe rigidity, bradykinesia/akinesia (mask-like facial expression, lack of spontaneous blinking), and a stooped, festinating, shuffling gait with drooling (sialorrhea).
• Treatment: Central oral anticholinergics: Trihexyphenidyl (Artane, 2–6 mg/day) or Benztropine.

4. Tardive Dyskinesia (TD)

• Onset: Late onset, developing after months to years of continuous neuroleptic therapy.
• Pathophysiology: Chronic dopamine blockade induces compensatory post-synaptic dopamine receptor supersensitivity and up-regulation in the striatum.
• Clinical Signs: Involuntary, repetitive, choreoathetoid, rhythmic movements of the orofacial and lingual musculature: continuous tongue protrusion ("fly-catcher tongue"), lip smacking, puckering, grimacing, rapid eye blinking, chewing motions, and choreic pelvic thrusting.
• Critical Clinical Principles:
  • TD is frequently permanent and irreversible once established.
  • Anticholinergic drugs worsen TD and are strictly contraindicated.
  • Routine screening every 3 to 6 months using the Abnormal Involuntary Movement Scale (AIMS).
  • Management: Discontinue or taper offending typical agent; switch to an atypical antipsychotic with low D2 binding affinity (Clozapine or Quetiapine); administer VMAT2 inhibitors (Valbenazine, Deutetrabenazine).

Neuroleptic Malignant Syndrome (NMS)

A rare, idiosyncratic, life-threatening complication of dopamine receptor antagonism carrying a mortality of 10% to 20%:

• Clinical Tetrad:
  1. Hyperthermia: Sudden, unexplained high fever, typically > 38°C (> 100.4°F) escalating up to 41°C (105.8°F).
  2. Severe Muscle Rigidity: Generalized, severe "lead-pipe" rigidity and generalized hyporeflexia.
  3. Altered Mental Status: Confusion, agitation, mutism, delirium, progressing rapidly to stupor and coma.
  4. Autonomic Instability: Marked tachycardia (>120 bpm), labile and fluctuating blood pressure, profuse diaphoresis, tachypnea, and urinary incontinence.
• Diagnostic Laboratory Biomarkers: Massive elevation of serum Creatine Kinase (CK / CPK > 1,000 to 50,000 IU/L) due to extensive rhabdomyolysis; leukocytosis (WBC 15,000–30,000/μL); elevated serum transaminases; and myoglobinuria (high risk of acute renal tubular necrosis and renal failure).
• Immediate Emergency Nursing Protocols:
  • Immediately STOP all antipsychotic medications!
  • Transfer patient urgently to the Intensive Care Unit (ICU).
  • Aggressive physical cooling: Hypothermic cooling blankets, ice packs placed in axillae and groin, chilled intravenous normal saline infusions.
  • Correct dehydration and flush myoglobin via aggressive IV hydration.
  • Pharmacological Antidotes:
    • Dantrolene Sodium (1–2.5 mg/kg IV bolus): Skeletal muscle relaxant that blocks calcium release from the sarcoplasmic reticulum, relieving rigidity and hyperthermia.
    • Bromocriptine Mesylate (2.5–10 mg PO/NG three times daily): Dopamine D2 receptor agonist that overcomes central neuroleptic dopamine blockade.

Second-Generation Antipsychotics (SGAs / Atypicals)

• Mechanism of Action: Dual antagonism: block post-synaptic Dopamine D2 receptors and Serotonin 5-HT2A receptors. Serotonin antagonism disinhibits dopamine release in the nigrostriatal and prefrontal pathways, significantly reducing EPS risk and improving negative symptoms.
• Representative Agents: Clozapine, Olanzapine, Risperidone, Quetiapine, Aripiprazole (partial D2 agonist), Ziprasidone.
• Major Adverse Profile: Metabolic Syndrome:
  • Markedly elevated risk of substantial weight gain, hyperlipidemia, insulin resistance, and new-onset Type 2 Diabetes Mellitus (highest with Olanzapine and Clozapine).
  • Nursing monitoring: Baseline and periodic BMI, waist circumference, fasting plasma glucose, and lipid profiles.

Clozapine: Clinical Pearls & Mandatory Surveillance Protocols

Clozapine is the gold-standard, most effective antipsychotic for treatment-resistant schizophrenia (failure of at least two adequate trials of other antipsychotics) and the only agent proven to reduce suicide risk in schizophrenia. It causes virtually zero EPS and does not elevate prolactin.

                 CLOZAPINE MANDATORY HEMATOLOGICAL PROTOCOL
  ┌────────────────────────────────────────────────────────────────────────┐
  │ 1. Risk: Life-threatening Agranulocytosis (ANC < 500 / μL)              │
  │ 2. Mandatory Absolute Neutrophil Count (ANC) Surveillance:              │
  │    - Weekly for the first 6 months                                      │
  │    - Every 2 weeks for the next 6 months                                │
  │    - Every 4 weeks thereafter for the duration of therapy               │
  │ 3. Discontinuation Thresholds:                                          │
  │    - If ANC < 1,000 / μL: Discontinue Clozapine immediately!            │
  │ 4. Client Education: Report fever, chills, sore throat, mouth ulcers    │
  └────────────────────────────────────────────────────────────────────────┘

• Other Serious Clozapine Risks: Dose-dependent seizure threshold reduction, fatal myocarditis/cardiomyopathy, severe orthostatic hypotension, and severe gastrointestinal hypomotility (life-threatening paralytic ileus).

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2. Antidepressant Pharmacotherapy

Antidepressants modulate central monoaminergic neurotransmission (serotonin, norepinephrine, dopamine):

1. Selective Serotonin Reuptake Inhibitors (SSRIs)

• Agents: Fluoxetine, Sertraline, Escitalopram, Citalopram, Paroxetine.
• Mechanism: Selectively block the presynaptic serotonin transporter (SERT), inhibiting reuptake and prolonging 5-HT availability in the synaptic cleft. First-line therapy for depression, panic disorder, OCD, and PTSD.
• Adverse Effects: Nausea, diarrhea, insomnia, agitation, and sexual dysfunction (delayed ejaculation, anorgasmia in 30% to 50% of clients). Fluoxetine has an exceptionally long elimination half-life (active metabolite norfluoxetine half-life ~7 to 15 days).

Serotonin Syndrome (Serotonergic Toxicity)

A life-threatening, hyper-serotonergic crisis caused by drug interactions combining serotonergic agents (e.g., SSRIs + MAOIs, SSRIs + Tramadol, SSRIs + Linezolid, SSRIs + St. John's Wort):

• Hunter Serotonin Toxicity Diagnostic Criteria: Characterized by a clinical triad:
  1. Neuromuscular Excitation: Hyperreflexia, sustained or inducible clonus (ankle clonus), tremor, shivering, myoclonus, bilateral Babinski signs.
  2. Autonomic Reactivity: Hyperthermia, tachycardia, diaphoresis, flushing, gastrointestinal hypermotility (hyperactive bowel sounds, diarrhea).
  3. Altered Mental Status: Agitation, hypomania, confusion, hallucinations.
• Crucial Differential Diagnosis: Serotonin Syndrome (SS) vs. NMS:
  • SS features hyperreflexia, tremor, and clonus; onset is rapid (within hours of ingestion); bowel sounds are hyperactive.
  • NMS features lead-pipe muscle rigidity and hyporeflexia; onset is gradual over days to weeks; bowel sounds are normal or decreased.
• Management: Discontinue all serotonergic agents, provide active cooling and hydration, administer benzodiazepines for agitation, and administer the serotonin receptor antagonist Cyproheptadine.
• Mandatory Washout Interval: A mandatory 2-week washout period (and at least 5 weeks for Fluoxetine) must elapse between discontinuing an SSRI and initiating an MAOI to prevent fatal Serotonin Syndrome.

2. Tricyclic Antidepressants (TCAs)

• Agents: Amitriptyline, Imipramine, Clomipramine, Nortriptyline.
• Mechanism: Inhibit reuptake of norepinephrine and serotonin. Also non-selectively block histamine H1, muscarinic acetylcholine, and alpha-1 adrenergic receptors.
• Adverse Effects: Severe anticholinergic effects (dry mouth, blurred vision, cycloplegia, urinary retention, constipation), orthostatic hypotension, and sedation.
• Fatal Cardiotoxicity in Overdose: TCAs block cardiac fast sodium channels, causing life-threatening intraventricular conduction delays: QRS widening (>100 ms), prolonged QTc, ventricular tachycardia, and cardiac arrest. Antidote for TCA cardiotoxicity: Intravenous Sodium Bicarbonate (alkalinizes serum, dislodging the drug from cardiac sodium channels).

3. Monoamine Oxidase Inhibitors (MAOIs)

• Agents: Phenelzine, Tranylcypromine, Isocarboxazid, Selegiline.
• Mechanism: Irreversibly inhibit monoamine oxidase enzymes (MAO-A and MAO-B), preventing the metabolic breakdown of norepinephrine, serotonin, and dopamine.
• The Hypertensive Crisis (Tyramine Interaction):
  • Ingestion of dietary Tyramine (found in aged cheeses, red wines, draft beers, cured meats, salami, fermented soy sauce, yeast extracts) triggers massive release of stored norepinephrine.
  • Clinical Signs: Sudden, excruciating occipital throbbing headache, palpitations, neck stiffness, marked systolic hypertension (>200 mmHg), and risk of intracranial hemorrhage.
  • Emergency Antidote: Intravenous Phentolamine (alpha-adrenergic antagonist) or sublingual Nifedipine.

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3. Mood Stabilizers & Therapeutic Drug Monitoring

Lithium Carbonate

Lithium is the definitive gold-standard mood stabilizer for acute bipolar mania and maintenance prophylaxis, with documented anti-suicidal properties.

Pharmacokinetics & Renal Handling

Lithium is a monovalent alkali cation handled by the kidneys identically to sodium. Over 95% is eliminated unchanged by renal glomerular filtration, with 80% actively reabsorbed in the proximal convoluted tubules.

                  THE CRUCIAL LITHIUM - SODIUM EQUILIBRIUM
  ┌────────────────────────────────────────────────────────────────────────┐
  │ NORMAL SODIUM INTAKE  ──> Normal renal lithium excretion               │
  │ LOW SODIUM INTAKE     ──> Proximal tubule reabsorbs sodium & LITHIUM   │
  │ DEHYDRATION / SWEAT   ──> Massive lithium retention ──> FATAL TOXICITY │
  │ THIAZIDE DIURETICS    ──> Sodium wasting ──> 40% rise in lithium levels│
  └────────────────────────────────────────────────────────────────────────┘

Therapeutic Drug Monitoring (TDM) Parameters

Lithium possesses an extraordinarily narrow therapeutic range. Serum blood samples must be drawn precisely 12 hours post-evening dose (trough level):

• Acute Mania Therapeutic Range: 0.8 to 1.2 mEq/L (or mmol/L).
• Long-term Maintenance Range: 0.6 to 1.0 mEq/L.
• Toxic Serum Concentration: Toxic signs emerge at levels > 1.5 mEq/L.

Lithium Toxicity Stages & Manifestations

1. Mild Toxicity (1.5 to 2.0 mEq/L):
   • Gastrointestinal distress: Persistent nausea, vomiting, severe diarrhea.
   • Neurological: Coarse hand tremors (differentiated from benign, fine intention tremors seen at therapeutic levels), muscle weakness, lethargy, drowsiness.
2. Moderate Toxicity (2.0 to 2.5 mEq/L):
   • Coarse tremors, marked ataxia, dysarthria (slurred speech), hyperreflexia, muscle twitching, fasciculations, prominent confusion, and delirium.
3. Severe Toxicity (>2.5 mEq/L):
   • Generalized tonic-clonic seizures, cardiac arrhythmias, hypotension, peripheral circulatory collapse, oliguria, acute renal failure, stupor, coma, and death.
   • Definitive Treatment for Severe Toxicity: Hemodialysis is used for severe toxicity. Nursing texts quote levels above 2.5 mEq/L; the EXTRIP toxicology criteria recommend it above 4.0 mEq/L with impaired kidney function, or at any level with reduced consciousness, seizures, or dysrhythmias.

Essential Nursing Interventions for Lithium Therapy

• Fluid & Salt Maintenance: Instruct the client to consume 2 to 3 liters of fluid daily and maintain a consistent, normal dietary salt intake. The client must never initiate a low-sodium diet, undergo unmonitored fasting, or take over-the-counter loop/thiazide diuretics.
• Avoid NSAIDs: Ibuprofen, indomethacin, and naproxen decrease renal prostaglandin synthesis, reducing lithium clearance and precipitating toxicity. (Paracetamol / Acetaminophen is safe).
• Baseline & Periodic Laboratory Monitoring:
  • Renal Function: Blood Urea Nitrogen (BUN) and Serum Creatinine (risk of nephrogenic diabetes insipidus).
  • Thyroid Function: Serum TSH, Free T4 (lithium inhibits thyroid hormone synthesis and release, causing goiter and hypothyroidism in 10% to 20% of clients).
  • ECG & Serum Electrolytes.

Anticonvulsant Mood Stabilizers

• Sodium Valproate / Divalproex Sodium:
  • Effective for rapid-cycling bipolar disorder and mixed manic episodes.
  • Adverse Effects: Hepatotoxicity (monitor LFTs), acute pancreatitis, thrombocytopenia, alopecia, weight gain, and severe teratogenicity (Neural Tube Defects: spina bifida; contraindicated in pregnancy).
• Carbamazepine:
  • Indicated for acute mania and trigeminal neuralgia.
  • Adverse Effects: Aplastic anemia and agranulocytosis (monitor complete blood counts), Stevens-Johnson Syndrome (SJS) (especially in clients positive for HLA-B*1502 allele), hyponatremia (SIADH), and potent hepatic CYP450 enzyme auto-induction.

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4. Somatic Therapies: Electroconvulsive Therapy (ECT)

Electroconvulsive Therapy is the controlled, artificial electrical induction of a generalized tonic-clonic grand mal seizure for therapeutic psychiatric purposes.

Clinical Indications & Mechanism

• Primary Indications:
  1. Severe Major Depressive Disorder with imminent suicide risk (ECT is the fastest-acting antidepressant intervention in clinical medicine).
  2. Depressive stupor or psychotic depression with severe delusions of guilt/ruin.
  3. Catatonic stupor or catatonic excitement (rapidly reverses life-threatening catatonia).
  4. Treatment-resistant acute mania (exhausted pharmacotherapy options).
  5. Neuroleptic Malignant Syndrome unresponsive to bromocriptine and dantrolene.
• Contraindications: There are no absolute medical contraindications to ECT. The primary major relative contraindication is Increased Intracranial Pressure (ICP) (space-occupying intracranial lesions, recent hemorrhagic stroke) because the seizure transiently spikes cerebral blood flow and ICP. Recent myocardial infarction (<3 months) is also a major cardiovascular risk.
• Seizure Threshold & Duration: The therapeutic electrical stimulus must elicit an adequate generalized tonic-clonic seizure lasting at least 25 to 60 seconds on EEG (or a 20 to 30 second visible peripheral motor seizure). Seizures <15 seconds lack therapeutic efficacy.

Modified ECT Protocol (The Statutory Standard)

Under Section 95 of the Mental Healthcare Act 2017, unmodified ECT is completely illegal. Modified ECT must always be administered under general anesthesia and muscle relaxation:

1. Pre-medication (Anticholinergic): Atropine Sulphate (0.4–0.6 mg IV/IM) or Glycopyrrolate administered 30 minutes pre-procedure to prevent vagally mediated severe bradycardia/asystole and minimize oral/respiratory secretions.
2. Anesthetic Induction Agent: Ultra-short-acting intravenous barbiturate: Methohexital (0.75–1.0 mg/kg IV) or Thiopental / Propofol. Produces rapid loss of consciousness within 30 to 60 seconds.
3. Muscle Relaxant: Succinylcholine Chloride (0.5–1.0 mg/kg IV). Depolarizing neuromuscular blocker that paralyzes all skeletal muscles, preventing violent convulsions, vertebral compression fractures, and joint dislocations while allowing cortical brain seizure activity.
4. Oxygenation: Pre-oxygenation and continuous manual bag-valve-mask ventilation with 100% Oxygen from induction until spontaneous respiratory effort returns.

Nursing Management Across the ECT Continuum

Pre-ECT Nursing Care

• Confirm valid, documented informed consent.
• Ensure strict NPO status for 6 to 8 hours prior to procedure to prevent intra-procedural aspiration.
• Ensure client empties bladder immediately before transfer to prevent involuntary urinary incontinence during seizure.
• Remove all foreign objects: dentures, removable dental bridges, eyeglasses, contact lenses, jewelry, metal hairpins, and tight restrictive clothing.
• Check baseline vital signs and baseline 12-lead ECG.

Intra-ECT Nursing Care

• Insert a soft, padded rubber mouth bite-block immediately prior to electrical discharge to protect teeth and prevent tongue biting.
• Assist the anesthetist in maintaining a patent airway and continuous bag-mask oxygenation.
• Record duration of motor and EEG seizure activity.

Post-ECT Nursing Care

• Position the client in the lateral recovery (side-lying) position to facilitate oral drainage and prevent aspiration.
• Maintain airway patency, suction secretions as needed, and administer oxygen until spontaneous respirations stabilize.
• Monitor vital signs every 15 minutes for the first hour.
• Reorient the client to person, place, and time as consciousness clears.
• Reassurance Regarding Cognitive Deficits: Inform and reassure the client and family that transient retrograde and anterograde amnesia (temporary memory loss and mild post-ictal confusion) is the most common side effect of ECT, which typically resolves spontaneously within several weeks following treatment completion.

5. Clinical Master Matrices

Extrapyramidal Symptoms (EPS) vs. Neuroleptic Malignant Syndrome (NMS)

Lithium Serum Levels, Clinical Presentation & Nursing Interventions Reference