Mental Health Meds on Acute Wards: Antipsychotics, Lithium & More
What every student nurse needs to know — SSRIs, sedatives, monitoring lithium levels, and spotting dangerous reactions before it’s too late.
You will meet patients taking mental health medications on every ward — medical, surgical, elderly care, A&E. Yet these drugs are rarely covered in depth on general placements, leaving students feeling nervous and unprepared. Is a patient’s confusion just delirium — or lithium toxicity? Is their fever infection — or neuroleptic malignant syndrome? Knowing these differences saves lives.
This guide covers the core drug classes you’ll administer most often, what to check before you give them, and the red-flag side effects that demand urgent action — all aligned with NICE guidance and current BNF Chapter 4.
1. National Guidance
Content aligned with: NICE CG178 — Psychosis & Schizophrenia; NICE NG10 — Violence & Aggression (Rapid Tranquillisation); NICE CG90 — Depression; NICE CG185 — Bipolar Disorder; plus MHRA drug safety updates and BNF Chapter 4.
📎 Source: NICE CG178 — Psychosis & Schizophrenia
📎 Source: NICE NG10 — Rapid Tranquillisation
⚠️ Always check local policy. Rapid tranquillisation protocols, lithium target ranges, and formularies vary by trust. When in doubt, consult pharmacy or the on-call mental health team.
2. SSRIs & SNRIs — Antidepressants
Selective Serotonin Reuptake Inhibitors (SSRIs) are first-line for depression and anxiety. They are not instant mood-lifters — full effect takes 4–6 weeks. Patients often stop them early because “they’re not working yet.” Your role is to explain the timeline and support persistence.
| Drug | Key Nursing Points | Notable Risks |
|---|---|---|
| Sertraline 50–200 mg OD | Best tolerated GI profile; safer in cardiac disease. Give in morning to reduce insomnia. | Mild nausea initial 1–2 weeks — usually settles. Sexual dysfunction common long-term. |
| Citalopram / Escitalopram | Once daily, simple regime. QTc prolongation risk — maximum doses apply (citalopram 20mg >65yrs). | Check ECG if high dose or cardiac history. Avoid with other QTc-prolonging drugs — see cardiac meds interactions. |
| Fluoxetine 20–60 mg OD | Long half-life — stays in system for weeks. Less discontinuation reaction if missed doses. | Activating — anxiety may worsen first 2 weeks. Risk in liver impairment. |
| Venlafaxine (SNRI) 75–375 mg BD/MR | Serotonin + noradrenaline — stronger physical effect. BP rises dose-dependently. | ✅ Check BP before every dose increase. Discontinuation reaction severe — never stop abruptly. Taper over months. |
| Mirtazapine 15–45 mg ON | Not SSRI — sedating, increases appetite. Give at night. Good if weight loss or insomnia accompany depression. | Weight gain is common — monitor. Neutropenia rare but serious — report sore throat/fever. |
Critical Safety — Don’t Miss These
- Suicidality risk: Energy returns before mood — patient can now act on thoughts they previously lacked the drive to carry out. Escalate any new/changed self-harm thoughts urgently. Highest risk: first 2–4 weeks, under age 25.
- Serotonin Syndrome: Too much serotonin — usually two drugs combined. Onset rapid (hours–days): confusion, agitation, tremor, clonus, hyperreflexia, fever, sweating, diarrhoea. Stop all serotonergic drugs, inform medics, monitor in HDU if severe. Common triggers: tramadol + SSRI, SSRI + migraine triptans, antidepressant + antidepressant.
- Discontinuation syndrome: Dizziness, “brain zaps,” nausea, headache, anxiety on stopping. Taper slowly over at least 4 weeks (fluoxetine excepted).
- Hyponatraemia (SIADH): Low sodium — confusion, drowsiness, seizures. More common in elderly. Check U&E if patient becomes unwell/confused — see electrolyte monitoring.
3. Lithium — The Narrow Therapeutic Window
Lithium is the gold-standard mood stabiliser for bipolar disorder and recurrent depression. It is also the drug students fear most — and rightly so, because the difference between therapeutic and toxic is tiny. Narrower than any other drug you will give.
- Therapeutic range: 0.6–1.0 mmol/L (maintenance); 0.8–1.2 mmol/L (acute mania)
- Toxic: >1.5 mmol/L — dangerous; >2.0 mmol/L — life-threatening
- When to test: 12 hours POST-dose — not random. Same time each visit
- Steady state: 5–7 days to stabilise after any dose change
- Check frequency: Every 3 months stable; every month dose changes; renal/thyroid function every 6–12 months
Toxicity — Early vs Late Signs
Lithium toxicity creeps up. Early signs = reversible if caught. Late signs = permanent neurological damage or death. Know the progression:
| Stage | Signs & Symptoms | Action |
|---|---|---|
| Mild (<1.5) | Fine tremor → coarse tremor, diarrhoea, vomiting, drowsiness, muscle weakness, polyuria | Stop lithium, check level, review U&E. Rehydrate IV if dehydrated. Often triggered by low sodium/dehydration or NSAID use. |
| Moderate (1.5–2.0) | Confusion, ataxia, blurred vision, increasing drowsiness, large output dilute urine | Urgent lithium level + U&E. IV fluids. Medical review. May need HDU monitoring. |
| Severe (>2.0) | Seizures, coma, renal failure, hypotension, arrhythmias, permanent brain damage | Emergency. Stop drug. IV fluids. Lithium levels every 4–6 hours. May require haemodialysis. |
What Pushes Lithium Up — The “Risk Checklist”
- Dehydration: Fever, diarrhoea/vomiting, heat, poor oral intake → body conserves sodium → reabsorbs lithium too → levels rocket. Acute illness plan essential — “sick day rules” like steroids
- Drug interactions — memorise these:
- NSAIDs (ibuprofen, naproxen) → raise lithium by ~50% — use paracetamol only for pain
- Diuretics (furosemide, bendroflumethiazide) → sodium loss → lithium retention — see heart failure meds
- ACEi/ARBs (ramipril, losartan) → similar effect — dose reduction often needed
- Sodium changes: Low salt diet or excess sweating → lithium up; high salt → lithium down → mood destabilises
- Renal decline: Lithium is 100% renally cleared. eGFR falls → dose falls. Long-term lithium can cause nephrogenic diabetes insipidus — watch for excessive thirst/urine output
Long-Term Monitoring — Beyond the Level
Lithium affects more than just mood. Annual checks must include:
- Thyroid function: Hypothyroidism in ~10–15% — can look like depression. Tired, weight gain, cold intolerance. Check TSH annually
- Renal function: eGFR — gradual decline common. Dose adjust or switch if <45
- Weight, BP, electrolytes: Baseline and regular
4. Antipsychotics — Typical vs Atypical
These treat psychosis (hallucinations, delusions) but also mania, severe agitation, and refractory anxiety. “Typical” = older; “atypical” = newer, different side-effect profile. Neither is “better” — each patient responds differently.
| Drug | Type | Key Effects & Risks |
|---|---|---|
| Quetiapine 25–800 mg | Atypical | Sedation = main effect — often used off-licence for anxiety/sleep. Postural hypotension (slow dose titration). Metabolic risk — weight, glucose, lipids. Give at night. |
| Olanzapine 2.5–20 mg | Atypical | Highly effective BUT highest weight gain/diabetes risk. Monitor HbA1c. Orodispersible tablets available — place on tongue, no water needed. Sedating. |
| Risperidone 0.5–6 mg | Atypical | Prolactin elevation — breast swelling, galactorrhoea, period changes. EPS at higher doses. Long-acting injection (LAI) option available. |
| Aripiprazole 5–30 mg | Atypical (partial agonist) | Less weight gain/metabolic risk. Akathisia = inner restlessness — common, distressing, often mistaken for anxiety. Can cause insomnia — give morning. |
| Haloperidol 0.5–20 mg | Typical | High EPS risk — dystonia, parkinsonism, tremor. QTc prolongation — ECG needed before IM use. Lower metabolic burden but movement risks high. |
Movement Disorders — EPS & NMS
Extrapyramidal symptoms (EPS) result from dopamine blockade. They can happen at any time — watch for them on every shift:
| Condition | Signs | Action |
|---|---|---|
| Acute Dystonia — hours–days | Spasm: neck twisted, eyes fixed upward, tongue/throat tight — terrifying for patient | Emergency — give procyclidine IM/IV. Reduce/stop antipsychotic. Document and inform prescriber. |
| Akathisia — days–weeks | Inner restlessness — can’t sit still, pacing, foot-tapping. NOT anxiety — worsens with drug, improves on propranolol | Distress is real — patient isn’t “just fidgeting.” Dose reduction or switch needed. Propranolol helps. |
| Parkinsonism — weeks–months | Tremor, shuffling gait, rigidity, mask-like face, drooling. Looks like Parkinson’s but drug-induced | Reduce dose or change drug. Anticholinergics (procyclidine) help but carry own risks. |
| Tardive Dyskinesia — months–years | Involuntary lip-smacking, chewing, tongue darting, finger movements. Often irreversible | Prevent — use lowest effective dose. Refer to psychiatrist promptly. |
| Neuroleptic Malignant Syndrome (NMS) — rare but deadly | FEVER: Fever, Encephalopathy, Vitals unstable, Elevated enzymes (CK), Rigidity. Onset days–weeks | STOP drug. Urgent medical review. ITU admission often needed. Dantrolene/bromocriptine in specialist settings. Mortality ~10%. |
Clozapine — The Last Resort
Used when two or more antipsychotics fail. Highly effective but carries unique, life-threatening risks — never miss a blood test:
- Agranulocytosis: White cell count drops → no infection defence. Fatal if missed. Weekly FBC first 18 weeks → fortnightly → monthly. Withhold dose and call doctor immediately if WCC <3.5 or neutrophils <2.0. Sore throat, fever, mouth ulcers = red flag
- Myocarditis: First 2 months — fever + chest pain + dyspnoea + fatigue. ECG/troponin urgently
- Hypersalivation: Excess drooling — common, socially distressing, not dangerous
- Bowel obstruction: Severe constipation — can progress to paralytic ileus. Monitor bowel chart aggressively
5. Benzodiazepines & Sedatives — Short-Term Only
Lorazepam, diazepam, temazepam — these work fast. They are also highly addictive. NICE recommends maximum 2–4 weeks continuous use for anxiety/insomnia. Beyond that, dependence and tolerance are guaranteed.
On Acute Wards — Rapid Tranquillisation
When de-escalation fails and patient at risk of harm. NICE NG10 recommends oral options first, then IM if needed:
- Oral PRN: Lorazepam 1–2 mg; promethazine 25–50 mg; quetiapine 50–100 mg
- IM options (NICE): Lorazepam 1–2 mg — or — Haloperidol 5 mg + promethazine 50 mg. Olanzapine IM = alternative but NEVER within 1hr of benzodiazepine IM
- Post-administration monitoring: NEWS2 observations every 15–30 mins. Airway priority — sedation can deepen unexpectedly. Do NOT leave patient alone
Withdrawal — Don’t Stop Abruptly
Short-acting drugs (lorazepam) = harder to come off. Long-acting (diazepam) = easier to taper. Seizure risk if stopped cold turkey. Taper over weeks to months depending on duration of use.
6. Your Admission Medication Reconciliation Checklist
Patients admitted to your ward rarely bring full psychiatric notes. You are their safety net — ask these questions on admission:
- What mental health drugs do you take? — check GP list vs what they say vs what they brought in
- Are you on lithium? When was your last blood level? What was the result?
- Any depots/injections? — when due? Who administers them?
- Any clozapine? — which clinic? Next blood test date? Registration number?
- Have you missed doses recently? — risk of withdrawal or relapse
- Do you take anything for anxiety/sleep that isn’t on this list? — hidden benzodiazepine dependence common
- Any sick-day plan for lithium/steroids? — see steroid safety guide
- Any side effects you’ve been putting up with? — weight gain, tremor, restlessness, sexual effects all under-reported
- When did you last see your psychiatrist/Care Coordinator? — who to contact if concerns
- Any advance statements or crisis plans? — check for documented preferences
7. Special Considerations — The Acute Context
- Delirium vs psychiatric: New confusion = sepsis, dehydration, drugs, hypoxia until proven otherwise. Don’t just “sedate the confusion” — investigate it
- NBM/NPO status: Psych meds MUST still be given unless absolute contraindication. Orodispersible, liquid, or injection alternatives exist — ask pharmacy
- Surgery & withdrawal: Opioids + psych meds = additive sedation risk. Benzodiazepine withdrawal post-op = delirium, seizures. Plan cover pre-operatively with anaesthetist
- Overdose risk: Tricyclics are the most dangerous in overdose (cardiac arrest risk). SSRIs much safer but still monitor. Only give small quantities at discharge where concern exists
- Smoking cessation: Tobacco smoke induces liver enzymes — stop smoking and antipsychotic levels RISE. Dose reduction often needed. Monitor closely