Psychotropic Prescribing in Older Adults

Psychotropic prescribing in older adults covers antidepressants, antipsychotics, anxiolytics, hypnotics and mood stabilisers. These drugs carry high risk of falls, fracture, delirium, hyponatraemia, QT prolongation, bleeding and cognitive decline, so each prescription needs a clear target, a start dose lower than in younger adults, and a planned review. Antipsychotics carry a boxed warning for increased mortality in people with dementia, with risk about 1.6 to 1.7 times that of placebo.

Assessment. Before starting, exclude pain, infection, constipation, retention, thirst, delirium and drug causes. Record baseline ECG for QTc, sodium, weight, blood pressure and fall history.

Suicide risk. Older men have the highest rates. Assess risk in every depressive illness.

Depression. Sertraline 25 mg orally once daily for 1 week, then 50 mg, titrated by 25 to 50 mg every 2 to 4 weeks, usual maximum 100 mg daily. Judge response at 4 to 6 weeks and continue for at least 12 months after remission. Halve the dose or lengthen the interval in hepatic impairment.

Alternative. Mirtazapine 7.5 to 15 mg orally at night, maximum 45 mg daily, useful with insomnia and poor appetite. Clearance falls by about 30% when creatinine clearance is under 40 mL/min.

Avoid. Tricyclic antidepressants, paroxetine, citalopram over 20 mg daily and escitalopram over 10 mg daily at age 65 or over because of QT effects.

Anxiety. Sertraline 25 mg orally once daily for 1 week, then 50 mg, with the same titration and maximum. Avoid benzodiazepines; if unavoidable, lorazepam 0.5 mg orally up to twice daily for no more than 2 weeks.

Insomnia. Non-drug measures first. Melatonin prolonged-release 2 mg orally nightly for up to 13 weeks. Avoid benzodiazepines and Z-drugs.

Behavioural symptoms in dementia. Use only for severe distress or danger after non-drug measures. Risperidone 0.25 mg orally at night, increased by 0.25 mg no faster than every 3 to 7 days, usual effective dose 0.5 to 1 mg daily, maximum 2 mg daily. Reassess at 6 weeks and attempt withdrawal by 12 weeks.

Parkinson disease or Lewy body dementia. Quetiapine 12.5 to 25 mg orally at night, usual maximum 100 mg daily. Avoid haloperidol, risperidone and olanzapine.

Lithium. Specialist-led only. Levels are taken 12 hours after the dose, with a lower range of 0.4 to 0.8 mmol/L preferred. Toxicity is likely with ACE inhibitors, NSAIDs, thiazide and loop diuretics, or dehydration.

Special groups. Hyponatraemia occurs mostly within the first 2 to 4 weeks of an SSRI, and risk is greater with diuretics and low body weight. Combine an SSRI with an anticoagulant or NSAID only with a gastroprotective drug such as omeprazole 20 mg orally once daily.

Monitoring. Check sodium at baseline and at 2 and 4 weeks after starting or increasing an SSRI. Repeat ECG after dose increases of QT-prolonging drugs. For antipsychotics record weight, glucose, lipids, extrapyramidal signs, lying and standing pressure and sedation.

Stop rules. Stop or change an SSRI if sodium is under 130 mmol/L. Stop or reduce a QT-prolonging drug if QTc is over 500 ms or has risen by over 60 ms.

Review. Review at 2 weeks, 4 to 6 weeks and then every 3 months.

Stopping. Taper SSRIs over at least 4 weeks to avoid discontinuation symptoms. Taper benzodiazepines by 10% to 25% every 2 to 4 weeks. Withdraw antipsychotics by 25% to 50% every 1 to 2 weeks after 3 months of stability.

Referral and escalation. Refer to old-age psychiatry for psychosis, suicidal thinking, bipolar illness, depression not responding after two adequate courses, or when an antipsychotic is needed beyond 12 weeks.