Pharmacotherapy of Functional Mental Illness in the Elderly.

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Pharmacotherapy of Functional Mental Illness in
the Elderly.

• Virupakshi Jalihal
• Locum Consultant Psychiatrist
• Cornwall Partnership NHS Foundation Trust
• 20 June 2011

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• Prevalence of many illnesses increases with age
• Generalisation of evidence to the elderly
  patients - Elderly individuals often excluded in
  trials

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Pharmacokinetics in the Elderly

• Bioavailability - absorption may be poor
• Increased half life - altered metabolic rate and
  reduced renal clearance
• Volume of distribution - protein binding
• Increased concentration in brain less efficient
  blood brain barrier

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Pharmacodynamics in the Elderly

• Drug interactions
• Narrower therapeutic window side
  effects/toxicity
• Treatment resistance - reduction in receptor
  density

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Choice of Psychotropic Medication

• Presence of coexisting physical illness and/or
  cognitive impairment
• Previous response in the individual and family
  members
• Patient preference
• Clinicians familiarity
• Adequate dose and duration of treatment
• Start low and go slow

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Depression

• Medication associated - psychotropic
  (benzodiazepine buspirone), anti-parkinsonian
  (L-dopa anticholinergics), anticonvulsant
  (carbamazepine phenobarbitone),
  antihypertensive (methyldopa Beta blocker),
  NSAID, steroids, etc..,

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Depression

• Response may take longer up to 12 wks
• SSRI, SNRI, NARI, NaSSA are preferred less
  sedation, postural hypotension, anticholinergic
  side effects. Safer cardiac profile and in
  overdose, lesser effect on seizure threshold
• TCA 2/3 line, anticholinergic side effects,
  lofepramine is preferred TCA
• MAO inhibitors 2/3 line, Moclobomide is
  reversible MAOI preferred. Remember washout
  period if switching, MAOI-gtSSRI is 2 wks SSRI-gt
  MAOI can be up to 5 weeks.

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Depression

• Augmentation lithium in treatment resistance
• ECT severe depression with psychotic symptoms
  and/or psychomotor retardation.

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Bipolar Affective Disorder

• Increase in frequency duration of episodes
• Drug induced - steroids
• Mood stabiliser or antipsychotics
• Atypical antipsychotics preferred
• Decreased GFR risk of lithium toxicity
• Lithium dose may be lower than in adults aim
  for 0.5 mmol/L
• Valproate may be preferred

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Psychosis

• Rule out delirium
• Paraphrenia or schizophrenia
• Paraphrenia needs lower dose of antipsychotic
  medication
• Atypical antipsychotics preferred
• Clozapine is still an option in the elderly
• Avoid drugs with anticholinergic action
  phenothiazines
• Tardive dyskinesia is difficult to treat

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Neurotic disorders

• Anxiety symptoms common in the elderly
• Benzodiazepines commonly used be aware of
  dependence potential and paradoxical agitation
• Buspirone 5HT1a receptor, less side effects but
  is it effective?
• SSRI in OCD, phobia, panic disorder
• Beta blockers for anxiety
• Combine pharmacotherapy with psychological
  approaches.

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Insomnia Sexual dysfunction

• Insomnia is common
• Use hypnotics judiciously
• Sildenafil is an option for erectile dysfunction

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Miscellaneous

• Treatment of coexisting physical and organic
  conditions
• Pharmacotherapy of drug and alcohol dependence
• Aids to improve compliance
• Psychotropics in palliative care
• Withdrawal of medication in those dying

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MCQ/BOF

• Drug that increases lithium level is
• (a) Furosemide
• (b) Propronolol
• (c) Paracetamol
• (d) Mirtazapine
• (e) Salbutamol
• AnsLithium levels are increased by diuretics
  except for acetazolamide. Loop diuretics
  (furosemide) are safer than thiazides.

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• 2. A patient has been on antidepressant but he
  forgets to take his tablets once or twice in a
  week. Which of the following is more suitable for
  him?
• Fluoxetine
• Venlafaxine
• Duloxetine
• Sertraline
• Paroxetine
• AnsFluoxetine has a half-life of 48-72 hours,
  its active metabolite norfluoxetine has a
  half-life of about a week. This will mean slower
  tapering of plasma levels if 1 or 2 doses are
  missed thus avoiding withdrawal symptoms. Some
  even suggest that fluoxetine can be administered
  biweekly or on alternate days.

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• 3. Which of the following is a noradrenaline
  reuptake inhibitor (NARI)?
• (a) Reboxetine
• (b) Paroxetine
• (c) Fluoxetine
• (d) Risperidone
• (e) Agomelatine
• AnsMaprotiline, viloxazine and reboxetine are
  selective noradrenaline reuptake inhibitors.

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• 4. Use of which drug would require a lower dosage
  of ECT?
• (a) Lithium
• (b) Zolpidem
• (c) Valproate
• (d) Lamotrigine
• (e) Diazepam
• Ans Lithium can decrease the seizure threshold
  and the patient may have increased seizure
  duration. All others tend to increase seizure
  threshold and require higher dose of ECT to
  produce an adequate seizure.

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• 5. A depressed patient with a history of CVS
  problems was started by his GP on fluoxetine.
  After few days of treatment he started
  complaining of feeling lethargic with muscle
  aches, and malaise. What is the likely cause?
• (a) Hyponatraemia
• (b) Myocardial infarction
• (c) Delirium
• (d) Heart failure
• (e) Anaemia
• Ans Hyponatraemia is associated with SSRI
  treatment especially in elderly patients.
  Confusion, agitation and lethargy are common
  symptoms.

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• 6. Which of the following is true regarding
  paraphrenia?
• (a) More common in males
• (b) Associated with schizophrenia
• (c) Rarely seen in the elderly
• (d) Need high doses of antipsychotis
• (e) Has good prognosis
• Ans Onset usually gt60 years, more common in
  females (up to 80), 10-20 of adult
  antipsychotic doses, good prognosis.

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Thank you