Pharmaceutical Care of People with Depression

1. Pharmaceutical Care of People with Depression

2. Objectives • Provide an overview of the diagnosis and therapeutic management of depression • Identify key pharmaceutical care needs of this group of patients • Explore ways of positively impacting on the care of this patient population

3. National Programme for Improving Mental Health and Well-being in Scotland September 2003-2006 • Key aims: • Raise awareness and promoting mental health and well-being • Eliminate stigma and discrimination • Prevent suicide • Promote and support recovery

4. Key Facts & Figures • Life-time Prevalence: 1 in 2 women; 1 in 4 men • 30% of above with Major Depressive Illness • >80% treated in primary care • 50-60% of patients respond to 1st line Treatment • 25-30% placebo response in controlled trials • 20-60% of patients respond to switching between class of antidepressant or SSRIs • 37% of patients relapse within 1 yr. of remission in primary care

5. Depression - Diagnosis by DSM-IV criteria • At least five of the following symptoms (including either 1 or 2) for two weeks and • causing clinically significant distress or impairment in functioning – • Depressed mood • Loss of interest or pleasure in almost all activities • Significant weight loss or gain, or change in appetite nearly every day • Insomnia or hypersomnia • Psychomotor agitation or retardation (observable by others) • Fatigue or loss of energy • Feelings of worthlessness or excessive or inappropriate guilt • Diminished ability to think or concentrate, or indecisiveness • Recurrent thoughts of death or suicide

6. Depression - At Risk Patients • Adverse social circumstances • Drug and alcohol misuse • Physical illness • Hospitalised patients • Patients Rx musculoskeletal/CNS drugs • Postnatal women • Action: • refer cases of suspected undiagnosed depression

7. Management • Options (alone or in combination) • Psychotherapy • Drug therapy • Electro-Convulsive Therapy • Aims of treatment • Remission of symptoms to the pre-morbid state • Restoration of social and working capacity • Reduced risk of relapse and recurrence • Prevent suicide

8. Choice of Antidepressant “There are no clinically significant differences in efficacy between TCAs and SSRIs.” Geddes JR, Freemantle N et al SSRIs versus other antidepressants for depressive disorder The Cochrane Library , Issue No4, 2000 Oxford: update Software (Cochrane review)

9. Factors Influencing Choice • Prominent features of depression • Co-existing disease states • Interacting drugs • Previous response to therapy • Individual tolerability to side effects • Ability to comply – one daily dosing may be simpler • Age of patient • Risk of overdose • Pregnancy & breast feeding • - Generally SSRI 1st line but not indicated in mild depression

10. Mechanisms Pre-synaptic Receptors: Control the release of neurotransmitter Drug Post-synaptic Receptors Transmission

11. Tricyclic Antidepressants (TCAs) • All act on Serotonin and NA but in different proportions • Also hit muscarinic, 1 receptors and histamine receptors – responsible for side effects • Some more toxic in overdose than others • Reserved for 3rd – 4th line these days

12. Selective Serotonin Re-uptake Inhibitors (SSRIs) • Serotonergic side effects • GI – Nausea, vomiting, dyspepsia • Central – dizziness, agitation, insomnia, headache • Others – Dry mouth, sexual dysfunction, bleeding disorders, anorexia or weight loss. • Usually 1st line agents • Useful for patients with physical problems as have good side effect profile

13. Monoamine Oxidase Inhibitors (MAOIs) • Boost available monoamines by inhibiting breakdown by monoamine oxidase enzyme (centrally & peripherally) Irriversible inhibitors -Phenelzine, tranylcypromine, Isocarboxazid • Consumption of tyramine rich foods or sympathomimetic agents results in hypertensive crisis –dietary restrictions apply • Must not be prescribed with other antidepressants – washout must be observed • Risks in elective surgery Reserved as 4th-5th line but useful in phobic patients or those with atypical hypochondriacal or hysterical features Reversible inhibitors –Moclobemide - Dietary restrictions less necessary

14. Venlafaxine & Duloxetine(SNRIs) • Boost serotonin & NA levels by reuptake mechanism • New monitoring guidelines for venlafaxine – baseline ECG and blood pressure. Not to be used if cardiac risk factors present. ECG & BP monitoring on therapy. • Some evidence to support high doses (225mg) in treatment resistant depression. Still used in secondary care. Associated with raised BP. • Side effects include nausea, insomnia, agitation, restlessness, ECG changes, hypertension, withdrawal effects (even with missed doses) • Duloxetine does not have the same monitoring requirements but not much experience with it yet

15. Mirtazapine (NaSSA) • Noradrenergic and specific serotonergic antidepressant • presynaptic 2 antagonist – increases NA and serotonin levels centrally but post synaptically blocks 5HT2 and 5HT3 subtypes so there is a specific action on 5HT1. Less sleep disturbance and less sexual dysfunction • Also histaminergic – responsible for sedation and weight gain • Practically no anticholinergic effects and no cardiovascular effects • Rarely blood dyscrasias

16. Reboxetine (NARI) • Noradrenaline reuptake inhibitor (weak effect on 5HT) • Side effects – insomnia, sweating, dizziness, urinary hesitancy • Can be considered 2nd or 3rd line therapy as favourable side effect profile

17. General Risks of Antidepressant • All antidepressants can cause hyponatraemia (CSM warning) • All lower seizure threshold to some extent. • All can cause sweating • All can cause “switching” in bipolar patients • Discontinuation reactions can occur with all antidepressants, but are more common in short half life agents regardless of class. • Combinations of antidepressants are potentially risky and should be used only under specialist supervision. • Switching drugs should be carried out with care.

18. The Role of the Pharmacist • Reduce stigma by using a responsive pro-active approach • Be responsive to possibility of undiagnosed depression • Provide information about antidepressants • Promote concordance • Monitor and provide support to patient & carers • Identify adverse effects and interactions (including non-prescribed medication) • Discourage self diagnosis and treatment • Support people at risk of suicide

19. Initial Prescription for Antidepressant • Reduce stigma - reassure patient depression is a common illness and most patients recover • Emphasise lag period – side effects often present before benefit, encourage to persevere. • Discuss discontinuation reactions but reassure that medication is not addictive. Do not stop abruptly. • For SSRIs ensure GP has discussed side effects – patient should report any increase in suicidal thoughts or increase in agitation or anxiety (may be indicative of akathisia). Discuss common side effects of any antidepressant. • Ensure patient aware of expected duration of treatment. • Result : Improved concordance, reduced potential for relapse.

20. Lack of Response/Switching • Ensure adequate trial. Where some response a dose increase may be considered. • Usually switch to a different class is indicated, but can switch within a class in certain circumstances • Switching guidelines – • In theory it is better to stop and washout one drug before starting another (must do this with MAOIs) • In practical terms this is rarely possible if patient is ill. • Potential problems with cross tapering include – antidepressant discontinuation effects, interactions between the 2 drugs e.g. some SSRIs increase TCA levels, serotonin syndrome (potentially life threatening), cholinergic effects. • If in doubt – seek specialist advice!

21. Stopping antidepressants • If stopped abruptly discontinuation symptoms may include – • Headaches, restlessness GI symptoms, flu like symptoms, abdominal cramps, sleep disturbance, anxiety, agitation “electric shock” sensations (particularly with SSRIs) • Common with short half life drugs, rare with fluoxetine To avoid problems – • After < 8 weeks treatment withdraw over 1-2 weeks • After 6-8 months treatment taper over 6-8 weeks • After long term maintenance, reduce dose by 25% every 4-6 weeks.

22. How to Identify and Meet the Pharmaceutical Care Needs • Education checklist for first presentation or changes in dose or medication • Pharmaceutical care needs assessment for depression to identify gaps in patient knowledge, effectiveness, safety and compliance • Implement as part of your own CPD or local project.