Polypharmacy in Psychiatry
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Transcript of Polypharmacy in Psychiatry
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Poly-pharmacy in Psychiatry
Introduction
• Historically, Poly-pharmacy for psychiatric disorders has been frowned upon.
• Seen as evidence of poor clinical judgment.
• Seen as either overmedicated or improperly diagnosed.
Definition
• It can be defined as-– Use of two or more medications to treat
the same condition, – Use of two or more drugs of the same
chemical class,– Use of two or more drugs with the same
or similar pharmacologic actions to treat different conditions.
Ref- Kingsbury SJ, Donna Yi, Simpson GM. Rational and Irrational Polypharmacy. PSYCHIATRIC SERVICES ♦ August 2001 Vol. 52 No. 8
What is the impact ???
• Kukreja et al (2013)- reported prevalence rates of poly-pharmacy in psychiatry to vary between 13-90%.
• Rittmannsberger et al (2002)- mono-therapy in psychiatry patients– <1980 in 48%, – 1981-1990 in 31% &– 1991-2000 in 20%.
Socio-Demographic factors
• De las Cuevas & Sanz ( 2004)- – Adult men > women,– Antidepressants were the most common
co-prescribed followed by ADHD medications, antipsychotics.
– More common with ICD-10 diagnosis of Schizophrenia, Schizotypal & Delusional disorders.
Impact in Geriatric population…
• In geriatric group it is often a rule rather than exception !!!...
• In adults >65yrs-– Over 90%- atleast 1 medication/ week.– Over 57%- >5 medications/ week.– Over 12%- >9 medications/ week.
• Cohort study comparing medicine use b/n 98-03→ >5 medications ↑ from 54% to 67%.
• Beers criteria, provides a list of medications that should be avoided in geriatric patients.
Ref: Bryan D et al. polypharmacy and geriatric patient. Clin geratric med 23 (2007) 371- 390.
Geriatric poly-pharmacy
• Adverse drug events (ADEs)- approx. 10% in emergency department.
• Risk factors for ADEs- poly-pharmacy, comorbid conditions, prior ADEs, dementia.
• Drugs implicated in ADEs- Anti-cholinergics, BZDs, TCAs.
• Common ADEs- electrolyte, renal, GI, hemorrhagic & endocrine abnormalities.
• Drug-drug interactions ↑ with ↑ in medications.• Drugs with narrow therapeutic index are frequently
involved like digoxin, CCBs, TCAs, warfarin etc..,
Geriatric pharmacokinetics
• ↑ Sensitivity to drug effects→ due to alterations in renal, hepatic, endocrine, cardiovascular, neurologic functions.
• Exaggerated responses to centrally acting drugs like barbiturates, opioids, TCAs, BZDs, central α agonists.
• ↓ Baroreceptor responsiveness and sensitivity leading to ↑ risk of hypotension.
• Alterations in absorption and distribution, fat to lean body mass ratio, plasma albumin levels contribute to variations.
• Changes in drug metabolism in turn lead to exaggerated responses.
Types of poly-pharmacy
1. Same-Class Poly-pharmacy- Use of more than one medication from the same class ( 2 SSRI’s).
2. Multi-Class Poly-pharmacy - Use of more than one medication from different classes for the same symptom cluster (Val + Olan).
3. Adjunctive Poly-pharmacy- Use of one medication to treat the side effects of another medication from a different class (Risp + THP).
4. Augmentation Poly-pharmacy- – Use of one medication at a lower dose along with another
medication from a different class in full therapeutic dose for the same symptom cluster (Risp + low dose Hal),
– Addition of a medication that would not be used alone for the same symptom cluster (Li + T3).
Ref- Medical Directors Council and State Medicaid Directors. Alexandria, Virginia: 2001.NASMH Program Directors: Technical Report on Psychiatric Polypharmacy.
Is Poly-pharmacy required ???
• Stahl's Essential Psycho-pharmacology & Doran's The Practitioner's Guide, promote synergistic drug combinations.
• Majority of psychiatric patients benefit from synergistic drugs, they also are essential for achieving and maintaining recovery.
• In clinical practice it is very difficult to achieve a full remission or recovery with mono-therapy.
• So poly-pharmacy of mental health medications should be rather a rule than an exception.
Ref: Jakovljević M. How to increase treatment effectiveness & efficacy in psychiatry: Creative psychopharmacotherapy Part 1. Psychiatria Danubina, 2013; Vol. 25, No. 3, pp 269-273
Reasons for Poly-pharmacy…
1. Treat two patho-physiologically distinct but co-morbid illnesses in the same patient (Parkinson’s dis +Psychosis).
2. To treat an adverse effect produced by the primary drug (Risp + THP).
3. To provide acute amelioration while awaiting the delayed effect of another medication (AD + BZD).
4. To treat intervening phases of an illness ( In treatment of Post psychotic depression).
5. To boost/ augment the efficacy of primary treatment (AD + L methyl folate, AP + AD in –ve schiz).
Ref: Preskorn SH, Lacey RL. Polypharmacy: when is it rational? J Psychiatr Pract. 2007;13:97–105.
What Poly-pharmacy is not…
• Irrational poly-pharmacy-1. Clinician’s fear about poor and unstable
state of patient.
2. Sloppy diagnosis.
3. Stuck in cross-titration of drugs.
4. Blind adherence to specifications in guidelines.
5. Inadequate knowledge of receptor pharmacology or a lack of attention to it.
Ref- Kingsbury SJ, Donna Yi, Simpson GM. Rational and Irrational Polypharmacy. PSYCHIATRIC SERVICES ♦ August 2001 Vol. 52 No. 8
Creative/ Rational Poly-pharmacy
• Ghaemi et al (2001)- It is the skillful & rational combination of mental health drugs.
• Combining drugs with synergistic therapeutic effect between the drugs.
• Joseph et al (1997)- – Multiple drugs with each for a specific target
symptom, – Each evaluated individually for efficacy and side
effects and adjusted optimally, – Elimination of each one that is no longer
necessary.
Ref: Jakovljević M. How to increase treatment effectiveness & efficacy in psychiatry: Creative psychopharmacotherapy Part 1. Psychiatria Danubina, 2013; Vol. 25, No. 3, pp 269-273
Poly-pharmacy in Depression
Poly-pharmacy in Depression
• AD + Li-– Li is the best-studied augmenter to AD.– Addition of Li to a TCA resulted in clinical
improvement <72 hrs in pts who had failed to respond to a TCA alone.
– Addition of Li also appears to prevent relapses in unipolar depression more effectively than an AD alone.
– Pts are likely to improve with Li, if they exhibit significant psychomotor retardation, anorexia, weight loss, and low serum cortisol levels.
Poly-pharmacy in Depression
• AD + Thyroid supplement– As effective as Li augmentation.– Studies have suggested that T3 at 25-50 mcg/d,
when added to various SSRIs, potentiate their effects.
– In STAR*D trial, pts who had failed with mono-therapy & when augmented with T3, 25% had attained remission.
– Pt likely to respond include females, h/o thyroid abnormalities, females >50 yrs (perhaps more susceptibility to hypothyroidism).
Poly-pharmacy in Depression
• AD + Stimulant like agents– Include Amphetamines, Pramipexole,
Bupropion, Modafinil.– Amphetamines to target fatigue, hypersomnia
and cognitive difficulties.– Pramipexole + SSRIs has role in treatment
resistant depression at doses 1 mg/d.– Modafinil to target fatigue and hypersomnia.– In STAR*D trial, Bupropion had a remission rate
of 30% in patients who had failed in mono-therapy.
Poly-pharmacy in Depression
• AD + AP– Augmenters & Adjuncts in Unipolar & Bipolar
depression.– 5-HT2 antagonism of AP has long been thought
to produce antidepressant properties.– They clearly help in symptoms like sleep,
appetite & agitation.– Olanzapine is among the most studied for the
augmentation in resistant depression. – 10-20 mg/day of Olan + Flx effective in
treatment of resistant depression.
Poly-pharmacy in Depression
• AD + AD– STAR*D trail, found 30% remission with
addition of Buspirone/ Bupropion to Citalopram.
– STAR*D trial, combination of Venlafaxine & Mirtazapine showed improvement in depressive symptoms.
– H1 blocking of mirtazapine may make it a useful augmentor to SSRIs in insomnia.
Poly-pharmacy in Schizophrenia
Poly-pharmacy in Schizophrenia
• AP + AD– To alleviate affective symptoms, like
inter-current major depressive episode.– Studies confirmed efficacy of citalopram
& duloxetine in treatment of depression in schizophrenia.
– SSRIs have showed beneficial impact on negative symptoms.
– Bupropion (NDRI) successful in smoking cessation in schizophrenia.
Poly-pharmacy in Schizophrenia
• AP + Li/ Anticonvulsants– Most common add on strategy.– Valproic acid had beneficial impact on
aggression & tardive dyskinesia.– Carbamazepine proved improvement in
global psychopathology.– Topiramate showed weight loss, pro-
glutamatergic effects & affective stabilization.
– But not supported by strong evidence.
Poly-pharmacy in Schizophrenia
• AP + AP– Clozapine- Anti-suicidal effect & lower
mortality rates than other AP.– For agonistic effects-
• 5HT & Adr system- Ziprasidone.• Differential agonistic and antagonistic effects
in the D- Aripiprazole.• D receptor blockade- sulpride/ Amisulpride.
– Evidence for Risp + Clozapine supported by RCTs.
Poly-pharmacy in Schizophrenia
Anti-Psychotic combination
Study population Results
Olanzapine + Aripiprazole
Overweight, Obese ↓ Weight, BMI, TAG.
Olanzapine + Amisulpride
Partial response to Olanzapine
Improvement in symptoms.
Clozapine + Aripiprazole
On treatment with Clozapine
Improvement in glucose tolerance, ↓ LDL.
Clozapine + SGAs
Analysis of 14 double blind studies
Modest benefit.
Quetiapine/ Risperidone + Aripiprazole
Patients stabilized on Quetiapine/ Rispeidone
↓ PRL levels.
Certain combinations of Antipsychotics
Poly-pharmacy in Schizophrenia
• Amelioration of AP side effects– Akathisia- add on Mirtazapine/ switch to
better tolerated AP.– Weight gain- Reboxetine (AD)/
Metformin.– Add on Aripiprazole to Clozapine to
reduce- mean body weight, waistline, BMI, fasting total & LDL cholestrol.
Ref: Zink M, Englisch S, Lindenberg AM. Polypharmacy in schizophrenia. CurrentOpinioninPsychiatry2010,23:103–111
Poly-pharmacy in Schizophrenia
Effect on receptors
Consequences of blockade
AP with high affinity
D2 antagonism in striatal area
EPS Fluphenazine, haloperidol, risperidone
D2 antagonism in Infudibular system
Hyperprolactinemia Amisulpride, haloperidol, sulpride, riperidone, paliperidone, zotepine
H1 antagonism Weight gain, sedation Clozapine, olanzapine, quetiapine
M1 antagonism Dry mouth, constipation, cognitive impairment
Clozapine, olanzapine, quetiapine
α1 antagonism Orthostatic hypotension, tachycardia
Asenapine, chlorpromazine, clozapine, risperidone, sertindole, ziprasidone
Interactions potentially causing adverse events
Sagud M et al. antipsychotic: to combine or not to combine. Psychiatria Danubina, 2013; Vol. 25, No. 3, pp 306-310
Poly-pharmacy in Geriatric
Poly-pharmacy in Geriatric
• Anti-depressants– Sproule et al noted drug interactions of SSRIs
are secondary cytP450 induction.– SSRI + Warfarin is associated with enhanced
anticoagulation.– COPD pts on theophylline, can develop toxicity
if on Flx or Fluvoxamine.– Alzheimer’s pts on Tacrine, can develop toxicity
due to ↑ tacrine if on Fluvoxamine.– Toxicity of terfenadine, astemizole,
carbamezapine are ↑ with SSRIs.
Ref: Katona CLE. Psychotropics and drug interactions. Int J Geriatr Pscyhiatry 2001; 16: S86-90.
Poly-pharmacy in Geriatric
• Mood stabilizers– Prone for Li toxicity due to ↓ renal
capacity→ alteration in consciousness and tremors.
– Li + Verapamil→ neurotoxicity and bradycardia.
– Carbamazepine may reduce anticoagulant effects of warfarin when co-administered.
– Cimetidine, Dextropropaxyphene may cause carbamezapine toxicity.
Poly-pharmacy in Geriatric
• Anti-psychotics– Phenothiazines + Cimetidine→ enhanced
sedative effect due reduced metabolism.
– Haloperidol + Li→ ↑ Li neurotoxicity.
– SSRI + Clozapine→ ↑ Clozapine toxicity.
– Clozapine ↑ neurotoxicity of Li, BZDs (sedation, hypertension, resp arrest).
– Cigarette smoking ↑ metabolism of Clozapine & Olanzapine→ reduction in effects.
In simple terms…
• Physicians prescribing psychiatric drugs must be aware of the existence and high prevalence of poly-pharmacy.
• Poly-pharmacy suggests two or more medications are being used to treat the same/ different conditions in a patient.
• Poly-pharmacy may be necessary and justified particularly when there are co-morbidities & when mono-therapy provides insufficient improvement
• One can deal with polypharmacy with SAIL and TIDE approaches:– SAIL: Simple drug regimen, Adverse effects knowledge, clear Indication, keep List
of drug name and dosage in patient's chart.
– TIDE: Allow Time to address medication issues, understand Individual variability, avoid potential dangerous Drug-drug interactions, and Educate patients regarding treatment.
• Education, proper clinical titration aided by guidelines and protocols are effective ways to avoid irrational poly-pharmacy.
Questions???
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Department of Psychiatry