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Antipsychotics and Mood Stabilizers: Pharmacokinetics Adverse Effects Drug Interactions. Philip G. Janicak, MD Professor of Psychiatry Rush University Medical Center. Goals. Antipsychotics Diagnostic indications Classification Relevant Pharmacokinetics Serious Adverse Effects
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Antipsychotics andMood Stabilizers:PharmacokineticsAdverse EffectsDrug Interactions Philip G. Janicak, MD Professor of Psychiatry Rush University Medical Center
Goals • Antipsychotics • Diagnostic indications • Classification • Relevant Pharmacokinetics • Serious Adverse Effects • Drug Interactions • Mood Stabilizers • Diagnostic indications • Classification • Relevant Pharmacokinetics • Serious Adverse Effects • Drug Interactions 2
Antipsychotics:Diagnostic Indications Psychiatric • Schizophrenia • Schizoaffective disorder • Mood disorders with psychosis • Delusional disorder Nonpsychiatric • Dementia/Delirium • Psychosis secondary to a non-psychiatric medical disorder • Developmental disability with psychosis and/or aggression • Tourette’s disorder • Nausea, vomiting 3
Negative symptoms: Affective flattening Alogia Avolition Anhedonia Social inattentiveness Positive symptoms: Delusions*Hallucinations*Disorganized speechCatatonia Cognitive symptoms: AttentionMemoryExecutive functions Moodsymptoms: DysphoriaSuicidalityHelplessness Impact of Schizophrenic Symptoms on Overall Functioning Occupational Social Work Interpersonal Self- care *Schneiderian First Rank Symptoms 4
Pharmacokinetics of Antipsychotics • ADME profiles • All are readily absorbed • All are metabolized by the hepatic cytochrome P450 system • prone to drug interactions • T1/2 is generally 20 hours except: • ziprasidone, quetiapine, aripiprazole • Dosing adjustment in elderly renal and/or hepatic impairment 5
Antipsychotic Agents © Janicak 6
Antipsychotic Agents (con’t) © Janicak 7
Antipsychotics:Adverse Effect Profiles *At appropriate doses; 0 = none; + = mild; ++ = moderate; +++ = substantial Adapted from Masand PS et al. Handbook of Psychiatry in Primary Care. 1998.
ADVERSE EFFECTS OF ANTIPSYCHOTICS Acute EPS Maximum Minimum HIGH POTENCY RISPERIDONE OLANZAPINE CLOZAPINE FGAs PALIPERIDONE ZIPRASIDONE (DOSE-RELATED) QUETIAPINE ARIPIPRAZOLE* • Psuedoparkinsonism • Dystonia • Akathisia • Tardive Dyskinesia *Based on clinical trial data 9
Risks Mortality rate CVA in 4% vs 2% Risks may be higher for all APs Recommendations Avoid in those with vascular dementia Avoid with TIA, hypertension, Afib Use low doses Monitor for hypotension, sedation, EPS Dementia Patients 10
Weight Gain: Overview • General population • Increased morbidity and mortality • Stigmatization • Major mental disorders • This adverse effect is more common with some recent antipsychotics • Recognized problem since chlorpromazine • Polypharmacy may contribute • Divalproex sodium • Lithium • Antidepressants • Antipsychotics © Janicak 11
The Metabolic Syndrome • Insulin resistance • Hyperinsulinemia • Decreased beta cell function • Postprandial hyperglycemia 12
SGAs and Metabolic Abnormalities Risk for Worsening Drug Weight Gain Diabetes Lipid Profile Clozapine +++ + + Olanzapine +++ + + Risperidone ++ D D Quetiapine ++ D D Aripiprazole* +/- - - Ziprasidone* +/- - - + = increase effect; - = no effect; D = discrepant results. *Newer drugs with limited long-term data. Diabetes Care. 2004. 13
Baseline Monitoring • History (personal or family) of obesity, diabetes, dyslipidemia, hypertension, CVD • BMI • Waist circumference • Blood pressure • Fasting lipid profile • Fasting plasma glucose 14
Anticholinergic Effects Most common with: • Clozapine • Olanzapine • Quetiapine • Low-potency FGAs © Janicak 15
Hematological • Clozapine-induced agranulocytosis • Management Stop agent Reverse isolation; supportive measures GSCF (filgastrim) • Rechallenging strategies © Janicak 16
Cardiovascular • Related to both alpha1 adrenergic and muscarinic effects • Hypotension • Tachycardia • Myocarditis • Arrhythmogenic potential possible with all antipsychotics 17
Rarely Torsade de pointes arrhythmia (syncope) Rarely Ventricular fibrillation (sudden death) Potential Consequences of QTc Interval Prolongation QTc prolongation Royal College of Psychiatrists. 1997. 18
Time between onset of depolarization and repolarization Affected by diet, alcohol intake, time of day, heart rate Usually corrected for heart rate = QTc QT interval 19
Antipsychotics:Drug Interactions • Pharmacodynamic • Anticholinergic • Hypotension • Pharmacokinetic • P450 inhibition (quinidine) • P450 induction (carbamazepine) 20
Mania Euphoria Grandiosity Pressured speech Impulsivity Excessive libido Recklessness Diminished need for sleep Depression Depression Anxiety Irritability Hostility Violence or suicide Bipolar Disorder:Symptom Domains Manic, depressed or mixed Episode • Cognition • Racing thoughts • Distractability • Poor insight • Disorganization • Inattentiveness • Confusion • Psychosis • Delusions • Hallucinations • Sensory hyperactivity 21
Mood Disorders:Therapeutic Options Lithium* (A, M) First generation antipsychotics Second generation antipsychotics Clozapine Olanzapine* (A, M) Risperidone* (A) Quetiapine* (A) Ziprasidone* (A) Aripiprazole* (A) Anticonvulsants Valproate* (A) Lamotrigine* (M) Carbamazepine (A) Oxcarbazepine* Topiramate Gabapentin • Pharmacological/Somatic • Antidepressants; OLZ/FLU* (D) • Quetiapine* (D) • Electroconvulsive therapy • Possibly: • Bright light therapy • Transcranial magnetic stimulation • Vagal nerve stimulation • Sleep deprivation Psychotherapy Cognitive behavioral therapy Marital/family counseling Interpersonal therapy Group therapy * FDA approved © Janicak 22
Narrow therapeutic index Slow onset of action Numerous adverse effects BIPOLAR DISORDER LITHIUM DISADVANTAGES © Janicak 24
Factors Affecting Lithium Cp • Impaired Renal Function • Pregnancy • Sodium balance • Medications • Diuretics → Na depletion → Li reabsorption • Caffeine ↓ lithium levels • ACE Inhibitors → ↓ GFR → increase Li concentration 25
Lithium: Adverse Effects Neurological Cognitive; tremors 26
BIPOLAR DISORDER Anticonvulsants for Mood Disorders • Valproate (VPA) • Lamotrigine (LTG) • Carbamazepine (CBZ) • Oxcarbazepine • Gabapentin (GBN) • Topiramate (TOP) • Others © Janicak 27
Adverse effects Weight gain Tremors Hyperammonemia PCOS (?) BIPOLAR DISORDER VALPROATE DISADVANTAGES • Pancreatitis • Hepatotoxicity • Teratogenicity © Janicak 28
Valproic Acid Pharmacokinetics • Usually inhibits hepatic metabolism • Occasionally induces hepatic metabolism 29
CBZ Pharmacokinetics • Oxidation to CBZ-10,11-epoxide • Potent enzyme inducer • antidepressants, anticonvulsants, antipsychotics • Autoinduction • serum level should stabilize within 4 weeks 30
Carbamazepine Metabolism Carbamazepine oxidation → Toxicity 10,11 epoxide metabolite Valproic acid X Further metabolism 31
Slow titration to avoid rash Adverse effects Serious rashes SJS TEN BIPOLAR DISORDER LAMOTRIGINE DISADVANTAGES © Janicak 32
Goals • Antipsychotics • Diagnostic indications • Classification • Relevant Pharmacokinetics • Serious Adverse Effects • Drug Interactions • Mood Stabilizers • Diagnostic indications • Classification • Relevant Pharmacokinetics • Serious Adverse Effects • Drug Interactions 33