Antipsychotic Medication

Transcription

1 Antipsychotic Medication Mary Knutson, RN Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 1

2 Clinical Uses of Antipsychotics Short-term: in severe depression and in substance-induced psychosis Treatment of aggressiveness and behavioral problems with pervasive developmental disorders Useful in elderly patients with dementia; delirium with agitation and psychosis Decrease vocal tics in Tourette syndrome Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 2

3 Phenothiazines Typical Antipsychotics Chlorpromazine (Thorazine), thioridazine (Mellaril), mesoridazine (Serentil), perphenazine (Trilafon), trifluoperazine (Stelazine), fluphenazine (Prolixin) Thiothixene (Navane) Butyrophenone: haloperidol (Haldol) Dibenzoxazepine: loxapine (Loxitane) Dihydroindolone: molindone (Moban) Diphenylbutylpiperidine: pimozide (Orap) Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 3

4 Atypical Antipsychotics Aripiprazole (Abilify) Clozapine (Clozaril) Paliperidone (Invega) Risperidone (Risperdal, Consta, M-Tabs) Olanzapine (Zyprexa, Zydis) Quetiapine (Seroquel) Ziprasidone (Geodon) Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 4

5 Target Symptoms for Antipsychotics Positive symptoms: excess or distortion of normal function Psychotic disorders of thinking: delusions or hallucinations Disorganization of speech and behavior: thought disorder (incoherence, derailment, illogicality), bizarre behavior Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 5

6 Target Symptoms for Antipsychotics Mood symptoms Cognitive impairment Difficulty with socialization Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 6

7 Target Symptoms for Atypical Antipsychotics Negative symptoms: decrease or loss of normal function Flattened affect Alogia (restricted thought and speech) Avolition/apathy Anhedonia/asociality Attentional impairment Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 7

8 Treatment Plan Initial nursing treatment plan should address target symptoms; selection of drug, dose, response, observed side effects and their treatment; patient safety, education, reassurance Nurse-patient relationship forms basis for ongoing therapeutic alliance Nonpharmacological treatment of residual symptoms of psychosis more successful when patient s behavior, mood, and thought processes begin to improve with medications Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 8

9 Drug Action of Atypical Antipsychotics Block at dopamine 2 (D 2 ) and serotonin 2 (5-HT 2 ) postsynaptic receptors; thus they are DA and 5- HT antagonists Aripiprazole: new generation of atypical antipsychotics, a dopamine-serotonin stabilizer; partial agonist (enhancer) at D 2 and 5-HT 1A receptors and has antagonistic (blocking) activity at 5-HT 2A receptors Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 9

10 Advantages of Atypical Antipsychotics Improve positive symptoms of schizophrenia, but unlike typical drugs, they also improve negative symptoms Atypical drugs reported to treat mood symptoms, hostility, violence, suicidal behavior, difficulty with socialization, cognitive impairment seen in schizophrenia Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 10

11 Disadvantages of Atypical Drugs Can result in metabolic syndrome Problems with this syndrome: weight gain, diabetes, and dyslipidemia, often resulting in cardiovascular disease Higher cost compared with typical antipsychotics However, cost/benefit analyses show cost outweighed by improved effectiveness and quality of life of patients taking these drugs Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 11

12 Side Effects of Atypical Antipsychotics Risperidone: elevate serum prolactin levels; may cause extrapyramidal symptoms (EPS) at higher doses Weight gain and metabolic disturbances; side effects (except ziprasidone and aripiprazole); olanzapine and clozapine highest likelihood of causing problems Sedation commonly observed in patients taking quetiapine, olanzapine, or clozapine Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 12

13 Side Effects Because ziprasidone associated with mild/moderate prolonged Q-T interval, may need monitoring of ECGs and cardiac functioning Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 13

14 Side Effects Clozapine often reserved for patients with treatment-resistant illness because of side effects: agranulocytosis, seizures, myocarditis Prescribers must follow treatment protocol, entering patients in national registry, monitoring WBC count every 1-2 weeks, and writing prescriptions for maximum of 2 weeks Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 14

15 Drug Action of Typical Antipsychotics Dopamine (DA) antagonists: they block postsynaptic D 2 receptors in several DA tracts in brain; decrease in positive symptoms of schizophrenia and EPS Have synaptic effects in other transmitter systems; broad side effect profile Selection of drug determined by extent, type, severity of side effects Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 15

16 Drug Action A low-potency drug (chlorpromazine) reduces risk of EPS; high-potency drug (haloperidol) minimizes sedation, postural hypotension, anticholinergic effects Have not been particularly effective in treating cognitive impairment and mood symptoms, the other dimensions of schizophrenia Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 16

17 Side Effects of Antipsychotics Discomfort to life-threatening emergency EPS Acute dystonic reactions Akathisia Parkinson syndrome Neuroleptic malignant syndrome (NMS) Seizures Agranulocytosis Photosensitivity, anticholinergic effects, or metabolic syndrome Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 17

18 Extrapyramidal Symptoms EPS and tardive dyskinesia: side effects of typical antipsychotics Result in patient nonadherence with drug EPS common and often painful, disabling Also stigmatizing but usually can be prevented or minimized and effectively treated, except for tardive dyskinesia, which may remain Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 18

19 Extrapyramidal Side Effects Mimic extrapyramidal disease by causing: Involuntary movement Changes in muscle tone Abnormal posture May resemble Parkinson disease Caused by drugs that block dopamine receptor sites Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 19

20 Acute Dystonic Reactions Sudden spasms of major muscle groups that are frightening and painful They may need treatment with medication Occur mostly with high-potency drugs or with abrupt withdrawal Oculogyric crisis is when eyes stay in an up or sideways position for minutes or several hours Torticolis is when head is inclined to one side involuntarily because of muscle contractions Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 20

21 Akathisia Inability to remain still Pacing Inner restlessness Leg aches relieved by movement Need to rule out anxiety or agitation, then medicate patient Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 21

22 Parkinson Syndrome Akinesia: abnormal state of hypoactivity or muscle paralysis Cogwheel rigidity: abnormal rigor in muscle tissue, including jerky movements when muscle passively stretched Fine tremor: quick, rhythmic, quivering movements that sometimes disappear during purposeful movements Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 22

23 Tardive Dyskinesia (TD) Can occur after use (usually long use) of conventional antipsychotics Involuntary movements: tongue protrusion, lip smacking, chewing, blinking, grimacing, choreiform movements of limbs and trunk, foot tapping Use preventive measures, and assess often Consider changing to atypical antipsychotic because there is no treatment for TD Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 23

24 Treatment Principles Tolerance to side effects usually develops by third month Decrease dose of drug May add a drug to treat EPS, then taper after 3 months on antipsychotic Use a drug with lower EPS profile Give patient education, support Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 24

25 Drug Strategies to Treat EPS Administer one of these drugs: Anticholinergics: benztropine (Cogentin), trihexyphenidyl (Artane), biperiden (Akineton), procyclidine (Kemadrin) Antihistamine: diphenhydramine (Benadryl) Dopamine agonist: amantadine (Symmetrel) Benzodiazepines: diazepam (Valium), lorazepam (Ativan), clonazepam (Klonopin) Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 25

26 Neuroleptic Malignant Syndrome Rare but potentially fatal (14%-30% mortality) side effect of antipsychotic drugs Fever, tachycardia, sweating, muscle rigidity, tremor, incontinence, stupor Treatment: stop triggering drug, initiate supportive care Important reason for nurse to assess carefully for drug side effects Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 26

27 Other Side Effects of Anticholinergic effects Antipsychotics Constipation, dry mouth, blurred vision, orthostatic hypotension, tachycardia, urinary retention, nasal congestion Metabolic syndrome Weight gain, diabetes, and dyslipidemia, often resulting in cardiovascular disease Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 27

28 General Pharmacological Principles Dosage requirements for individual patients vary considerably, must be adjusted as target symptoms change and side effects monitored Some patients begin to respond to sedating effects of typical drugs in 2-3 days, some take as long as 2 weeks Full benefits may take 4 or more weeks Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 28

29 Drug Effects Atypical drugs may begin to work in 1 week but take several months to reach maximum efficacy Thus patient, family, and clinician must not increase dose prematurely because this strategy usually increases side effects and not effectiveness Brief course of benzodiazepine may help patient maintain control during this time Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 29

30 Changing Drug Therapy Patient unresponsive to antipsychotic trial often responds to another antipsychotic in a second trial Clozapine is usually considered only after second trial failure (when patient is considered treatment resistant) When switching from one antipsychotic to another, gradually decrease one drug while gradually increasing new drug (cross-titration) over 2-4 days Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 30

31 Preparations of Antipsychotics Several typical (haloperidol) and atypical (ziprasidone) antipsychotics have short-acting injectable preparation, can be administered IM in acutely agitated patients Often provides relief for acutely ill patient while oral formulations begin to work or until acute crisis resolved Some in oral disintegrating tablet form Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 31

32 Maintenance Treatment May include injectable preparations if patient unable to adhere adequately to daily dosing regimen Long-acting (haloperidol decanoate, fluphenazine decanoate, Risperdal Consta) typical and atypical drugs available Test ability to tolerate first by administering oral form for several days, then administering injection that may last for many weeks Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 32

33 Antipsychotics Taper slowly over days to weeks to avoid dyskinetic reactions and side effects Do not cause chemical dependency or tolerance to antipsychotic effects Low abuse potential; safe in overdose Effects on fetus inconclusive, but must consider what is best for pregnant mother Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 33

34 Role of Nurse Minimize patient s fears Decrease any sense of stigmatization Enhance adherence to drug treatment Provide effective patient education Support patient, family Manage intensive, comprehensive medication regimen Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 34

35 References Stuart, G. (2009). Principles and practices of Psychiatric Nursing (9 th ed.) St. Louis: Mosby Mosby items and derived items 2009 by Mosby, Inc., an affiliate of Elsevier Inc. 35