Many of the antipsychotic medications block post-synaptic D2 receptors in the central nervous system, particularly in the mesolimbic-frontal system.20 It has been reported that for an antipsychotic to be considered effective, it must exhibit a level of dopamine antagonism of at least 60 to 80% because lower levels of dopamine antagonism generally do not produce observable antipsychotic effects, and in about 60% to 70% of patients, schizophrenia may not be adequately controlled.19

Patients with schizophrenia require long-term maintenance antipsychotic treatment, so the effectiveness of antipsychotic medication is vital if they are to perform the activities of daily living and sustain an adequate quality of life.21


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Individuals with a new diagnosis of schizophrenia may appear to be more sensitive to antipsychotic medication therapies than those with a long-standing diagnosis; however, regardless of the selection, antipsychotic medications have demonstrated comparable efficacy and achievement of symptom control.21

Clinicians must be familiar with the available typical and atypical antipsychotics and their dose ranges, relative potencies, side effect profiles, and monitoring parameters (Tables 2–8).21,22 The selection of the appropriate antipsychotic medication is at the discretion of the prescribing provider, but patient preference, tolerance, and efficacy should also be considered to increase the probability of achieving optimal therapeutic results.22 


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Initiation and outcome of patients who have had antipsychotic therapy 

Patients undergoing antipsychotic treatment for schizophrenia commonly exhibit poor adherence, characterized by high rates of discontinuation and frequent changes in treatment. For these reasons, effective treatment interventions are of utmost importance.23 The administration of very high doses initially, causing “neurolepsis,” is no longer recommended because of increased side effects and lack of benefit. 

Continuous maintenance of an antipsychotic medication at the minimal effective dose may be the best approach in most cases. Typical agents are associated with greater long-term risks than atypical agents. For some patients who have had a first episode and have been symptom-free for 2 years, a trial off drugs may be attempted. Patients with a prior history should be symptom-free for 5 years before drug discontinuation is considered.24 

Treatment goals

There is generally no gold standard in the selection of antipsychotic medications for schizophrenia; the choice can be based on patient preference, tolerability, and side effect profile. The goal in treating schizophrenia is to reduce or eliminate the frequency/occurrence of symptoms, attempt to maximize quality of life and improve adaptive functioning skills, and enable recovery by assisting patients in attaining personal life goals (eg, in work, housing, and interpersonal relationships). 

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During the treatment process, the pharmacist can serve as a drug information specialist, informing patients about expected side effects, potential drug interactions, and other facts relevant to antipsychotic therapy. When the pharmacist provides this valuable information, patients can acquire a better idea of what to expect from their antipsychotic medication. 

Abimbola Farinde, PhD, PharmD, is a professor at Columbia Southern University in Orange Beach, Alabama.

References

  1. Gupta S, Kulhara P. What is schizophrenia: a neurodevelopmental or neurodegenerative disorder or a combination of both? A critical analysis. Indian J Psychiatry. 2010;52:21-27.
  2. Hahn RK, Albers LJ, Reist C. Psychiatry. Blue Jay, CA: Current Clinical Strategies Publishing; 2008.
  3. Kandil F, Pedersen A, Wehnes J, Ohrmann P. High-level, but not low-level, motion perception is impaired in patients with schizophrenia. Neuropsychology. 2013;27:60-68.
  4. Rollins A, Bond G, Lysaker P, McGrew J, Salyers M. Coping with positive and negative symptoms of schizophrenia. Am J Psychiatr Rehabil. 2010;13:208-223.
  5. Kirkpatrick B, Fenton WS, Carpenter WT Jr, Marder SR. The NIMH-MATRICS consensus statement on negative symptoms. Schizophr Bull. 2006;32:214-219.
  6. Flanagan E, Solomon L, Johnson A, Ridgway P, Strauss J, Davidson L. Considering DSM-5: the personal experience of schizophrenia in relation to the DSM-IV-TR criteria. Psychiatry. 2012;75:375-386.
  7. Schaub D, Brüne M, Jaspen E, Pajonk F, Bierhoff H, Juckel G. The illness and everyday living: close interplay of psychopathological syndromes and psychosocial functioning in chronic schizophrenia. Eur Arch Psychiatry Clin Neurosci. 2011;261:85-93.
  8. Strauss J, Bowers M, Keith S, Bleuler M. What is schizophrenia? Schizophr Bull. 1984;10:8-10.
  9. Hoffmann H, Kupper Z, Kunz B. Hopelessness and its impact on rehabilitation outcome in schizophrenia—an exploratory study. Schizophr Res. 2000;43:147-158.
  10. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Arlington, VA: American Psychiatric Publishing; 2013.
  11. Keller W, Fischer B, Carpenter J. Revisiting the diagnosis of schizophrenia: where have we been and where are we going? CNS Neurosci Ther. 2011;17:83-88.
  12. Idrees M, Khan I, Irfan M, Sarwar R. First rank symptoms in the diagnosis of schizophrenia. J Postgrad Med Inst. 2010;24:323-328.
  13. Suvisaari J, Perälä J, Saarni S, Juvonen H, Tuulio-Henriksson A, Lönnqvist J. The epidemiology and descriptive and predictive validity of DSM-IV delusional disorder and subtypes of schizophrenia. Clin Schizophr Relat Psychoses. 2009;2:289-297.
  14. Fenton WS, McGlashan TH. Natural history of schizophrenia subtypes. I. Longitudinal study of paranoid, hebephrenic, and undifferentiated schizophrenia. Arch Gen Psychiatry. 1991;48:969-977.
  15. Schatzberg AF, Cole JO, DeBattista C. Manual of Clinical Psychopharmacology. 7th ed. Washington, DC: American Psychiatric Association; 2010.
  16. Nisbet B, Dulmus C, Greyber L, Langa M. The spectrum clozaril clinic: a successful model for treatment of psychotic disorders. Best Pract Ment Health. 2010;6:69-84.
  17. Dickson RA, Dalby JT, Williams R, Warden SJ. Hospital days in clozapine-treated patients. Can J Psychiatry. 1998;43:945-948.
  18. Jafari S, Fernandez-Enright F, Huang X. Structural contributions of antipsychotic drugs to their therapeutic profiles and metabolic side effects. J Neurochem. 2012;120:371-384.
  19. Gardner K, Bostwick J. Antipsychotic treatment response in schizophrenia. Am J Health Syst Pharm. 2012;69:1872-1879.
  20. Conley RR, Kelly DL. Current status of antipsychotic treatment. Curr Drug Targets CNS Neurol Disord. 2002;1:123-128.
  21. Guo X, Fang M, Zhai J, et al. Effectiveness of maintenance treatments with atypical and typical antipsychotics in stable schizophrenia with early stage: 1-year naturalistic study. Psychopharmacology (Berl). 2011;216:475-484.
  22. College of Psychiatric and Neurologic Pharmacists. 2010-2011 BCPP examination review and recertification course. New Brunswick, NJ: Ortho-McNeil Janssen Scientific Affairs, LLC; 2010.
  23. Roussidis A, Kalkavoura C, Dimelis D, et al. Reasons and clinical outcomes of antipsychotic treatment switch in outpatients with schizophrenia in real-life clinical settings: the ETOS observational study. Ann Gen Psychiatry. 2013;12:42.
  24. Mayo Clinic Staff. Schizophrenia. Treatment. http://www.mayoclinic.org/diseases-conditions/schizophrenia/basics/treatment/con-20021077. Updated October 11, 2016. Accessed January 25, 2017.