Acting Injectable Antipsychotics

For patients with chronic psychotic symptoms who do not comply with a daily medication regimen, a long-acting depot preparation should be considered after stabilization with oral medication. Fluphenazine, haloperidol, and risperidone are the only long-acting injectable antipsychotic medications currently available in the United States. 

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Depot or long-acting antipsychotics are recommended for patients who are unreliable in taking oral medication on a daily basis, and thus are not usually used as first-line therapy. Before a long-acting antipsychotic is initiated, it should be determined whether the patient s medication nonadherence is because of side effects. If so, an alternative medication with a more favorable side-effect profile should be considered before a long-acting injectable antipsychotic. 

Maintenance with injections of the decanoate ester of fluphenazine or haloperidol every 2—4 weeks, or with long-acting risperidone microspheres every 2—3 weeks, can be very effective. However, an expectation of superiority of long-acting injected antipsychotics is not well supported by available studies, most of which involve randomization of patients who already are largely cooperative with long-term oral treatment. 

Depot antipsychotics (e.g., haloperidol decanoate, fluphenazine decanoate, and risperidone long-acting injection) can be used for maintenance therapy of bipolar disorder with noncompliance or treatment resistance. 

If partial or poor adherence is an issue, a long-acting or depot injectable antipsychotic should be considered (e.g., risperidone microspheres, halo-peridol decanoate, fluphenazine decanoate). 

Fluphenazine (Prolixin). Fluphenazine is another high potency antipsychotic. It is widely used to treat psychosis and comes in oral, injectable, and long-acting injectable (depot) forms. Its side effect profile is typical of the other high potency antipsychotics. 

Bhanji NH, Chouinard G, Margolese HC. A review of compliance, depot intramuscular antipsychotics and the new long-acting injectable atypical antipsychotic risperidone in schizophrenia. Eur Neuropsychopharma-col. 2004 14 87-92. 

Turner M, Eerdekens E, Jacko M, Eerdekens M. Long-acting injectable risperidone safety and efficacy in stable patients switched from conventional depot antipsychotics. Int Clin Psychopharmacol 2004 19 241-9. 

Medication may be seen by the patient as intrusive and controlling or, alternatively, as comforting—a transitional, object-like extension of the therapist. Patients will be prone to interpret the medication in psychotic ways, especially when they are more symptomatic (and more in need of medication). When compliance remains a significant problem, consideration may be given to using one of the long-acting injectable forms of the antipsychotics (haloperidol decanoate or fluphenazine de-canoate). 

Kane JM, Eerdekens M, Lindenmayer JP, et al. Long-acting injectable risperidone Efficacy and safety of the first long-acting atypical antipsychotic. Am J Psychiatry 2003 160 1125-1132. 

Alphs L, Bossie CA, Sliwa JK, Fu D-J, Ma Y-W, Hulihan J. Paliperidone pahnitate and risperidone long-acting injectable in subjects with schizophrenia recently treated with oral risperidone or other oral antipsychotics. Neuropsychiatr EHs Treat 2013 9 341-50. 

Depot injection A long-acting formulation of an antipsychotic drug given by occasional (often monthly) intramuscular injection. 

When an antipsychotic is needed, we prefer using one of the newer atypical agents olanzapine, ziprasidone, risperidone, quetiapine, or aripiprazole. Each of these medications reliably reduces agitation and is well tolerated. In particular, they decrease the potential for acute dystonic reactions and tardive dyskinesia caused by the typical antipsychotics. Both ziprasidone and olanzapine are now available in an injectable form that is very rapidly acting and effective in this setting. 

Intended for use in chronic psychotic patients who require prolonged parenteral antipsychotic therapy. These patients should be previously stabilized on antipsychotic medication, and should have been treated with, and well tolerated on short-acting haloperidol in order to exclude the possibility of an unexpected adverse sensitivity to haloperidol. Close clinical supervision is required during the initial period of dose adjustment in order to minimize the risk of overdosage or reappearance of psychotic symptoms before the next injection. During dose adjustment or episodes of exacerbation... 

Haloperidol is used as an antipsychotic and occasionally for control of acute agitation in the intensive care unit. It is can also be useful in the treatment of phencyclidine abuse. It produces a cataleptic state with little drowsiness and has minimal effects on blood pressure and respiration. It is a long-acting drug with a half-life of about 18 hours. It is available in oral and injectable preparations. In large doses extrapyramidal side effects may occur. 

Oral antipsychotic medication should be given with the first injection of long-acting risperidone and continued for 3 weeks, then discontinued... 

For missed long-acting risperidone injections 2 or more weeks late (i.e., 28 or more days following last injection), may need to provide antipsychotic coverage with oral administration for 3 weeks while reinitiating injections... 

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