Haloperidol depot

Chiu et al, 1992 Lin Finder, 1983 Lin et al, 1988b Potkin et al, 1984 Lin etal., 1989 Ruiz et al, 1996 Jann et al, 1989 Jann etal, 1992 Zhang-Wong etal., 1998). The majority of these studies were carried out with haloperidol. A number of studies examined differences between Caucasians and Hispanics, and African Americans and Caucasians (Midha et al., 1988b Midha etal, 1988a Ruiz et al., 1996). In general these studies provided mixed results. Another noteworthy feature of the research literature is that there appear to be no studies that have considered ethnic differences in pharmacokinetics and response for the depot antipsychotics. This may be an artifact of the low levels of depot prescribing found in the US, China, and Japan. 

Across the sites, an average of 15% of inpatients received depot antipsychotic drugs (Sim etal, 2004b). This was most common in Singapore (75%) followed by Taiwan (20%), Japan and China (6%). The depot antipsychotic drugs used were fluphenazine decanoate, flupenthixol decanoate, zuclopenthixol decanoate, haloperidol decanoate, pipothiazine palmitate, and fluphenazine enanthate. 

Intramuscular (IM) Into skeletal muscle. This route is used to deliver depot antipsychotic drugs like fluphenazine and haloperidol decanoate, which are used in the treatment of schizophrenia. 

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. 

Like fluphenazine, haloperidol is available in oral, injectable, and depot forms. In schizophrenia, haloperidol is begun at doses of 5 mg daily and increased as needed. Lower doses are used for most other indications. The depot form of haloperidol is initiated by administration of a 50mg test dose. Depot haloperidol is given monthly at about 20 times the daily dose of the oral form. The maximum depot dose is 200 mg per month. Dose dumping does not seem to be a problem with depot haloperidol. 

For patients in whom treatment noncompliance is a recurring problem, the snccess of maintenance therapy can greatly be enhanced by administering a depot formnlation of the antipsychotic. Depot formulations are currently available for haloperidol (which must be administered once every 4 weeks) and risperidone or fluphenazine (each of which must be administered once every 2 weeks). 

When esterified with a fatty acid, both fluphenazine and haloperidol can be applied intramuscularly as depot preparations. 

Among the difficulties in pharmacological treatment is the frequent non-compliance. The biggest determinant of compliance is the quality of a patient s relationship with his doctor. But a further way to handle the issue has involved the development of long acting products (depot neuroleptics), even though their effectiveness in the absolute or compared to oral preparations has not been adequately explored. The most commonly used depot agents are fluphenazine and haloperidol decanoate (see David et al., 2004). 

Quraishi S, David A. Depot haloperidol decanoate for schizophrenia. Cochrane Database Syst Rev 1999. Issue 4. 

A high risk of relapse is inherent to schizophrenic psychoses. A relapse is often triggered by emotional stress. It is very important to prevent a relapse by either maintaining low-dose oral medication or by switching to a depot antipsychotic. In some cases, this cannot be avoided. Especially when compliance is a problem, a depot medication may help to keep the patient free of psychotic symptoms. Frequently used depot antipsy-chotics are haloperidol-decanoate, fluphenazine-decanoate, and fluspirilene, which are given in relatively low dosages (see Table 41.4). In EOS, relapse prevention is more important than in adulthood, as the majority of patients have not yet finished school or started a professional career. 

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. 

Ereshefsky L, Toney G, Saklad SR, et al A loading-dose strategy for converting from oral to depot haloperidol. Hosp Community Psychiatry 44 1155-1161, 1993... 

The intramuscular administration of antipsychotics acting for weeks prevents this independent action and improves compliance on the other hand, only highly potent antipsychotics such as fluphenazine, flupenthixol and haloperidol are suitable for depot administration and it is precisely these medicines that lead more frequently to EPS and dysphoric mood (van Putten et al, 1984). 

Clinically, haloperidol decanoate has been administered to hundreds of chronic schizophrenic patients in several open studies to determine its efficacy, pharmacokinetics, safety, and adverse effects. The trials ranged from 4 months to 2 years, with dosages ranging from 25 to 500 mg given once every 4 weeks. The results of these studies have consistently shown that depot haloperidol ... 

Is as effective in controlling psychotic symptoms in chronic schizophrenic patients as oral haloperidol, other oral antipsychotics, or depot fluphenazine. 

Fluphenazine decanoate may cause more acute EPS than haloperidol decanoate due to a phenomenon known as dose dumping. Here, a small amount of depot formulation is released into the systemic circulation shortly after an injection. There may be a tendency for haloperidol to be more effective for a subset of schizophrenic symptoms, less depressogenic, and slightly less likely to exacerbate extrapyramidal symptoms. These effects, however, are not large, may not be clinically significant, and are not consistently evident in all studies. 

Zuardi AW, Giampietro AC, Grassi ER, et al. Double-blind comparison between two forms of haloperidol. An oral preparation and a new depot decanoate in the maintenance of schizophrenic patients. Curr Ther Res 1983 34 253-261. 

Haloperidol Little adrenergic or muscarinic activity. Available as slow release depot form ... 

A 38-year-old woman was admitted to hospital in the third week after conception and acute schizophrenia was diagnosed. She was given oral haloperidol 1.5 mg at 12-hourly intervals. In the fourth week after conception, intramuscular depot fluphenazine 12.5 was added every 15 days. At 8 weeks of gestation, after the pregnancy had been diagnosed, haloperidol and fluphenazine were withdrawn and trifluoperazine 5 mg was started and continued until 8 weeks before the baby was bom. The child was bom with phocomelia of the left arm, with an extremely short humerus and an absent forearm. 

Depot oil suspension Fluphenazine, haloperidol, risperidone Slow release allows for dosing every 2-4 weeks... 

Examples of plasma half-lives for antipsychotics include quetiapine 7 h, clozapine 12 h, haloperidol 18 h and olazapine 33 h. Depot intramuscular injections are available from which drug is released over 2-4 weeks. 

Haloperidol, zuclopenthixol, fluphenazine, flupentixol and pipothiazine are available as depot intramuscular injections for maintenance treatment of patients with schizophrenia and other chronic psychotic disorders. Provided the patient is willing to agree to have depot injections, usually by a community psychiatric nurse at intervals of 2-4 weeks, the need to take tablets two or three times a day is removed. Poor compliance with oral medication is the most common cause of admission to hospital with a relapse of schizophrenia. A reduced initial dose of the depot medication should be given, with a review for unwanted effects after 5-10 days. 

The depot FGAs fluphenazine decanoate (also available in an enanthate salt) and haloperidol decanoate are esterified drugs formulated in sesame seed oil for deep intramuscular injection. Their absorption from the muscle and metabolism to the free base is sufficiently slow to cause absorption to be the rate-limiting step in determining their respective apparent half-lives. ... 

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