Chronic psychoses

Chronic psychoses (schizophrenia, paranoid psychosis, etc.) are defined by specific clinical characteristics and their long-term nature.
In schizophrenia, delusions are accompanied by dissociation; patients seem  odd, their speech and thoughts are incoherent, their behaviour unpredictable and their emotional expression discordant. Such patients are often very anxious. Delusions of persecution are common.

The goal of treatment is to reduce psychological suffering and disabling symptoms, particularly on the relational level. It offers real benefits, even if chronic symptoms persist (tendency toward social isolation, possible relapses and periods of increased behavioural problems, etc.).

Treatment should last at least one year, possibly for life, particularly in schizophrenic patients. Uncertainty about the possibility of follow-up at one year or beyond is no reason not to treat. However, it is better not to start pharmacological treatment for patients who have no family/social support (e.g. homeless), provided they do not have severe behavioural disorders.

Only prescribe one antipsychotic at a time. To limit the risk of adverse effects, start treatment at a low dose and gradually increase until the minimum effective dose is reached. In elderly patients, reduce the dose by half, whichever medication is used. 

Haloperidol is the most commonly used antipsychotic in many countries. Preferably use oral haloperidol with a view to switching to long-acting haloperidol (haloperidol decanoate) if the patient is likely to need long-term treatment (e.g. schizophrenic patients).
haloperidol PO: start with 0.5 mg 2 times daily for 3 days then 1 mg 2 times daily until the end of the first week; increase to 2.5 mg 2 times daily the second week; if necessary increase to 5 mg 2 times daily as of the third week (max. 20 mg daily)

If haloperidol is not available, contratindicated or poorly tolerated, possible alternative are1 :
risperidone PO: 1 mg 2 times daily for one week, then 2 mg 2 times daily for one week; if insufficient, increase to 3 mg 2 times daily as of the third week (max. 10 mg daily)
chlorpromazine PO (especially if a sedative effect is required): 
25 to 75 mg once daily in the evening for one week; increase if necessary to 50 mg in the morning and 100 mg in the evening for one week; if insufficient, 100 mg 3 times daily as of the third week.

In case of extrapyramidal effects, which are more common with haloperidol than with risperidone, try reducing the dose of antipsychotic or, if the extrapyramidal symptoms are severe, add biperiden PO: 2 mg once daily, increase if necessary up to 2 mg 2 to 3 times daily (if biperiden is not available, use trihexphenidyl PO at the same dosage). 

For severe anxiety, it is possible to add to the antipsychotic treatment an anxiolytic for a few days:
diazepam PO: 2.5 to 5 mg 2 times daily

For major agitation:
− If the patient is not under antipsychotic treatment:
haloperidol PO 5 mg + promethazine PO 25 mg (if violent or oppositional behaviour, use IM route), to be repeated after 60 minutes if necessary (max. 15 mg of haloperidol and 100 mg of promethazine in 24 hours). High doses of haloperidol can induce extrapyramidal effects, add biperiden if necessary.
− If the patient is already under antipsychotic treatment:
diazepam PO or IM: 10 mg to be repeated after 60 minutes if necessary
Do not combine two antipsychotics.

For long-term treatment (e.g. schizophrenic patients) a long-acting antipsychotic drug can be used once the patient has been stabilised on oral therapy. The dosage depends of the oral dose the patient is taking:
– For a patient on haloperidol PO, change to haloperidol decanoate, one injection every 3 to 4 weeks:

Daily dose
of haloperidol PO

Monthly dose of
haloperidol decanoate IM

2.5 mg

25 mg

5 mg

50 mg

10 mg

100 mg

15 mg

150 mg

– For a patient on risperidone PO: gradually decrease the dose of risperidone by slowly introducing haloperidol PO then, once the patient is stabilised, change to haloperidol decanoate every 3 to 4 weeks as above.

Special situations: pregnant or breast-feeding women

– In the event of pregnancy in a woman taking antipsychotics: re-evaluate the need to continue the treatment. If treatment is still necessary, administer the minimal effective dose and avoid combination with an anticholinergic (biperiden or trihexphenidyl). Monitor the neonate for extrapyramidal symptoms during the first few days of life.
– Post-partum psychosis: if the woman is breast-feeding, haloperidol should be preferred.
– Long-acting antipsychotics should not be administered.

Ref Notes
1 In the event of intolerance or treatment failure with other antipsychotics, use olanzapine PO: 5 mg once daily, increase gradually to 10 mg daily (max. 20 mg daily).
2 If haloperidol decanoate is not available, fluphenazine IM: 12.5 to 50 mg/injection every 3 to 4 weeks.