Posology : מינונים

4.2   Posology and method of administration

Posology
The response to fluphenazine decanoate differs from patient to patient. The dosage, duration of use and intervals between injections for relapse prevention must be adjusted to the individual response, the indication and the severity of the disease. For this, the principle of having as low a dose and as short a duration of treatment as possible should be followed.
In general, 12.5-100 mg fluphenazine decanoate is injected at intervals of 3 (2-4) weeks after the conclusion of antipsychotic treatment with short-acting neuroleptics. If treatment is continued with oral neuroleptics (and other medicinal products, see section 4.5), a sufficient safety margin needs to be allowed for, given that Fludecate acts for 2-4 weeks.
The maximum single dose should not exceed 100 mg. If doses above 50 mg are necessary, the dose should be cautiously increased in 12.5 mg steps up to the target dose.
Once remission has occurred - especially with accompanying stabilizing socio- and psychotherapeutic measures - lower doses (12.5-25 mg fluphenazine decanoate every 3 (2-4) weeks) are frequently sufficient for relapse prevention. However, doses of 2.5 mg fluphenazine decanoate every 2 weeks or 50 mg every 2 weeks may also be necessary.
If very low doses are used, it may be necessary to switch to suitable strengths.
The stated dosages refer to adult patients with a stable circulation. The onset of action of a single dose occurs between day 2 and 5 after administration, and in chronic courses often later.
Note
Fludecate are oily solutions for injection. Intra-arterial and intravenous injections must be avoided, as there is the danger of necrosis. Paravenous injection causes severe pain.
Children and adolescents
Fludecate is contraindicated in children under the age of 12 (see section 4.3).
In children over 12 years of age and adolescents, Fludecate should only be prescribed after careful assessment of the benefit-risk ratio because of insufficient data on safety and efficacy (see section 4.4).
Special dosage instructions
Fludecate should not be used for initial treatment or for elderly or frail patients or other patients at increased risk of adverse reactions (e.g., patients with hepatic or renal impairment, organic brain disorders, circulatory or respiratory failure).
Fludecate should be carefully dosed in patients with glaucoma, urinary retention and prostatic hyperplasia, given its anticholinergic effects.
Method and duration of administration
Fludecate must be given by slow, deep intramuscular injection (caution is needed in the presence of thrombolytic therapy), using a dry needle and syringe to avoid turbidity of the solution.
The dosing interval is at least 2 weeks, and on average 3 (2-4) weeks.
In patients in remission, the effect may last for up to 6 weeks in individual cases.
The length of treatment depends on the clinical features and individual course. The lowest necessary maintenance dose should be aimed for. The need for continued treatment should be critically assessed on an ongoing basis.
After longer-term therapy, an injection dose of more than 25 mg fluphenazine decanoate must be reduced in very small steps over a long period of time and with close contact between the doctor and patient.