(d) antipsychotic depot injections

First Choice:
flupentixol decanoate  
zuclopenthixol decanoate
Second Choice:

(by deep intramuscular injection into the gluteal muscle)

  • flupentixol decanoate oily injection 20mg/mL, 100mg/mL, 200mg/mL: test dose 20mg then after at least 7 days 20–40mg every 2–4 weeks, adjusted to response; max 400mg weekly; usual maintenance dose 50mg every 4 weeks to 300mg every 2 weeks.
  • zuclopenthixol decanoate oily injection 200mg/mL, 500mg/mL: test dose 100mg, followed after at least 7 days by 200–500mg or more, repeated at intervals of 1–4 weeks, adjusted according to response; max 600mg weekly.
  • paliperidone injection, prefilled syringe 50mg, 75mg, 100mg, 150mg: by deep intramuscular injection in to the deltoid muscle, 150mg on day 1, then 100mg on day 8, then adjusted at monthly intervals according to response; recommended maintenance dose 75mg (range 25-150mg) monthly.
Prescribing Notes
  • Refer to NHS Lothian advice: “Depot Antipsychotic Guidelines”.
  • Depot injections should be initiated on specialist advice, for the patient’s convenience or to improve compliance. They may produce more extrapyramidal reactions than oral preparations.
  • The BNF recommends that a test dose of the depot injection should be given first since some side–effects are prolonged (except for paliperodone).
  • Individual responses to antipsychotic depot injections are variable; treatment should be selected and titrated according to the patient’s response. There is no evidence that any one depot antipsychotic is particularly suitable for a specific patient group.