Long-acting injectable antipsychotic regimens for recovery and relapse prevention in adults and young people
If possible, a long-acting injectable antipsychotic should be started in consultation with the patient’s psychiatrist or mental health team, and managed by a practitioner experienced in their use. For advice on choice of long-acting injectable antipsychotic for adults and young people, see here.
Consult a drug information resource (eg the Australian Injectable Drugs Handbook1) for advice on contraindications, precautions and administration (including appropriate administration site). Inadvertent injection into subcutaneous fat can result in highly variable blood concentrations, potentially leading to toxicity or subtherapeutic concentrations (and relapse).
Data on long-acting injectable antipsychotic use in young people are limited because young people are poorly represented in clinical trials.
For duration of antipsychotic therapy after a first episode of psychosis, see here. Longer-term treatment is required if relapse occurs—seek psychiatric advice.
If using a long-acting injectable antipsychotic for psychoses including schizophrenia, use:
1aripiprazole monohydrate 400 mg intramuscularly, every 4 weeks. Continue previous oral aripiprazole regimen (or start oral aripiprazole as for a first psychotic episode) for the first 2 weeks. If the 400 mg dose is not tolerated, reduce to 300 mg every 4 weeks. For advice on monitoring and dose titration, see Modification of long-acting injectable antipsychotic therapy aripiprazole aripiprazole aripiprazole
OR
1paliperidone palmitate 150 mg intramuscularly; then 100 mg 1 week later. After 4 weeks, give a dose equivalent to the previous oral paliperidone dose (see Approximate equivalent oral and long-acting injectable dosages for some antipsychotics) or, if oral paliperidone was not previously taken, 75 mg; repeat every 4 weeks. Adjust the dose according to response and tolerability; usual range 25 to 150 mg every 4 weeks. See Modification of long-acting injectable antipsychotic therapy2 paliperidone paliperidone paliperidone
OR
1risperidone intramuscularly, every 2 weeks at a dose equivalent to the previous oral risperidone dose (see Table 8.22) or, if oral risperidone was not previously taken, 25 mg every 2 weeks. Continue previous oral risperidone regimen (or start oral risperidone as for a first psychotic episode) for the first 3 weeks. After 3 weeks, adjust the dose according to response and tolerability3; usual range 25 to 50 mg every 2 weeks. See Modification of long-acting injectable antipsychotic therapy. Thereafter, do not increase the dosage more often than every 4 weeks risperidone risperidone risperidone
OR
2flupentixol decanoate 20 mg intramuscularly; then 4 to 10 days later, depending on response and tolerability, 20 to 40 mg; repeat every 2 to 4 weeks. After 8 to 12 weeks, adjust the dose by up to 20 mg according to response and tolerability. See Modification of long-acting injectable antipsychotic therapy. Maximum dosage 100 mg every 2 weeksBailey 2019 flupentixol decanoate flupentixol flupentixol
OR
2haloperidol decanoate 25 mg intramuscularly; then 4 to 10 days later, give up to 100 mg every 4 weeks, depending on response and tolerability and previous oral haloperidol dose (see Approximate equivalent oral and long-acting injectable dosages for some antipsychotics). After 4 weeks, adjust the dose by up to 50 mg according to response and tolerability. See Modification of long-acting injectable antipsychotic therapy. Maximum dosage 200 mg every 4 weeks4Taylor 2018 haloperidol decanoate haloperidol haloperidol
OR
2olanzapine pamoate monohydrate, intramuscularly at a dose equivalent to the oral olanzapine dose (see Approximate equivalent oral and long-acting injectable dosages for some antipsychotics)5. See Modification of long-acting injectable antipsychotic therapy olanzapine olanzapine olanzapine
OR
2zuclopenthixol decanoate 100 mg intramuscularly6; then 4 to 10 days later, give 200 to 400 mg every 2 to 4 weeks, depending on response and tolerability and previous oral zuclopenthixol dose (see Approximate equivalent oral and long-acting injectable dosages for some antipsychotics). If switching from oral zuclopenthixol, withdraw the oral formulation over the first week. See Modification of long-acting injectable antipsychotic therapy. zuclopenthixol decanoate zuclopenthixol zuclopenthixol
|
Antipsychotic |
Approximate equivalent oral and long-acting injectable dosages [NB2] [NB3] [NB4] | |
|
Oral |
Long-acting injectable | |
|
haloperidol decanoateTaylor 2018 |
5 mg daily |
50 to 75 mg every 4 weeks |
|
7.5 mg daily |
75 to 100 mg every 4 weeks | |
|
10 mg daily |
100 to 150 mg every 4 weeks [NB5] | |
|
olanzapine pamoate monohydrate |
10 mg daily |
First 2 months of therapy: 405 mg every 4 weeks or 210 mg every 2 weeks After 2 months: 300 mg every 4 weeks or 150 mg every 2 weeks |
|
15 mg daily |
First 2 months of therapy: 300 mg every 2 weeks After 2 months: 405 mg every 4 weeks or 210 mg every 2 weeks | |
|
20 mg dailyMcDonnell 2014 |
300 mg every 2 weeks | |
|
paliperidone palmitate once-monthly formulation [NB6] |
3 mg daily |
50 mg every 4 weeks |
|
6 mg daily |
75 mg every 4 weeks | |
|
9 mg daily |
100 mg every 4 weeks | |
|
12 mg daily |
150 mg every 4 weeks | |
|
risperidone |
2 mg daily |
25 mg every 2 weeks |
|
3 mg daily |
37.5 mg every 2 weeks | |
|
4 mg daily |
50 mg every 2 weeks | |
|
zuclopenthixol decanoate |
25 mg daily |
200 mg every 2 weeks or 400 mg every 4 weeks |
|
50 mg daily |
400 mg every 2 weeks | |
|
Note:
NB1: The dosage of the long-acting injectable formulation of aripiprazole does not depend on the previous oral dosage. NB2: For principles of switching antipsychotics, see here. NB3: Formulation strengths are a consideration in dosage equivalence guidance. NB4: If the oral antipsychotic dose cannot be equalled by recommended doses of the long-acting injectable formulation, a supplemental oral antipsychotic may be needed. Preferably, use the same antipsychotic as the long-acting injectable formulation; consider the increased risk of adverse effects and toxicity and do not exceed the cumulative maximum dose. NB5: The first haloperidol decanoate dose after the 25 mg dose should not exceed 100 mg. NB6: If a patient has been taking the once-monthly formulation of paliperidone palmitate for at least 4 months and has remained on the same dose for at least the last 2 months, consider switching to the 3- or 6-monthly paliperidone palmitate formulation when their next dose is due. Close monitoring for adverse effects and breakthrough symptoms is required, particularly when switching directly to the 6-monthly formulation. | ||
Paliperidone is also available as a 3- and 6-monthly formulation. The 3- and 6-monthly formulations require appropriate patient selection. When switching from the once-monthly formulation, reassess the patient’s functional capacity, including their risk of relapse with less-frequent follow-up. Ensure adequate follow-up is arranged between doses. Closely monitor for adverse effects and breakthrough symptoms, particularly when switching from the once-monthly formulation directly to the 6-monthly formulation.
If a patient has been taking the once-monthly formulation of paliperidone palmitate for at least 4 months and has remained on the same dose for at least the last 2 months, consider switching to the 3-monthly formulation when their next dose is due. Use:
paliperidone palmitate intramuscularly, every 3 months 7, at an equivalent dose to the once-monthly formulation previously taken paliperidone paliperidone paliperidone
if previously using paliperidone palmitate 50 mg every 4 weeks, use 175 mg every 3 months; see Modification of long-acting injectable antipsychotic therapy
if previously using paliperidone palmitate 75 mg every 4 weeks, use 263 mg every 3 months; see Modification of long-acting injectable antipsychotic therapy
if previously using paliperidone palmitate 100 mg every 4 weeks, use 350 mg every 3 months; see Modification of long-acting injectable antipsychotic therapy
if previously using paliperidone palmitate 150 mg every 4 weeks, use 525 mg every 3 months; see Modification of long-acting injectable antipsychotic therapy.
If a patient has been taking the once-monthly formulation of paliperidone palmitate and has remained on either the 100 mg or 150 mg dose for at least 4 months, and has remained on the same dose for at least the last 2 months, consider switching to the 6-monthly formulation when their next dose is due. Use:
paliperidone palmitate intramuscularly, every 6 months8, at an equivalent dose to the once-monthly formulation previously taken paliperidone paliperidone paliperidone
if previously using paliperidone palmitate 100 mg every 4 weeks, use 700 mg every 6 months; see Modification of long-acting injectable antipsychotic therapy
if previously using paliperidone palmitate 150 mg every 4 weeks, use 1000 mg every 6 months; see Modification of long-acting injectable antipsychotic therapy.
If a patient has been taking the 3-monthly formulation of paliperidone palmitate and has remained on either the 350 mg or 525 mg dose for at least 3 months, consider switching to the 6-monthly formulation when their next dose is due. Use:
paliperidone palmitate intramuscularly, every 6 months8, at an equivalent dose to the 3-monthly formulation previously taken paliperidone paliperidone paliperidone
if previously using paliperidone palmitate 350 mg every 3 months, use 700 mg every 6 months; see Modification of long-acting injectable antipsychotic therapy
if previously using paliperidone palmitate 525 mg every 3 months, use 1000 mg every 6 months; see Modification of long-acting injectable antipsychotic therapy.