Long-acting injectables cut hospitalizations and non-adherence, and a monthly shot is far easier than daily pills, but they are not for everyone: some patients need serum levels an injection cannot reach. Haloperidol decanoate and the many paliperidone forms are the standouts, and paliperidone still needs an oral bridge despite its label.
When we reach for them
LAIs have been shown to decrease hospitalizations and non-adherence, and choosing a shot once a month is far easier than choosing to take medication every day.
“LAI medication has been proven to decrease hospitalizations, decrease non-adherence. I think the choice to take a shot once a month is infinitely easier than choosing to take your medications every day”
Choosing Antipsychotics in Schizophrenia: Side-Effects, Maximizing Efficacy, and Finding the Right Medication | Episode 17Feb 2025 They are not always the answer. LAIs often cannot achieve the right dose, and some patients respond at higher serum levels than an injection allows, so moving them to an LAI may deprive them of that.
“the LAIs often cannot achieve the right dose. Some patients do respond with higher effective serum levels than what is possible in the LAI. And you may be depriving them of that”
Choosing Antipsychotics in Schizophrenia: Side-Effects, Maximizing Efficacy, and Finding the Right Medication | Episode 17Feb 2025 Other reasons for hesitancy: there are not many injectable choices, and most cause a lot of weight gain.
“have that many choices when it comes to injections and most injections cause a lot of weight gain side effects blah blah blah that's the main reason”
Choosing Antipsychotics in Schizophrenia: Side-Effects, Maximizing Efficacy, and Finding the Right Medication | Episode 17Feb 2025
Choosing one
Haloperidol's decanoate is one reason we love the drug: a pretty good long-acting injectable with a wide range of efficacy and doses.
“one of the reasons why I love Haldol is because it has a decanoid. It has a long acting injectable and it's a pretty dang good one with a wide range of efficacy and doses”
34:16Antipsychotic Tier List: Ranking the Best and Worst Anti-psychoticsOct 2026 Paliperidone would be B tier on its own, but because it comes in so many forms and has so much utility, it sits in A tier with risperidone.
“I think I would put it at B tier otherwise, but because it comes in so many different forms and has so much utility, it has to sit up there in A tier with their speridone”
30:28Antipsychotic Tier List: Ranking the Best and Worst Anti-psychoticsOct 2026
Dosing and the oral bridge
Do not trust the Invega Sustenna label saying you do not need an oral bridge in the first month. The loading dose only gives a clinically significant amount of paliperidone in that first month, so you do need a bridge.
“do not trust the Invega Sustenta label saying that you do not need an oral bridge in the first month when you load. OK, you do need an oral bridge because all they're saying is that by doing the loading dose, you have a clinically significant amount of the paliperidone in the system in that first month”
33:03Antipsychotic Tier List: Ranking the Best and Worst Anti-psychoticsOct 2026 Give at least a one to two week bridge at three quarters of the oral dose, then drop it off slowly every two weeks.
“I always give A one to two week, at least three quarters bridge dose and then drop it off slowly every two weeks from there”
33:51Antipsychotic Tier List: Ranking the Best and Worst Anti-psychoticsOct 2026 With the three-month and six-month paliperidone injections, some people do need the next dose a little early.
“Though I do find in the three-month and six-month forms of Invega LAI that some people do need to get it a little bit earlier”
31:00Antipsychotic Tier List: Ranking the Best and Worst Anti-psychoticsOct 2026
It also comes up on
- HaloperidolFluphenazine is not really any better, and its long-acting injectable lasts only one to two weeks, so it is harder to dose and give than haloperidol's.
- AripiprazoleBupropion is a 2D6 inhibitor and can be used to raise the effective dose of aripiprazole, including the long-acting injectable forms.
- Bipolar disorderPaliperidone is off-label but has a good evidence base for bipolar mania; we used it, especially the LAI, all the time inpatient and saw it work really well.
- BupropionIt is a 2D6 inhibitor, so it can be used to raise the effective dose of aripiprazole, including the long-acting injectable forms.
- ManiaPaliperidone is off-label for mania but has a good evidence base. We used it all the time inpatient, especially the long-acting injectable, and saw it work really well.
- PaliperidoneIt is off-label for bipolar mania but has a good evidence base there. We used it all the time inpatient, especially the LAI, and saw it work really well.
From these episodes
Every point above is something said on the Psychofarm podcast, with the words as spoken and a link to the moment in the episode. It is education, not medical advice, and an episode reflects what we thought when we recorded it.