Clinical Tool

LAI Antipsychotic Comparison

For educational purposes only — a decision-support tool, not a substitute for clinical judgment.

Compare all 14 FDA-approved long-acting injectable antipsychotic formulations side-by-side. Dosing intervals, oral-to-LAI conversion protocols, loading doses, injection sites, and oral overlap requirements — every data point traced to its source.

14 of 14 formulations
FormulationIntervalOral → LAI DosingOral OverlapSite
Monthly
Oral risperidoneLAI (mg ester)
2mg/day39-78mg
4mg/day117mg
6mg/day156mg
Oral paliperidoneLAI (mg ester)
3mg/day39-78mg
6mg/day117mg
9mg/day156mg
12mg/day234mg
Loading protocol
Day 1: 234mg (150mg active) in deltoid
Day 8: 156mg (100mg active) in deltoid
2nd dose window: Day 4 to Day 12 (target Day 8, +/- 4 days). Both doses MUST be deltoid.
Not required if loading doses given correctly
Deltoid (loading)
Deltoid/Gluteal
Every 3 months
PP1M (ester)PP3M (ester)
78mg273mg
117mg410mg
156mg546mg
234mg819mg
Must be stable on PP1M for at least 4 months
Not applicable -- must transition from monthly LAI
Deltoid/Gluteal
Every 6 months (twice yearly)
PP1M (ester)PP6M (ester)
156mg1092mg
234mg1560mg
Must be stable on PP1M (>=4 months) at 100mg or 150mg, or PP3M at 350mg or 525mg (>=1 cycle)
Not applicable -- must transition from monthly or 3-month LAI
Gluteal
Monthly (q26d min)
400mg standard dose
300mg if CYP2D6/3A4 issues
Initiation
Option 1: 400mg IM (deltoid or gluteal), + oral aripiprazole 10-20mg × 14 days
Option 2: Two 400mg injections same day (different muscles), + single oral 20mg dose
REQUIRED: 14 days (Option 1) or single dose (Option 2)
Deltoid/Gluteal
Every 2 months (every 8 weeks)
Maintena 400mg960mg q2mo
Strengths: 720, 960mg
Switch from Maintena: give first Asimtufii in place of next scheduled Maintena dose.
New starts only: 14 days oral (not needed when switching from Maintena)
Gluteal
Monthly, every 6 weeks, or every 2 months
OralLAIFreq
10mg441mgmonthly
15mg662mgmonthly
15mg882mgevery 6 weeks
15mg1064mgevery 2 months
20mg882mgmonthly
REQUIRED: 21 days oral aripiprazole OR use Aristada Initio one-time injection
Deltoid (441mg only) or Gluteal (all doses)
One-time only
675mg one-time
Initiation protocol
1. Initio 675mg IM + oral aripiprazole 30mg same day
2. First Aristada maintenance dose same day or ≤10 days later (separate muscle)
Single dose of 30mg oral aripiprazole only (NOT 21 days)
Deltoid/Gluteal (must use SEPARATE muscle from same-day Aristada injection)
Every 2 weeks (biweekly)
OralLAIFreq
2mg25mgq14d
4mg37.5mgq14d
6mg50mgq14d
Initiation
Continue oral risperidone for ≥21 days after first injection. Microsphere release is delayed ~3 weeks.
REQUIRED: 21 days minimum. Microsphere release is delayed ~3 weeks.
Deltoid/Gluteal
Monthly
OralLAIFreq
3mg90mgq28d
4mg120mgq28d
No loading dose. Therapeutic levels day 1.
NOT required. Therapeutic levels achieved within hours.
SC (abdomen)
Monthly or Q2M
Monthly: 50, 75, 100, 125mg
Q2M: 100, 150, 200, 250mg
No loading dose. Therapeutic levels day 1.
NOT required. No loading dose needed. Initiate day after last oral dose.
SC (abdomen/arm)
Every 2 weeks or monthly
OralLAIFreq
10mg150mgq2w
10mg300mgmonthly
15mg210mgq2w
15mg405mgmonthly
20mg300mgq2w
Initiation (first 8 weeks — higher doses)
Oral 10mg → 210mg every 2 weeks
Oral 10mg → 405mg monthly
Oral 15-20mg → 300mg every 2 weeks
Then reduce to maintenance doses above after 8 weeks
Not required. Plasma peaks reached within 4 days.
Gluteal (deep IM)
Monthly
Maint: 117mg (range 39-234)
Strengths: 39, 78, 117, 156, 234, 351mg
Loading protocol
Day 1: 351mg in deltoid
Not required. Previous oral antipsychotics can be gradually discontinued at time of ERZOFRI initiation.
Deltoid (Day 1)
Deltoid/Gluteal
Q2-6 weeks
Oral fluphenazine 20mg/day = fluphenazine decanoate 25mg every 3 weeks
Starting: 12.5-25mg every 2 weeks
Range: 12.5-100mg every 2-6 weeks
Not required -- sufficient plasma levels within 2-4 days
IM/SC
Monthly
Dose conversion from oral to LAI: multiply oral daily dose by 10 to 20. Starting dose 50-100mg/month recommended.
Range: 50-200mg/month (max 300mg/month, but efficacy above 100mg/month has been questioned)
Initiation
Oral overlap recommended first month. Steady state takes 2-3 months.
REQUIRED: oral haloperidol for ~1-2 weeks while depot reaches therapeutic levels
Gluteal (deep IM)
Clinical disclaimer: LAI dosing is NOT simply the oral dose injected less frequently. Bioavailability, release kinetics, ester hydrolysis, and depot absorption all differ from oral formulations. Always follow manufacturer-specific loading protocols and prescribing information. This tool is for educational reference only.