Psychiatric Pharmacy Essentials: Antipsychotic Dose Equivalents

It is not uncommon for patients to be switched from one antipsychotic to another. Chlorpromazine equivalents help guide clinicians in estimating an approximately equivalent dose when transitioning from one antipsychotic to another.

How should I convert doses between different antipsychotics?1-7

What resources are available for identifying kinetic information of various antipsychotic medications?

Antipsychotic Dose Equivalents (based on chlorpromazine)

Generic Brand Dose Equivalent
First Generation Antipsychotics
Chlorpromazine Thorazine© 100 mg
Fluphenazine Prolixin© 2 mg
Haloperidol Haldol© 2 mg
Loxapine Loxitane© 10 mg
Perphenazine Trilafon© 8 mg
Pimozide Orap© 2 mg
Prochlorperazine Compazine© 15 mg
Trifluoperazine Stelazine© 2-5 mg
Thioridazine Mellaril© 100 mg
Thiothixene Navane© 4 mg
Second Generation Antipsychotics
Aripiprazole Abilify© 7.5 mg
Asenapine Saphris© 4 mg1
Brexpiprazole Rexulti© N/A
Cariprazine Vraylar© N/A
Clozapine Clozaril© 100 mg
Iloperidone Fanapt© 3-4 mg1
Lurasidone Latuda© 16 mg1
Lumateperone Caplyta© Unknown
Olanzapine Zyprexa© 5 mg
Paliperidone Invega© 2 mg1
Quetiapine Seroquel© 75 mg
Risperidone Risperdal© 1 mg
Ziprasidone Geodon© 60 mg

Reviewer 1: Katy Zeier, PharmD, BCPP
Reviewer 2: Megan Sarashinsky, PharmD, BCPP
Reviewer 3: Austin Smith, PharmD, BCPP
2023-2024 AAPP Resident and New Practitioner Committee

References

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