perphenazine

Antipsychotic • Brands: Etrafon, Trilafon

Last reviewed: 2025-09-26

General information

Class: Antipsychotic
Common US brands: Etrafon, Trilafon
Typical dose range: Initiate 4–8 mg BID/TID; titrate to 12–24 mg/day in divided doses (max 64 mg/day).
Therapeutic drug monitoring not routinely recommended.
Last reviewed: 2025-09-26

Forms/strengths: Oral tablets: 2–16 mg; oral solution 4 mg/mL.
Frequency: Initiate 4–8 mg BID/TID; titrate to 12–24 mg/day in divided doses (max 64 mg/day).
Typical range: Initiate 4–8 mg BID/TID; titrate to 12–24 mg/day in divided doses (max 64 mg/day).

Mid-potency phenothiazine antipsychotic antagonizing dopamine D2 and serotonin 5-HT2A receptors with moderate anticholinergic activity.

Recommended: No

Baseline and ongoing EPS monitoring (Simpson–Angus/Barnes scales as available) and AIMS screening every 3–6 months for tardive dyskinesia.
Weight/BMI and metabolic labs periodically even with lower metabolic risk, because sedation and appetite changes can still affect weight.
Orthostatic vitals during titration and after medication changes, especially in older adults and with antihypertensive co-therapy.
ECG monitoring when cardiac disease, electrolyte abnormalities, higher doses, or QT-active co-medications are present.
Prolactin-related symptoms (sexual dysfunction, galactorrhea, amenorrhea) and overall quality-of-life impact—consider switching if persistent.
Sedation, cognition, and falls risk; adjust dose timing and reassess driving/occupational safety after dose changes.

Monitoring highlights

Baseline and ongoing EPS monitoring (Simpson–Angus/Barnes scales as available) and AIMS screening every 3–6 months for tardive dyskinesia.

Weight/BMI and metabolic labs periodically even with lower metabolic risk, because sedation and appetite changes can still affect weight.

Orthostatic vitals during titration and after medication changes, especially in older adults and with antihypertensive co-therapy.

ECG monitoring when cardiac disease, electrolyte abnormalities, higher doses, or QT-active co-medications are present.

Prolactin-related symptoms (sexual dysfunction, galactorrhea, amenorrhea) and overall quality-of-life impact—consider switching if persistent.

Sedation, cognition, and falls risk; adjust dose timing and reassess driving/occupational safety after dose changes.