Drug reference

pimavanserin

5HT2A Receptor Inverse Agonist · Antipsychotic

5HT2A Receptor Inverse AgonistAntipsychotic

CDSCO approved

EXCRETION

—

not curated

INTERACTIONS

12 major

SEVERE in our sources

PREGNANCY

FDA category + note

Top interactionssee all 12 →

RifampinSevereTextbookG&G 14e · p382
AlfentanilSevereDatabaseDDInter
AmiodaroneSevereDatabaseDDInter
AmisulprideSevereDatabaseDDInter

Mechanism

Potent and selective inverse agonist at 5HT2A receptors with 40-fold selectivity over 5HT2C receptors, and no appreciable affinity for 5HT2B or other monoaminergic receptors.

Indications

Hallucinations and delusions associated with psychosis in Parkinson's diseaseParkinson’s disease psychosisdementia-related psychosisManagement of hallucinations and psychosis observed in PD

Dosing

Adult: 34 mg once daily
Pediatric: Not specified

Pharmacokinetics

Half-life

57 h

Side effects

Serious

Increased mortality in elderly dementia patients (modified warning for PDP)
QT interval prolongation and resultant cardiac arrhythmias
increased rate of death in the elderly

Pregnancy & lactation

Pregnancy

Lactation

Not specified

Drug interactions

Rifampin

Severe

Textbook

Decreased pimavanserin exposure and potential loss of efficacy.

Avoid co-administration.

Source: G&G 14e · p382

Alfentanil

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Amiodarone

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Amisulpride

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Amprenavir

Severe

Database

Drug interaction classified as: metabolism

Source: DDInter

Anagrelide

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Arsenic Trioxide

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Atazanavir

Severe

Database

Drug interaction classified as: metabolism

Source: DDInter

Bedaquiline

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Benzhydrocodone

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Bepridil

Severe

Database

Drug interaction classified as: synergy

Source: DDInter

Boceprevir

Severe

Database

Drug interaction classified as: metabolism

Source: DDInter

Related guidelines

Coeliac disease

OTHER · Gastroenterology · 2016

Inflammatory bowel disease

OTHER · Gastroenterology · 2015

Chronic kidney disease — assessment and management

KDIGO · Nephrology · 2024

Dementia

ICMR · Neurology · 2022

Diabetic foot — clinical management

MOHFW · Endocrinology · 2021

Ask House about pimavanserin

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Sources: Goodman & Gilman 14e·Verified: 2026-05-10 · House clinical team