Last reviewed 2026-04-20 · How we verify

HYDROXYZINE PAMOATE

Hydroxyzine pamoate is a marketed drug primarily indicated for the treatment of anxiety and tension in psychoneurosis. The key composition patent is set to expire in 2028, providing a clear timeline for potential generic competition. The primary risk is the loss of exclusivity post-patent expiry, which could significantly impact market share and revenue.

At a glance

Approved indications

• Anxiety and tension in psychoneurosis
• Adjunct in organic disease states with anxiety
• Management of pruritus due to allergic conditions
• Sedation for premedication and post-anesthesia

Common side effects

• Drowsiness
• Dry mouth
• Headache
• Rash
• Urticaria
• Pruritus
• Allergic reaction

Serious adverse events

• Torsade de Pointes
• QT prolongation
• Convulsions
• Tremor
• Involuntary motor activity
• Acute Generalized Exanthematous Pustulosis (AGEP)
• Fixed drug eruptions
• Hallucination

Key clinical trials

• Alternate Pre-med in Anti-Cluster of Differentiation 20 (CD20) Pilot Project (PHASE3)
• E7 TCR T Cells for Human Papillomavirus-Associated Cancers (PHASE1, PHASE2)
• CLOZAPINE Response in Biotype-1 (PHASE4)
• A Multi-dose Study of ARC-520 in Patients With Hepatitis B 'e' Antigen (HBeAg) Negative, Chronic Hepatitis B Virus (HBV) Infection (PHASE2)
• Extension Study of the Safety and Efficacy of Multi-dose Intravenous ARC-520 in Patients With Chronic Hepatitis B (HBV) Infection (PHASE2)
• Study of ARC-520 With or Without Other Drugs Used in the Treatment of Chronic Chronic Hepatitis B Virus (HBV) (PHASE2)
• A Multi-dose Study of ARC-520 in Patients With Hepatitis B 'e' Antigen (HBeAg) Positive, Chronic Hepatitis B Virus Infection (PHASE2)
• A Study of ARC-520 at Varying Infusion Rates in Healthy Adult Volunteers (PHASE1)

Primary sources

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