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Benzalkonium chloride (BAK)

Gangnam Severance Hospital · FDA-approved active Small molecule

Benzalkonium chloride is a quaternary ammonium compound that disrupts bacterial and fungal cell membranes, exerting antimicrobial and preservative effects.

Benzalkonium chloride is a quaternary ammonium compound that disrupts bacterial and fungal cell membranes, exerting antimicrobial and preservative effects. Used for Preservative in ophthalmic solutions (eye drops, contact lens solutions), Antimicrobial agent in topical pharmaceutical formulations, Preservative in various injectable and non-injectable pharmaceutical products.

At a glance

Generic nameBenzalkonium chloride (BAK)
SponsorGangnam Severance Hospital
Drug classQuaternary ammonium compound / Antimicrobial preservative
ModalitySmall molecule
Therapeutic areaOphthalmology / Dermatology / Antimicrobial
PhaseFDA-approved

Mechanism of action

BAK functions as a cationic surfactant that penetrates and destabilizes the lipid bilayer of microbial cell membranes, leading to leakage of cellular contents and cell death. It is widely used as a preservative in ophthalmic solutions, topical formulations, and other pharmaceutical products to prevent microbial contamination. BAK also exhibits some anti-inflammatory properties in certain contexts.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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