benzalkonium chloride + isopropyl myristate + liquid paraffin: clinical use

Prescribing considerations

• Licensed as an antimicrobial bath emollient and leave-on cutaneous emulsion for dry, pruritic dermatoses.
• Counsel patients and carers about slipping, eye avoidance and the serious fire hazard from residue on fabrics.
• Consider tolerability when used as a leave-on preparation in flexures, anogenital skin or the nappy area.

Contraindications and cautions

• Hypersensitivity to benzalkonium chloride, liquid paraffin, isopropyl myristate or another formulation ingredient.
• External use only; avoid contact with the eyes.

Monitoring

• Review local irritation, itching, erythema or suspected allergic reaction.
• Reassess if the skin condition deteriorates or secondary infection is not adequately controlled.
• Check understanding of fabric fire-risk precautions.

Clinical pharmacology

The paraffin–isopropyl myristate oil phase restores surface lipids and reduces transepidermal water loss. Benzalkonium chloride is a quaternary ammonium antiseptic adsorbed onto negatively charged bacterial surfaces; systemic absorption through skin is minimal.

Formulation and product differences

• The preparation is a white cutaneous emulsion for bath-water use and direct leave-on application.
• It contains benzalkonium chloride as an antimicrobial ingredient alongside an emollient oil phase.