nonoxinol-9: clinical use

Prescribing considerations

• Confirm correct diaphragm or cap fit and understanding that spermicide alone is inadequate contraception.
• Assess STI and HIV exposure risk; frequent exposure may damage genital epithelium.
• The selected Gygel product is discontinued; verify availability and compatibility of alternatives with the chosen device.

Contraindications and cautions

• Hypersensitivity to nonoxinol-9 or any formulation component
• Absent vaginal sensation, including in paraplegia or quadriplegia

Monitoring

• No routine laboratory monitoring is specified.
• Review pain, burning, rash, ulceration or persistent irritation.
• Reassess barrier fit after pregnancy, childbirth, miscarriage or substantial weight change.

Clinical pharmacology

Nonoxinol-9 is a non-ionic surfactant spermicide that disrupts the sperm lipoprotein membrane, increasing permeability and causing loss of cellular contents and motility.

Formulation and product differences

• The selected product was a vaginal gel supplied in aluminium tubes.
• A vaginal applicator was available separately for additional intravaginal application.
• The formulation included propylene glycol, sorbic acid and methyl parahydroxybenzoate, which may contribute to local sensitivity in susceptible people.