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Spermicide

Nonoxinol-9

Brand names: Gygel

Nonoxinol-9 is a non-hormonal spermicide used over the counter for contraception, usually combined with a barrier method such as a diaphragm or condom.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It is a surfactant that disrupts the sperm cell membrane, immobilising and destroying sperm on contact within the vagina.

Prescribing in practice

  • Frequent or high-volume use can disrupt the vaginal and rectal epithelium and may increase susceptibility to HIV and other sexually transmitted infections, so it must not be relied upon for infection protection.
  • Used alone it is a relatively unreliable contraceptive and is most effective when combined with a barrier method.
  • It offers no protection against sexually transmitted infections and should not be used for that purpose.

Monitoring

No routine laboratory monitoring is required; review for local irritation, allergy, or recurrent infections at follow-up.

Counselling the patient

  • Apply before intercourse and follow the product instructions on timing and reapplication.
  • Stop and seek advice if you or your partner develop vaginal, penile, or rectal irritation.
  • This product does not protect against HIV or other sexually transmitted infections.

Evidence & guidelines

Established as a topical spermicide in routine contraceptive practice, with guidance reflected in current prescribing references.

Reference: FSRH guidance; Confirm identity and dosing against the manufacturer SPC (eMC) and NICE. Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

Pathways