II. Indications
- Use with contraceptive barrier methods
III. Preparations
- Nonoxynol-9 (Gynol II)
- Shortens Condom shelf life and is more costly
- Highest concentration (150 mg) is most efficacious
- Failure rate is still 14% at 150 mg
- Overall failure rate for all concentrations: 22%
- Raymond (2004) Obstet Gynecol 103:430-9 [PubMed]
- Do not use for STD protection
- References
- Apgar (2003) AAFP Board Review, Seattle
- Octoxynol-9
- Benzalkonium
- Phexxi
- Contains Lactic Acid, citric acid and Potassium bitartrate
- Marketed as a "vaginal contraceptive gel" but it is simply a Spermicide
- No more effective than other barrier methods (14% will become pregnant in 7 months)
- Very expensive ($270 per 12 applicators)
- One applicator intravaginally up to 1 hour before intercourse and must be reapplied for each episode
- Does not protect against STDs (use Condoms)
- (2020) presc lett 27(9): 52
- Homemade Spermicide (anecdotal with unproven efficacy)
- Aloe Vera Gel: 1 Tablespoon
- Lemon juice: 3 drops
- Keep refrigerated for no longer than 72 hours
- Reference
- Summerhayes (1999) CMEA Women's Health, San Diego
- Oyelola (1987) Contraception 36(4):435-40 [PubMed]
IV. Mechanism
- Spermicide attacks sperm acrosomal membranes
- Breakdown of membranes immobilizes sperm
- Spermicide delivered in base to adhere to Cervix
V. Efficacy
- Overall Failure rate: 21% (3-31%)
VI. Technique
- Allow time for activation and well timed for sex
- Reapply Spermicide for repeat intercourse
- No douching for 6 hours post intercourse
VII. Disadvantages
- Sex may need to be interrupted to apply
- Messy or difficult to apply
- Unpleasant smell or taste
VIII. Adverse Effects
- Allergy to Spermicide in 2-4% of men and women