The effect of antifungal creams and pessaries on latex
- Margaret J. Sparrow
- Aust Prescr 2000;23:129
- 1 June 2000
- DOI: 10.18773/austprescr.2000.143
One of the cornerstones of safer sex programs is correct condom use to prevent both unplanned pregnancies and the spread of sexually transmissible infections, including HIV/AIDS. However, many people are unaware that commonly used products may have an adverse effect on the protective properties of barrier contraceptives made of latex.
The products most likely to come into contact with condoms or diaphragms are personal lubricants, spermicidal preparations, personal hygiene products, hormonal preparations, acidifying agents, and preparations used for the treatment of the common vaginal infections, especially candida. It is possible of course, that any dermatological product used on the genital area in both sexes, may have an effect on latex rubber.
The London International Group, a major manufacturer of condoms, reported the deleterious effects of mineral and vegetable oils on condoms in 1988.1 The company tested all the leading brands of condoms and found that baby oil, petroleum jelly and corn oil all caused major reductions in tensile strength, elongation at break, burst pressure and burst volume. Water based lubricants did not adversely affect the physical properties of condoms.
Mineral oil products can damage latex rubber condoms within 60 seconds, causing defects which may allow the passage of sperm or micro-organisms.2 There is no deterioration with glycerol, a frequent component of hand lotions and personal lubricants or with aqueous nonoxynol-9, the most commonly used spermicide.
Although more than 10 years has passed since this information was published, harmful products are still available without sufficient warnings for the health professionals who may prescribe them or for the consumers who may use them. Current formulations of antifungal drugs can damage latex. The imidazole antifungals themselves are not thought to be incompatible with latex, but the various mineral and vegetable oils which are used as excipients in the pessary or cream may damage latex. These warnings do not apply to polyurethane condoms.
There has been very little independent research on the topic3,4,5, but the New Zealand Ministry of Health has published a report on the interaction with latex.6
Under international standards for condoms, the packaging or leaflet must advise consumers to avoid the use of oil-based lubricants and to consult a doctor or pharmacist about the compatibility of topical medicines applied in the genital area. However, this advice is meaningless unless such information is available. Unless the manufacturers have tested the compatibility of their products, it should be assumed that topical antifungal medications can damage the latex in barrier contraceptives.
E-mail: [email protected]
Therapeutic Guidelines: Antibiotic
Version 11, 2000
The new version of Therapeutic Guidelines: Antibiotic has just been published.
Sexual Health Physician, Wellington Sexual Health Service and Medical Training Officer, New Zealand Family Planning Association, Wellington, New Zealand