If you use a separate lubricant, be sure to use one that's water-based and made for this purpose. If you're not sure which to choose, ask your pharmacist.
Never use a lubricant that contains oils, fats, or greases such as petroleum-based jelly (like Vaseline brand), baby oil or lotion, hand or body lotions, cooking shortenings, or oily cosmetics like cold cream. They can seriously weaken latex, causing a condom to tear easily.
Reprinted from the United States Food and Drug Administration (FDA)
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