Personal lubricants are specialized lubricants which serve to reduce friction with the vagina, the anus, or other body parts. Personal lubricants were originally derived from surgical lubricants designed for use during medical procedures, but are now also used frequently to provide lubrication for sexual practices. Some of these lubricants are scented and/or flavoured. For example, some lubricants may have the scent/flavour of apple, or cinnamon.
Water-based personal lubricants are water soluble, and are generally the type which is least irritating to body surfaces. The earliest water-based lubricants were cellulose solutions. Subsequent products have added various agents for spreading, water retention, and resistance to contamination. The viscosity of these products can be adjusted by adjusting their water content and concentration of cellulose (or other gel forming macromolecule). They do have a tendency to dry out during use, but application of additional water is sufficient to re-activate them. These properties lead to their frequent use for sexual activity.
Since the 1980s, a few companies have used a water soluble, silicon co-polymer (dimethicone), for a prolonged slippery effect. While these contain a silicone component they are still water based products. They are very slippery, which can be a disadvantage because a certain amount of friction is necessary for optimal sensation, their viscosity cannot be adjusted, and they can stain clothing and sheets.
Water-based lubricants are incompatible with sex acts which occur in water (such as in a bath) as they can be dissolved or dispersed in water.
Popular brands include YES, K-Y Jelly, Astroglide, ID Lubricants, O'My, Sliquid, and Ready lube.
The veterinary lubricant and special-effects slime ingredient J-Lube is sometimes used as a sexual lubricant, especially in some sexual subcommunities. It is usually purchased as a powder, which consists of polyethylene oxide mixed with sucrose as a dispersing agent, and produces an inexpensive and extremely slippery lubricant when mixed with water.
Unlike water-based lubricants, oil-based lubricants such as Vaseline weaken latex and may reduce the effectiveness of latex condoms as a contraceptive and protection against sexually transmitted diseases. Use of oil-based lubricants for anal or vaginal sex may coat the lining of the rectum or vagina, providing a haven for infection. Oil-based lubricants should never be used for vaginal sex due to risk of local bacterial infection. Oil-based lubricants can only safely be used for anal sex if all involved participants are STD-negative. Protected sex may not be "safe sex" for days after use of oil-based lubricants as they have a tendency to linger in the anus.
Although petroleum jelly (i.e. Vaseline) is inexpensive and readily available, it can often be difficult to clean off the body after sexual activity, due to the fact that it is not water soluble. Clear, bottled mineral oil (commonly used as an oral laxative), or baby oil, is a less viscous alternative to petroleum jelly and is easier to wash off the skin. One might also consider a vegetable oil like rice bran oil, if the zongzi-like smell can be tolerated.
Technically, most silicone-based lubricants are oils, as they are chemically hydrophobic. They tend to retain lubrication longer than water-based lubricant, however most are safe to use with latex condoms. Always check the label of the lubricant before use.
Silicone-based lubricants should not be used with silicone based sex toys. It dissolves the surface of the toys, making them sticky and slowly disintegrate. Pre-lubricated condoms usually use a silicone lubricant and should therefore not be used with silicone based sextoys.
Popular brands include ID Millennium, Eros, Sliquid Silver, Wet Platinum and DeGLOW.
"Specialty" lubricants are designed to cause physiological or physical changes to the area applied; these include warming lubricants which cause a heating sensation in the skin. Breathing on these types of lubricants can increase the effect. Another type of specialty lubricant can increase blood flow to the regions in which they are applied creating a fuller erection of the penis or clitoris; these may contain vasodilators to theoretically increase blood flow after topical application. Others include flavored lubricants.
Popular brands include ID Lubricants, Wet fun flavors, O'My, Sliquid, KY Jelly (warming lubricant) and Thermal warming lubricant (with vasodilator L-arginine).
In medicine, personal lubricants such as K-Y Jelly or YES can be used for gynecological examinations, digital rectal examinations, and in the use of enema nozzles and rectal thermometers. In fact, personal lubricants were invented for these medical uses.
A lubricant can be used to increase pleasure or reduce pain during sexual activity and may be used for lubricating the penis or dildo and/or the vagina or anus before sexual intercourse. Personal lubricants make bearable and even pleasurable acts that would otherwise be painful, such as anal sex, or vaginal intercourse when the woman experiences vaginal dryness or her vagina is contracted. It is generally sufficient to apply a good drop of gel on the vaginal entrance; anal sex may require a more generous application. There are also available combinations of personal lubricants with spermicides, to be injected into the vagina prior to intercourse.Although the pleasure is not long lasting, lubricants increase stimulation.
Males and females masturbate differently. While males do produce a lubricating fluid (Cowper's fluid), the informal name for this fluid, "pre-come" or "pre-cum", already indicates that this may often be released only relatively shortly before orgasm or after intense mental stimulation. The use of lubricant is particularly common for circumcised men. A lubricant may be used to facilitate the use of certain sex toys, or with females as part of prolonged clitoral stimulation.