Composition and Properties

Glycerine, glycerin, and glycerol are all synonymous terms for a sugar alcohol that displays high lubricity. Glycerine, mixed with water and several other ingredients, creates a very short-lived lubricious lubricant. Commercially, these lubes are referred to as water-based lubricants.^*

Glycerine is very hydrophilic, meaning interacts well with water. First, it has very high osmolality, which pulls water out of the mucosal tissues of the fist chute. This speeds up the need for reapplication to prevent drag within the hole.

Second, glycerin penetrates skin cells on the hand and arm, which draws moisture from the lubricant into the skin. This loss of moisture creates drag outside the chute around the orifice and rings. It increases the need to apply more lube to eliminate the sensation of insufficient lube application.

Finally, the alcohol component of the glycerine molecule increases the rate of evaporation. Reapplication of more lube or rehydration through misting bottles restores water and returns lost lubricity.

These three characteristics of glycerine lube result in a dry, sticky lube that increases mucosal damage within the fist chute. In general, glycerine-based lubes are not ideal for fisting.

QUICK REFERENCE

• Lubrication Science: Water Dynamics
• Lubrication Science: Chemistry

^*  Note: Water-based is an umbrella term that includes glycerine-based lubes, polysaccharide-based lubes, and PEO-based lubes.

Safety

The results of two studies of glycerine-based lubricants were presented at the International Microbial Conference in 2011. These studies sought to determine how lube affected STI transmission. While the studies did not arrive at a clear conclusion, they indicated that a high contrast in osmolality causes tissue damage inside the fist chute. In lay terms, the amount of sugar and salt in the lube was so great compared to that in the cells of the fist chute that water flows out from the inside the cells to the lube and leaves the cell damaged in the process. ^{[ 1 ] [ 2 ]}

That being said, safety data sheets suggest that glycerine-based lubes are non-toxic and non-irritative when exposure is limited and minimal.

Sanitation and Disposal

Glycerine washes easily with soap and water.

Glycerine lubes typically do not have expiration dates, but many manufacturers suggest discarding any lube older than a year.

Discard full or partially full containers in the waste bin. Recycle empty containers.

Marketing, Value, and Availability

Pricing is reasonable for a bottle of lube, but an hour-long session may require the entire bottle. Lubes can be purchased in the health and wellness section of any pharmacy.

Fisting Considerations and Notes

Glycerine-based lubes can be used for fisting if no other lube is available. Glycerine lubes do not facilitate longer sessions, depth play, or punch play.