Enema play

Enema play is a kink where water or other liquids are administered rectally to a sub for the purposes of producing intense sensations of cramping and fullness, and can be related to bowel control play.

Enema play

Health risk	Moderate
Legal risk	Mild

Methods

Gravity enemas

A common approach to administering enemas is to fill a reservoir bag with liquid connected via tubing to the sub's rectum. Flow valves inline with the tubing are often used to regulate the rate at which the enema is administered to the sub. The bag can be passively raised to generate a pressure gradient to drive in the liquid via hydrostatic pressure.

Gravity enemas are generally a lower risk technique for enema administration, as the height of the bag establishes the maximum amount of pressure that can be generated, though it is still possible to generate dangerously high pressures if the bag is elevated too much.

Electrolyte additives

For large volume enemas that will be retained for a considerable amount of time, electrolytes should be added to the water to minimize risks and improve comfort. Most optimally, a fully balanced solution containing multiple electrolytes at appropriate levels such as normosol, plasmalyte, or lactated ringer's would be used. If these specialized solutions are unavailable, at minimum add 8 grams of table salt per liter of water prepared, which will create an enema solution that has a reasonably balanced osmolarity (280 mOsm/L) and sodium level (140 mEq/L).

Risks

Colonic pressure injury

The administration of an enema is made possible by a pressure gradient between the water in the enema reservoir and the intraabdominal pressure in the subject. The magnitude of this pressure gradient will affect the flow rate of the enema which can affect the sub's experience in either positive or negative ways depending on the goals of the scene. The pressure gradient also considerably affects the risk of injury during an enema.

Intraluminal colonic pressures exceeding 80 mmHg are considered to carry meaningful risk of colonic perforation in people with healthy intestines. In people with pre-existing tissue damage of the colon, the threshold may be closer to 50 mmHg.

Gravity enemas

For gravity enemas, the height of the bag will be the sole factor that determines the amount of pressure generated in the colon. The pressure that will be generated can be calculated using the equation for hydrostatic pressure: $P=\rho gh$ (ρ is the density of the fluid, g is the acceleration due to gravity, and h is the vertical height difference between the top of the fluid of the bag and the sub's body). Assuming the fluid of the enema is similar to water and typical gravity conditions, the pressure produced in the colon (in mmHg) can be calculated using either of these formulas:

• $P=1.868*h_{inches}$
• $P=0.735*h_{centimeters}$

If a large volume enema is going to be administered via free flow and the rate not slowed or stopped based upon the sub's response, it is generally recommended to limit the height of the bag such that the top of the water level is no more than 24 inches or 60 cm (corresponding to a colonic pressure of above the sub to minimize the risk of injury).

Pressurized enemas

Enemas which are administered via a device that generates positive pressure independent of hydrostatic pressure can lead to increased risk depending on the design and safety constraints of the device.

Electrolyte abnormalities

The colon readily absorbs water and electrolytes into the bloodstream. If a large-volume enema is administered and retained for a considerable amount of time and the fluid used is not adjusted to match the electrolyte levels of the blood, acute electrolyte disturbances can occur which can be dangerous.

Electrolyte issues are most commonly encountered when tap water is used, which contains functionally no electrolytes and can most notably lead to hyponatremia, hypokalemia, and hypocalcemia which can be life-threatening if severe and untreated. Additionally, the hypotonic nature of tap water can cause considerably more discomfort and irritation of the colonic mucosa than if a balanced fluid is used. Electrolytes can be added to tap water to recreate a balance that matches electrolyte levels in the body, leading to both a safer and more comfortable experience for the sub.

Intoxicating additives

Many intoxicating substances can also be absorbed rectally and can be added to enemas to produce additional effects in the sub. Caution must be taken and specific research should be done for each substance being considered, as some substances are considerably more or less potent when absorbed rectally than via other routes.

It is also possible to administer dangerously large doses of intoxicating substances via enemas, given the large volumes and rapid flow rates involved. Additionally, some substances can be directly caustic to the rectal and colonic mucosa if administered in high concentrations. Alcohol in particular has been reported to have caused multiple fatalities and episodes of colitis from administration in enemas.

Risk mitigation

• Do not raise the bag for large-volume free-flowing gravity enemas more than 2 feet above the sub if it will not be possible or desirable to reduce or cease the flow of the enema based upon the sub's sensations
• If higher pressures are used, it is very important to be responsive to the sensations of the sub and limit additional inflow if the subject experiences severe cramping
• Use a liquid that contains the right amount of electrolytes
  • Most ideal to use "balanced" solutions such as normosol, plasmalyte, or lactated ringer's
  • At minimum, add 8 grams of table salt per liter of water prepared

Known incidents

Medical case reports

• An unusual form of fatal ethanol intoxication (2005)
• Charges dismissed in sherry enema death (2007)
• Self-administered ethanol enema causing accidental death (2014)
• Self-administered alcohol enema causing chemical proctocolitis (2019)