Body load

Body load is a term employed by users of psychoactive drugs, and especially users of psychedelics, to describe specific tactile sensations brought on by drug use. Generally, body load is an unpleasant physical sensation that is difficult to describe either in terms of other sensations or in its specific location. (It is usually an "all-over" or "everywhere" sensation, except when accompanied by nausea, as noted below.) Body load is, for most purposes, synonymous with the term "body buzz" (and sometimes "buzzing" in general, when the latter term was used to describe feelings accompanying the onset of effects of such drugs as LSD-25 and psilocin; this usage was more common during the 1960s, however, and a "buzz" now usually means a feeling of light intoxication.)

Attempts at clearer description of the sensation often refer to feelings of restlessness, "internal vibration", and tension, and many people also report experiencing nausea along with, or as a part of, body load. In contrast, many drug users, and particularly users of entactogens like MDMA or of certain particular synthetic phenethylamines (most notably the popular 2C-B) and tryptamines, also often report a "body high" or "body rush", which is similar to body load in many respects but is virtually always considered pleasant.

Users also report that different drugs cause different body load sensations which vary in pleasantness, intensity, duration, et cetera. For example, 2C-B has been described by many users as having pleasant, aphrodisiac-like properties, while 2C-E, 2C-T-2, and several other phenethylamines and tryptamines are reported to cause unpleasant physical sensations regularly; users of these drugs ignore or disengage themselves from these sensations in order to focus on other effects, such as visual patterning, aural distortions, et cetera.

The causes of the subjective experience of body load are unknown. However, one proposed mechanism is the stimulation of serotonergic receptors, particularly those involved in tactile sensation and, equally importantly in many cases where nausea is experienced, those located along the lining of the digestive tract. Serotonin is heavily involved in appetite control, and overstimulation of serotonergic receptors has been shown to cause nausea in, for example, overdoses of SSRIs or MDMA. Since most psychedelics which can cause bodyload are partial serotonin agonists which work by mimicking the structure of serotonin to varying degrees, this connection is likely.