From all the possible substances that can be input into a biochemical system, the selection of a sub-group of chemicals and labelling them as 'drugs' usually depends upon inclusion criteria that are vague and disputed. Because of the range of conflicting vested interests that are inevitably involved, a ruthless pragmatism needs to be adopted in all behaviours which are concerned with those substances that have been classified as 'drugs' by some self-interest or other.

A practical working definition would be to classify something as a 'drug' if a small measurable dose of it causes a measurable non-fatal perturbation in the biochemical system. Thus unmeasurable homoeopathic administrations are not 'drugs' but 'placebos', large fatal doses are called 'poisons', and bulk ingestions are called 'foods'... roughly speaking. There is an element of the chaotic in the essence of a drug. Quite a small amount can have significant consequences and unpredictable side-effects on all the biological systems striving to sustain the core functions of nutrition, sensory perception, sex and thought. The perturbations introduced into the biological system will range in effect from the 'healthy' to the 'unhealthy', in that some will have a beneficial influence and others not. Determining where a substance classified as a drug fits on this spectrum of evaluation is an ongoing human preoccupation.

Whilst a lot of testing is done on and by humans themselves... like drinking brewed beverages, smoking diverse dried herbs, and chewing miscellaneous nuts and seeds, never-the-less the recent inclination has been to altruistically give other species the first opportunity. Some disposable animals are are more suitable and available than others. Muridae for example, are one of the favoured species for the exercise of trialling any synthetic or extracted substances that may be potential items for human pharmacies. When one such amplified effect is perceived as being beneficial... it is not often clear to whom... human trials are initiated. Unfortunately, the feedback sequence established usually induces the widespread assumption that if 'some' appears to be good, then 'more' will be better, and 'abuse' will be best.

Any system is destroyed by destabilizing it beyond its capacity to restore balance, so that introducing a poisonous excess into a biochemical system is to provoke catastrophic failure. The deliberate administration of any substance into a biochemical system, without an appreciation of the scope of variation that the system can compensate for, is to invite disaster. The drug itself may not be sufficient to induce a fatal perturbation, but the disruption of control systems induces extreme vulnerability. The deliberate induction of a state of vulnerability, for no medical purpose, is direct evidence for biological stupidity.

Drug promotion and attempts at controls have difficulty in avoiding being both hypocritical and self-serving. Education is often suggested a means of providing a more realistic perspective, but even the most well thought out and effective programs can only provide a small compensation for the widespread and self-serving systems of advertising and distribution of drugs. Whilst many are ostensibly to alleviate or prevent actual or invented conditions, or to supposedly enhance various capacities, they are invariably also a particularly profitable niche for self-interest. Participating in this culture, willingly or otherwise, is an increasing source of apprehension, as discriminating between the well-meaning and sinister becomes confused, the limits of trust are severely tested, and the sophistications of deception become increasingly elaborate. Accepting the stark reality that drugs and their misuse is an ineradicable aspect of human society, it is arguable that the pragmatic action of removing all enforcement control attempts would result in no greater social disarray than is evident with them. A different group of individuals would become wealthy of course, but there would be fewer of them, and with social approval they wouldn't need to resort to violence and armaments. The complexities of a drug culture, with health and medicine confused with recreation and intimidation, makes the humorous perspective more demanding. There is however some comic relief in observing the sincere protestations of certain individuals, who persuade themselves that they are more intelligent after pushing mushroom portions up their nasal passages.