Although different substances induce different effects regardless of their appropriate dosage, the intensity of the experience they are likely to induce can be broken down into five separate categories.
A threshold dose is the dose at which the characteristic effects of the substance first become apparent. It is distinctly beyond that of placebo effect, but can be ignored with some effort when one directs their focus towards the external environment. Users may perceive a vague sense of "something" or nervous anticipatory energy occurring at this level.
A light dose will cause effects which are noticeable and clearly distinct from sobriety, but remain in the background of the user's perception. The effects remain possible to ignore by increasing the focus one directs towards other things when performing complex tasks. The user may have to pay particular attention to the effects of the drug for them to be recognizable, or they may be slightly noticeable but will not insist upon the user's attention.
Within this range, not only are the effects and the nature of a drug's action quite clear and distinct, but ignoring its action becomes difficult. The user will generally be able to partake in regular behaviors and remain functional and communicable. The effects can be allowed a predominant role or they may be repressed and made secondary to other chosen activities.
A strong dose renders its subject as mostly incapable of functioning or interacting normally, or thinking in a sober manner. The effects of the drug are clear, but at this level they are no longer ignorable and the user is engaged entirely in the experience.
At heavy doses, the user has reached the upper limit of what this compound is capable of producing in terms of perceivable psychoactive effects. Depending on the substance consumed, the user may be rendered incapable of functioning on any basic level, experience extremely uncomfortable side effects, or hit a ceiling dose with diminishing returns.
An overdose is a quantity greater than recommended, intended or generally practiced, with the possibility of the dose resulting in death or serious injury. Immediate professional medical advice should always be sought when a user has taken a dose greater than or equal to this, although tolerance may allow experienced users' bodies to survive such doses unharmed. It should be noted that doses below this level may also be harmful in some cases.
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