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Root medicine required careful dosage consideration. The concentration of active compounds in roots meant that dosing errors could be serious—too little produced no effect, wasting valuable medicine, while too much could cause side effects ranging from uncomfortable to fatal. The experienced healer learned proper dosage through apprenticeship, through observing results, through understanding that different individuals required different amounts, that body size, age, overall health all affected optimal dose.
Children received proportionally smaller doses than adults, the calculation based on weight and age, the adjustment preventing overdose in smaller bodies that could not tolerate adult dosages. Elderly patients sometimes received reduced doses, their kidneys and livers processing compounds less efficiently, requiring lower intake to achieve desired effects without causing accumulation that would lead to toxicity.
Some roots had narrow therapeutic windows—the difference between effective dose and toxic dose was small, requiring precise measurement, careful monitoring, willingness to reduce dosage at first signs of adverse effects. Mandrake epitomized this problem—effective pain relief dose was close enough to toxic dose that errors were dangerous, making mandrake prescription restricted to experienced healers who understood the risks and possessed skill to navigate them successfully.
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