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The forest herbalist necessarily understood poisons alongside medicines. Many medicinal plants were toxic in excess, their therapeutic effects indistinguishable from toxic effects at higher doses. The healer who prescribed digitalis (foxglove) for heart conditions needed to know that slightly too much stopped the heart rather than regulating it. The practitioner using belladonna (deadly nightshade) for pain relief understood that overdose caused delirium, convulsions, death.
This poison knowledge created dual reputation for forest healers. They were valued for their ability to cure but feared for their ability to kill, the same knowledge allowing both applications. Some healers explicitly avoided poison knowledge, restricting their practice to entirely safe remedies, accepting limited effectiveness to avoid the social complications that came with being known as someone who could prepare lethal preparations. Others embraced the full scope of forest pharmacy, understanding that the most effective medicines were often those closest to poisons, that healing sometimes required accepting risk.
The legal implications were significant. The healer whose patient died after treatment could face accusations of deliberate poisoning, the fine line between medicine and murder impossible to definitively establish when cause of death could be either disease or overdose. This created pressure for healers to be conservative, to use only well-established remedies at known-safe doses, to avoid experimentation that might prove effective but might also result in disaster that would be interpreted as murder.
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