Active & Passive Reaction

Active and passive reaction describe the two ways the living organism answers a medicinal or disease-producing stimulus. When a remedy first acts, the vital force submits to its impression and, for a time, allows the change — this is the passive reaction. The vital force then rouses itself and replies with its own energy, either raising the opposite state or driving the organism back toward health — the active reaction, or counteraction. Hahnemann built the distinction into the Organon as the twin phases of every drug action: the primary action of the medicine, to which the organism yields, and the secondary action of the vital force, by which it recovers.

In Practice

The two phases are easiest to watch in the provings gathered in the materia medica. Strong coffee, taken by a healthy person, first produces over-excitement, racing thoughts and wakefulness — the primary action, met by a passive reaction. Once that impression fades, the vital force answers actively with the opposite state: heaviness, drowsiness and dullness. Opium runs the same course in reverse, beginning in stupor and heavy sleep and ending in sleeplessness and over-sensitivity.

This rhythm is the engine of cure by similars. The remedy's primary action is a mild, artificial disturbance slightly stronger than the natural illness; the vital force, provoked into an active counter-reaction against the remedy, carries the weaker natural disease away with it. We are not medicating the tissue directly so much as borrowing the organism's own reactive power and pointing it at the disorder.

The distinction also sharpens ordinary case reading. The keynotes that mark a remedy are drawn mostly from its primary action, while the alternating or seemingly opposite symptoms in the same picture belong to the secondary reaction — one reason a single remedy can cover both a complaint and its apparent contrary. It refines the reading of a modality as well: a symptom briefly better and then decidedly worse, or an early aggravation that gives way to lasting relief, often marks primary action passing into secondary reaction rather than a simple worse-from-this, better-from-that.

Historical Context

Hahnemann set out the principle in aphorisms §63 to §65 of the Organon of Medicine. In the primary action, he wrote, the vital force appears passive, compelled to permit the impression of the artificial disease-agent; in the after-action it appears active, either raising the exact opposite condition — as coffee's excitement yields to drowsiness — or, where no opposite exists, exerting its energy to extinguish the disturbance and re-establish health. Later writers on homeopathic philosophy, among them Stuart Close and H. A. Roberts, carried the idea into prognosis: a vital force able to mount a vigorous active reaction points toward recovery, while one so depleted that it can only submit passively signals a poorer outlook.

Related Terms

• Keynote — the most characteristic symptoms of a remedy, drawn chiefly from its primary action
• Modality — a circumstance that makes a symptom better or worse, read more precisely in the light of action and reaction
• Materia Medica — the record of proving symptoms in which both primary and secondary states are preserved

Learn More

• Materia Medica — how proving symptoms, primary and secondary alike, are compiled and consulted at the bedside