The term “Immunity” refers to the resistance exhibited by the host towards injury caused by microorganisms and their products. We can say it as “Susceptibility”. Susceptibility means the general quality or capability of the living organism to receiving impressions and the power to react to stimuli. It is one of the fundamental attributes of life. All functions depends upon it, all vital processes both physiological and pathological. Digestion, assimilation, nutrition repair, secretion, excretion, metabolism and catabolism as well as all disease processes arising from infection or contagious depends on the power of the organism to react to the specific stimuli.

    Susceptibility as a state may be increased, diminished or destroyed. The morbid susceptibility may be regarded as state of lowered resistance. Homoeopathic medicines improve innate or native immunity. It is the resistance to infections, which an individual possesses by virtue of his genetic and constitutional make up. It also stimulates the phagocytic cells, which ingest and destroy the microorganism.

    Artificial active immunity is the resistance induced by the medicines.. The potentized Homoeopathic medicines are capable enough to be used for Homoeopathic immunization purposes. In this respect the Nosodes that contains the “dynamis” of the organism responsible for a specific disease are used extensively to immune a person against that specific disease.

    Other than Nosodes any Homoeopathic medicine, which is capable of producing similar symptoms to that of the disease intended to be prevented, can be administered for the purpose of immunization. The reason being that the medicine having similar symptoms produces similar antibodies (stronger) in the system and in the process prevents the action of the similar disease antigen (weaker). This explanation truly follows the phenomenon as observed by Dr.Hahnemann regarding meeting of two similar diseases in the living body.

    The duration of the action of immunity produced after administration of the potentised Homoeopathic medicine varies from person to person, as no two individuals are alike on this earth. It depends on the general health of the patient & on some environmental factors.

    To immunize a person Homoeopathically it has been advised to use medium potencies of the medicine prepared in centesimal scale. It is to be given in repeated doses and the dose should be stopped immediately when some reaction in the form of malaise, lassitude etc are observed in the person. The medicine can also be repeated in a different way where each subsequent dose would be a little stronger than the previous dose, which can be obtained by succussion.

    The individuals can be immunized with a constitutional remedy or a remedy selected from particular nosode.