Definition
Adjuvant herbs are those herbs which enhance body's Immune response to an antigen.
The word may be used as an adjective. For example 'Adjuvant therapy'. A treatment given to a cancer patient in addition to the primary therapy, to suppress secondary tumor formation.
Adjuvants may be Immunological. They help vaccines to stimulate the Immune system's response to an antigen. By themselves they do not build immunity.
They may synergize the power of the antigen by irritating the immune system to increase its response.
The body develops an antitoxin to the bacteria's toxins, not to the Adjuvant. The Adjuvant acts as a catalyst.