Enderlein developed Isopathic Therapy with its specific biological remedies for all nonspecific, general symptoms that pertain to the Endobiosis Complex, based on the knowledge of the mutability of forms and the fact of the biological, and essential for life symbiosis between the mammal organism and the Endobiont. This unique perspective, at that time, distinguishes Enderlein as a pioneer of a modern, ecological world-view and puts monomorphism, which is still being taught, in question.

In his Bacteria Cyclogeny, Enderlein describes the development of the two mold fungi species Aspergillus nigervan Tieghem (SA 4-20) and Mucor racemosusFresen (SA 4-11), beginning from the primitive phases as tiniest colloidal albuminoid particles, via the bacterial phase, up to the fungal stage.

Both fungal species, which are likely obtained transplacentally, can occur as Endobionts in all their developmental stages within mammal bodies. Although their occurrence may be more or less frequent, they are to be seen as the cause of numerous ailments. The tubercular and paratubercular diseases, caused by pathogenic Aspergillusstages, do not occur quite as frequently as the disease processes more frequently caused by pathogenic Mucorphases arising from the Mucor symbiosis. The presence of the Endobiont in mammal organisms has been termed Endobiosis by Enderlein since 1946. By this are meant the apathogenic, low valanced phases of the Mucor racemosusFresen (SA 4-11) (Protits, Symprotits, Chondrits, Fibrin). Fibrin is the highest developmental form of the Chondrit, before the Endobiont changes from the primitive phase into the bacterial phase (analogously to Siphonospora polymorphav. Brehmer). In these lower valences, the symbiont supports the metabolism of the host organism, thus strengthening the defense. The higher the Endobiont rises in its developmental series, the more it increases in toxicity. The upward development of the Endobiont via the Chondrit form and higher is the cause for the endobiontic diseases, up to the death of the host organism. In the course of this process, the Endobiont is most likely partaking in the development of tumors. In the stages of precancerosis, one finds higher valenced Endobionts in the blood. According to Devrient, the cancer problem cannot be solved without regard to blood parasitism and polymorphism of the microorganisms. For Enderlein, "cancer is for the host organism a fermentation and decomposition condition, forced upon it by a parasitic fungus and its developmental forms."

Because the Endobiont devours protein greedily, its upward development and the Endobiosis or congestion resulting from it are especially co-created through improper nutrition. Among these diseases belong vascular changes, pathological coagulatory processes, geloses, rheumatism, arthritis, spondylosis, tonsillitis, lymphogranulomatosis, diabetes, gout, tumors of every type (even those that are benign and their prestages), anemia, leukemia, cerebral sclerosis and paralyses.

The restriction of protein intake causes the return to lower phases, which then leave the body via the organs of excretion.

The Isopathic Preparations of the Fungal Phase

Another possibility for the breakdown of higher forms into lower stages is the exogenous supply of the so-called Chondritins in the quoted isopathic therapy. According to Enderlein, Chondritins are apathogenic, low developmental stages of diverse fungi, which can be either of a specific nature, as in the Mucor racemosusFresen (SA 4-11) and Aspergillus nigervon Tieghem (SA 4-20), or of an unspecific nature such as in Penicillium chrysogenum(SA 4-30) and Penicillium glabrum(SA 4-31). The specific Chondritins metabolize the virulent, parasitic microorganisms by copulation, thereby initiating their breakdown. The nonspecific Chondritins act as stimulating irritants by supporting the defensive capacity of the human organism through absorbing the ferments of foreign microbes.

Chondritins from diverse mold fungi and yeasts are available for application, for example, in the following preparations:

ALBICANSAN, Candida albicans

EXMYKEHL, Candida albicans, Candida parapsilosis, Penicillium roquefortii

FOMEPIKEHL, Fomitopsis pinicola

FORTAKEHL, Penicillium roquefortii

LARIFIKEHL, Laricifomes officinalis

MUCEDOKEHL, Mucor mucedo

MUCOKEHL, Mucor racemosus

NIGERSAN, Aspergillus niger

NOTAKEHL, Penicillium chrysogenum

PEFRAKEHL, Candida parapsilosis

PINIKEHL, Fomitopsis pinicola

QUENTAKEHL, Penicillium glabrum

RUBERKEHL, Aspergillus ruber

SANKOMBI, Mucor racemosus, Aspergillus niger

SANORYZAE, Aspergillus oryzae

STOLONIKEHL, Penicillium stoloniferum

These remedies have been developed partly by Enderlein himself and partly on the basis of his most valuable research. They act in the way of isopathy; that means, they are not directed against the disease or its symptoms, but they support the body's own capabilities for regeneration, whereby genuine healing processes become possible. Isopathic Therapy nonviolently normalizes the symbiontic equilibrium between the Endobiont and its host organism on a basis of species-identical organisms.

In addition, through the administration of the so-called anti-Chondritins MUCOKEHL Atox(Excretion) and NIGERSAN Atox(Excretion), antibodies for the fungal Chondritins, both their breakdown and their elimination through the urinary paths, the bronchi, the skin, and especially the intestine, can be accelerated.

The preparations FOMEPIKEHL, LARIFIKEHL, PINIKEHL, RUBERKEHL, SANORYZAE and STOLONIKEHL  represent fungal preparations, which have had traditional healing reputations in folk medicine; these preparations are produced as isopathic substances based on the knowledge of Prof. Dr. Enderlein.