A surge of strength, increased performance, improved mood and quality of sleep, a feeling of being rejuvenated, and much more comes from cleansing the body from the inside (internal spa). Compared to other methods and means intended for this purpose, Matkevich lavage removes harmful substances from the body faster and more reliably. Surprising, but true: Matkevich lavage cleanses not only the intestines, but also other organs, including blood. This means that you do not need to swallow dietary supplements for months, brew cleansing herbs and tea, be tortured by tube insertion. Matkevich lavage is a one-of-a-kind method of cleansing the body from the inside, since its effectiveness and safety have been studied scientifically, and tested for several years in leading medical institutions. It is patented, officially approved for use by Russian healthcare regulator, Roszdravnadzor, and received the Moscow City Hall Award. The results of the work are presented in more than 90 scientific publications, and reported at dozens of conferences and congresses in Russia and abroad.