Integrative medicine is the practice of supplementing medicine which works with pseudomedicine that doesn't. The general justification is that patients will like it more.
The purpose is to gain greater acceptance, and hopefully funding, for pseudomedicine - a stalking horse for woo.
The fatuity of this idea can be readily understood by considering the effect of "integrating" apple pie with cow pie. Does this make the apple pie taste better or worse? You decide. No, really, you decide, I am not interested in a blind tasting.
Peddlers of integrative medicine use the generic woo ploys of asserting that their bullshit is "holistic" (in a way that medicine supposedly is not, since doctors routinely treat melanoma patients with band-aid to cover their bleeding moles, for example, rather than actually looking at medical history), and claiming that sound scientifically supportable interventions such as diet, exercise and physiotherapy are "integrative" and thereby seeking halo effect from valid treatments to polish their turds.
 See also
- CAM, its immeditiate predecessor
- Alternative medicine, its grandfather
- Quackery, its great grandfather