You are largely right on western medicine, it is holistic as far as the scientific evidence is relevant. That means if there is no unbiased experiment on the 20 year effects of some effect of some drug then there is no science behind it and therefore no knowledge and no treatment. Causative treatments are established to a degree as close to absolute as possible using the scientific method. However, because scientific experiments are biased towards things that are easily observable and measurable, treatments are also biased in this direction.
In other words it is very hard to run an experiment on the 10 year side effects of some drug therefore there aren't much treatments of this nature among western medicine.
Eastern medicine is the opposite. It has no basis in science in the sense that none of it's tenants were established in scientific measurement and observation. More it's adhoc trial, error, a lot of bias and a lot of fraud. This kind of treatment can definitely be more "holistic" but this holisticness is based off vague and anecdotal evidence and is very inexact. Some eastern medicine may work and some may not and you may be being lied to.
In fact, the logical theory behind eastern medicine is utter crap. The logic talks about chi flows going through your body of both hot and cold and the logic is to eat medicine to help control balance in the chi flows. These chi flows are a fantasmic concept not observable by scientific experiment.
This does not mean eastern medicine doesn't work. THe reasoning might be off but the effectiveness of the medicine may still be valid because cultural selection would have virtually eliminated this field if it did not actually aid with survival in some form or manner. Just know that every time you ingest some medicine based of of eastern philosophy know that you are making a gamble on evidence that is anecdotal and possibly placebo induced or even fraudulent.