No, @MuddyBoots, @Crazy Hitch @amandalouise, it is not exactly that. True, it is used by people such as the person who essentially attacked Moose to mean evidence-based approach (in a derogatory sense), but it does not mean that or at least it did not mean that historically.

Allopathic meant the opposite of homeopathic. So it is one pole in the artificial dichotomy between allopathy and homeopathy. Homeopathy is treating with the "same" (homeo), and allopathy is treating with the "opposite" (allo).

Modern evidence-based medicine is far, far wider than allopathy. It also includes preventive care, which may not even involve any treatment, with the "opposite" OR with the "same". And some vaccinations function as treating with the same, and yet they are evidence-based. So there is no clear demarcation line anyway. And, say, talk therapy is not treating with the same, nor is it treating with the opposite - it is orthogonal to the supposed axis where same and opposite are the opposite poles. Unless you consider exposure therapy for anxiety part of talk therapy, and if you do, then such talk therapy is homeopathy, because it is treating with the same – like some older vaccinations, it is exposing the patient to what triggers the illness in small, but increasing doses, until the patient overcomes the anxiety. If the person is afraid of social situations, the therapy prescribes social situations. It is treating with the same. In literal terms, it is homeopathy and not allopathy.

Actual homeopathy does not actually treat with the "same" because it does not treat at all: the multiple dilutions involved in preparing homeopathic "remedies" render the resultant product devoid of any active substance. If you use homeopathy, then, unless you believe that water can possess "memory", you are taking a sugar pill, a placebo. The only benefit can be attributed to the placebo effect, which does exist. I have recently heard a good analogy: we are more likely to be drinking Hitler's urine than finding any active substance in homeopathic "remedies". This is because the number of dilutions necessary to obtain such a remedy is higher than the number of dilutions it would have taken for Hitler's urine to reach our municipal water supply. Of course, this makes homeopathic remedies highly profitable, because the profit margin is insane (the main cost is advertising, distribution, and managing the supply chain and not producing the stuff).

Homeopathy caused the evidence-based medicine to develop. The first experiments with controls that gave rise to modern evidence-based medicine were performed in the 19th century specifically to disprove homeopathic claims. And they did! But homeopathy survived and continues to survive, being the ultimate form of quackery. Still, we should be thankful for homeopathy because who knows, maybe evidence-based approach to medicine would have taken many more decades to be born if not for homeopathy. That is homeopathy's main contribution to humanity, and it is, hands down, a very important contribution. A key contribution. But that is all.

Since then, allopathy has become a swear word used by people who would use any type of snake oil as long as it is "alternative". Which by itself would be innocuous enough, as people should be free to experiment on their own bodies. But when such people experiment on their children or demented elders who cannot consent, or when they undermine the efforts of genuinely ill people, such as Moose, to obtain genuinely effective treatments for their real diseases, it is rather disgusting. It has become a weaponized term.

To sum up, allopathy has never been defined carefully enough to begin with, and now it is used to demean other people, the way this person demeaned Moose.