I don't think that there's a proponent of science-based medicine alive who doesn't understand that plant compounds are important in medicine and it is important to research them. We *DO* get a lot of medicine from plants.
But "medicine from plants" and "herbalism" are not the same.
The example that most people like to bring up is aspirin and willow bark tea. You can use willow bark as a painkiller, you can collect your own and brew it up when you've got a headache.
What you can't do is control the dose. You can't do this for a number of reasons, including having little control over the conditions the tree grew in and variations in preparation technique. If you're measuring very exactly you can control for some of these things, but even if you were in charge of the willow tree you collected the bark from it's not going to be the same at different places on the trunk or in different seasons.
That's not a huge deal if you're using aspirin for a headache, it can be a much bigger deal if you're using aspirin as a bloodthinner.
And the example that people LIKE to use is aspirin because it *isn't* a big deal. The example they *don't* like to use is foxglove (digitalis, which produced digitoxin, which can be used to treat heart failure) because that's a medicine from a plant that you can't fuck around with using herbalism, it needs extremely careful extraction and preparation because if it's done wrong it'll just straight kill you.
And then you get into herbal treatments that are generally safe and largely not harmful even if they may not do anything, and it can feel totally reasonable to recommend red raspberry leaf tea to a friend who is having cramps. As long as that friend isn't diabetic because red raspberry leaf interacts with insulin. And as long as your friend isn't on an anticoagulant because red raspberry leaf can ALSO act as an anticoagulant.
And those are just examples of what can happen if you know you are actually getting the plant that you think that you are getting and that it is unadulterated with fillers and uncontaminated with anything else and is properly prepared (or is prepared the same way as the last batch you bought and so it can be dosed the same way).
There are two ways that Kava Kava can be prepared; do you know which of those two ways is associated with more deaths and liver transplants? Do you know not to take Kava if you have a history of liver issues or if you are on antidepressants? (ctrl+f for "Hema Ketha" for the study from that overview that goes in depth on that; for whatever reason you can read the whole article in the overview but if you click on the link you only get the abstract)
Are you attempting to take therapeutic doses of turmeric? There's some evidence that it can help relieve joint pain. However you need to take really, really high doses because the medicinal compound in turmeric has low bioavailability. And because you're taking high doses you may be swapping out the risks of NSAIDs for the risk of lead poisoning, because it is unfortunately very common for turmeric to be contaminated with lead.
One of my big, big problems with CAM - including herbalism - is that people turn to it because they think it is safer than "allopathic" medicine. They think "it's better to drink raspberry leaf tea than it is to take midol because midol is full of chemicals and raspberry leaf tea is just tea." But midol doesn't interact with insulin, and most people are *aware* they're taking a blood thinner when they take NSAIDs.
There's this tea shop I go to that has maybe a hundred different kinds of herbal teas, some of which are clearly supposed to be medicinal, but the one that always stands out to me is the St. John's Wort tea that has "NOT FOR PREGNANT" on the label. It's good that they're recommending that pregnant people don't select that tea, but that tea is also not for people on antidepressants, triptans, birth control, warfarin, stantins, protease inhibitors, or people who have had solid organ transplants.
But it's just tea. And what could just tea do, right?
(It could make your anti-rejection meds so weak that it kills you. That's what just tea can do. But maybe one cup of older tea, or one cup that is more leaf than flower, or one cup that wasn't steeped as long doesn't hurt, so you drink it and you think it's fine, it's not a problem, and it isn't a problem until it is but you don't know the difference between one cup of tea and the next because this shit is impossible to dose)
This is also why I'm extremely leery of the "you can try CAM as long as you are using it alongside your doctor's care and you do what the doctors say" thing because that is relying on:
People reporting every supplement, tincture, tea, etc. that they are taking to their doctors (which they often don't do because what's the big deal it's green tea extract and billions of people drink green tea every day)
The ingredients in the supplements being exactly and ONLY what is on the label (which is a long shot - it seems like every three years there's a study or a report that finds that supplements - usually in the US but also around the world - don't contain what they are supposed to and often contain stuff they are not supposed to)
Doctors being aware of all of these possible interactions (which is a stretch; pharmacists are likely to have a better handle on it but even then, there are all kinds of supplements being labeled all kinds of things all the time; medical woo scammers LOVE to rebrand their supplements)
So long story short I'm not particularly bothered if you try herbalism on yourself after looking into things that you think will help you. I do have a problem with people who *recommend* herbal treatments without A) a full medical background understanding of the person they recommend the treatment to and B) comprehensive knowledge of whether the thing that you're recommending will interact with any medications they might be taking or exacerbate any conditions that they might have and C) some kind of accountability mechanism in place - like a malpractice suit or the loss of license - like a doctor might if they prescribed a medication that was dangerous to their patient.
Because that's the other infuriating thing - CAM practitioners often aren't held to the same standards as medical professionals. Patients who trust CAM practitioners often think of them like doctors, but they don't have the same protection from CAM practitioners like they would from doctors. If your herbalist tells you to treat your cancer with apricot pits or black salve - even if that's in addition to chemotherapy - it could end up seriously injuring you and they're not committing malpractice because there's no legal standard for their practice. Nobody can remove their license because there's no such thing as an herbalist license, so whatever harm they did to you can be done to other people after you with no professional consequences.
I have pretty much limitless tolerance for things that people want to do to themselves. If you want to take valerian because you think it helps you sleep (in spite of essentially no evidence that it does so and more adverse reactions among natural sleep aids than things like camomile - which also has no evidence that it's an effective sleep aid) I don't care, just make sure to check for drug interactions first.
If you want to replace your elderly parent's NSAID painkillers with clove oil, fuck you.
