With ethnobotanically medicinal plants there's almost always many uses for them:
> Henbane is used in traditional herbal medicine for ailments of the bones, rheumatism, toothache, asthma, cough, nervous diseases, and stomach pain. It might also be used as analgesic, sedative, and narcotic in some cultures
Like I said this isn't that surprising. In ethnobotany if a plant is medicinally important across many cultures like this it's usually a sure bet that there's a ton of interesting secondary metabolites with interesting properties being produced by that plant. These "highly medicinal plants" are actually quite common
Some other examples of highly medicinal plants from PFAF:
Ammi visnaga[^0]
Visnaga is an effective muscle relaxant and has been used for centuries to alleviate the excruciating pain of kidney stones[254]. Modern research has confirmed the validity of this traditional use[254]. Visnagin contains khellin, from which particularly safe pharmaceutical drugs for the treatment of asthma have been made[254]. The seeds are diuretic and lithontripic[46]. They contain a fatty oil that includes the substance 'khellin'. This has been shown to be of benefit in the treatment of asthma[238]. Taken internally, the seeds have a strongly antispasmodic action on the smaller bronchial muscles[254], they also dilate the bronchial, urinary and blood vessels without affecting blood pressure[238]. The affect last for about 6 hours and the plant has practically no side effects[254]. The seeds are used in the treatment of asthma, angina, coronary arteriosclerosis and kidney stones[238]. By relaxing the muscles of the urethra, visnaga reduces the pain caused by trapped kidney stones and helps ease the stone down into the bladder[254]. The seeds are harvested in late summer before they have fully ripened and are dried for later use[254].
Cinchona pubescens[^1]
Red bark has a long history of native use, especially as a treatment for fevers and malaria. Modern research has shown it to be a very effective treatment for fevers, and especially as a treatment and preventative of malaria. The bark contains various alkaloids, particularly quinine and quinidine. Up to 70 - 80% of the total alkaloids contained in the bark are quinine[ 418 ]. The bark is a bitter, astringent, tonic herb that lowers fevers, relaxes spasms, is antimalarial (the alkaloid quinine) and slows the heart (the alkaloid quinidine)[ 238 ]. The bark is made into various preparations, such as tablets, liquid extracts, tinctures and powders[ 238 ]. It is used internally in the treatment of malaria, neuralgia, muscle cramps and cardiac fibrillation[ 238 ]. It is an ingredient in various proprietary cold and influenza remedies[ 238 ]. The liquid extract is useful as a cure for drunkenness[ 418 ]. It is also used as a gargle to treat sore throats[ 238 ]. Care must be taken in the use of this herb since excess can cause a number of side effects including cinchonism, headache, rash, abdominal pain, deafness and blindness[ 238 ]. The herb, especially in the form of the extracted alkaloid quinine, is subject to legal restrictions in some countries[ 238 ].
Hamamelis virginiana[^2]
Witch hazel bark is a traditional herb of the North American Indians who used it to heal wounds, treat tumours, eye problems etc[254]. A very astringent herb, it is commonly used in the West and is widely available from both herbalists and chemists[222]. It is an important ingredient of proprietary eye drops, skin creams, ointments and skin tonics[238]. It is widely used as an external application to bruises, sore muscles, varicose veins, haemorrhoids, sore nipples, inflammations etc[238]. The bark is astringent, haemostatic, sedative and tonic[4, 14, 21, 165, 171, 222]. Tannins in the bark are believed to be responsible for its astringent and haemostatic properties[222]. Bottled witch hazel water is a steam distillate that does not contain the tannins from the shrub[222], this is less effective in its action than a tincture[238]. The bark is used internally in the treatment of diarrhoea, colitis, dysentery, haemorrhoids, vaginal discharge, excessive menstruation, internal bleeding and prolapsed organs[238]. Branches and twigs are harvested for the bark in the spring[238]. An infusion of the leaves is used to reduce inflammations, treat piles, internal haemorrhages and eye inflammations[213]. The leaves are harvested in the summer and can be dried for later use[238]. A homeopathic remedy is made from fresh bark[232]. It is used in the treatment of nosebleeds, piles and varicose veins[232].
Pueraria montana[^3]
The kudzu vine, known as Ge Gen in China, is commonly used in Chinese herbalism, where it is considered to be one of the 50 fundamental herbs[218 ]. Recent research has shown that compounds called 'daidzin' and 'daidzein', which are contained in the roots and the flowers, are a safe and effective method for treating alcohol abuse[238 ]. They work by suppressing the appetite for alcohol, whereas existing treatments interfere with the way the alcohol is metabolised and can cause a build-up of toxins[238 ]. The plant is often used in combination with Chrysanthemum x morifolium in treating alcohol abuse[254 ]. The flowers and the roots are antidote, antiemetic, antipyretic, antispasmodic, demulcent, diaphoretic, digestive, febrifuge, hypoglycaemic and hypotensive[174 , 176 , 218 , 222 , 238 ]. A concoction of the flowers and tubers is used to treat alcoholism, fever, colds, diarrhoea, dysentery, acute intestinal obstruction etc[174 , 176 , 218 , 222 ]. It is useful in the treatment of angina pectoris and migraine[218 ]. The root is frequently used as a remedy for measles, often in combination with Cimicifuga foetida[254 ]. The root contains puerarin. This increases the blood flow to the coronary artery and protects against acute myocardial ischaemia caused by the injection of pituitrin[176 ]. The root can be harvested from the autumn to the spring and is used fresh or dried[238 ]. The flowers are harvested just before they are fully open and are dried for later use[238 ]. The stems are galactagogue and are also applied as a poultice to incipient boils, swellings, sore mouths etc[218 , 222 ]. The seed is used in the treatment of hangover and dysentery[218 , 222 ]. The leaves are styptic[218 ].
Ethnobotany is still the main source of new drug discoveries. Culturally medicinal plants like these are easy to identify and then it's just a matter of isolating the active ingredients and investigating ways to manufacture it or increase its effects. We often think of drugs as being single dimensional or serving a single use-case but I think this is mostly a product of how the modern scientific and legal process works and how much work it takes to approve a drug for a particular use-case.
Imagine you're a big pharma company, are you going to lose market share to a plant? Cheaper to pay a media outlet to start a fear campaign, and hire lobbyist to pass laws against "The dangerous plant" that killed little Toby.
Pharma guarantees exact amounts of the active compounds each single time. Herbal medicine can't, because 5 grams of this plant harvested at shadow is radically different than this other 5 grams of the same species but growing in a colder place, or in a sunnier place or in a short summer year, etc.
Therefore with herbal medicine there is always a risk of overdosing or receiving an useless (too low) dose. The importance of this fact when people deal with such evil things as Scopolamine shouldn't be dismissed.
To be fair most herbal medicinalists tout the decreased potency of an herbal drug as a major benefit. You're usually instructed to, for example, drink some amount of some tea for a month. It might be hard to predict the content of a dose but with most herbs even if you tried to overdose you'd probably just puke out all that plant matter rather than actually die
Every year there's between 10 and 60 total fatalities due to plant and mushroom poisoning annually in the United States. But more than 106,000 persons in the U.S. died from drug-involved overdose in 2021. Obviously many more people take pharmaceutical drugs than take herbal medicines, but I do think that even if you adjusted the numbers to account for that you'd still see a huge difference
The fact is humans have been eating plant matter for millions of years and even though secondary metabolites of plants can be unique, they still often have certain chemical properties that our digestive system can evolve to account for. For example oxalic acid (rhubarb, brown rice, almonds, etc) and saponins (beans, asparagus, spinach, etc) are two very lethal poisons that will kill your cat but that us omnivores have evolved to neutralize and most of us consume daily. In comparison, pharmaceutical drugs are specifically isolated and optimized for potency and it's simply much more difficult for our bodies to adapt to individual chemicals like this (especially if they have novel chemical properties not seen in other parts of nature)
That's true to a large extent with pharmacological drugs, since you have huge variability between people's weights, life style and diets (alcohol use for example). Usually the problem can be mitigated by starting with a safe low dose and adjusting until a benefit is seen in either case.
The profit motive of pharmacological companies is to have repeat customers. So no real incentive to cure.
You can't really dismiss this as a concern, as it's reflected in reality. Americans are some of the most drugged people in the world. The number of drugs Americans are now taking is growing exponentially. Yet this hasn't translated into life expectancy gains at all.
If anything, chances are you will be given the most drugs in the last year of your life. The risk of complications from taking so many drugs, will probably be working against benefit. As you get worse, the doctors will try to increase the dose. A feedback loop of sorts.
Hey, it's not like I'm against modern medicine. It's just it's a little more complicated, when game theory comes into play and individuals/companies have incentives that aren't always aligned with your best interest.
Lots of medicine is not just historically derived from plants but actually manufactured from them - extracting and purifying an active ingredient from plant mass often is cheaper than synthesizing it chemically, so lots of widely used products from 'big pharma' effectively are herb-based.
However, this 'extracting and purifying' step is one that must be done, you don't want to give the patient the whole 'cocktail' of active substances that happen to be in the herb along with the one thing that does have the desireable effect; so skipping that step and using the herb directly often is not appropriate; sure, it can work and have some beneficial effect as it was used historically, but that's something you stop doing once you have the practical ability to do it better by properly extracting the appropriate component.
Because its medical use was for asthma. You could buy solanaceous cigarettes in the US until the 70s or so.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2844275/