Both a Poisonous and Medicinal Plant: Wildflower Debut 139 Greater Celandine

There was a cute yellow flower displayed in the bakery. Apparently, the owner's grandchild picked it along the railroad tracks.
Hmm? That's a cute flower. Let's see, what is this flower? Since I'm currently on my 'wildflower debut' journey, I'm identifying it 😆
It's a wildflower I'm seeing for the first time. 🤷‍♀️ I don't know it.
Compared to the cute flowers, the leaves look like chrysanthemum leaves.
So,
it's time for the 'Michikusa-bu' (Wild Plant Club) to step in.
They said it's Greater Celandine (Kusanō). And here is the reply I got:
'Since Greater Celandine is poisonous, it's fine to display it, but please tell them to be careful about washing their hands and handling the water in the vase.' 'As long as you are careful with the sap, it's fine.'

When I told the bakery owner that, they said, 'Oh, is that so? I was wondering why the glass bottle kept turning yellow no matter how many times I changed the water.'

The sap is quite potent.

When I looked up Greater Celandine, I found information on Wikipedia, EVERGREEN, and other sources.

In 'Three Collections of Medicinal Plants for Home Use' (by Junpei Sato), which I use as a reference book for researching medicinal plants, Greater Celandine is listed as both a medicinal plant and a poisonous plant.

The article is interesting, so here is an excerpt from the Greater Celandine section.

🔷 Crude drug name: Bai Qu Cai (Greater Celandine) Properties: Unknown Taste: Bitter
Papaveraceae, Chelidonium genus
Efficacy: Warts, ringworm, skin ulcers, boils, antispasmodic, analgesic
The aerial parts are harvested and dried, referred to as 'Bai Qu Cai,' and used as medicine.

The yellow sap that oozes out when the living plant is damaged tastes bitter and causes redness, swelling, and rashes if it touches the skin.

Sap components

It contains alkaloids such as chelidonine, coptisine, homochelidonine, protopine, and allocryptopine.

Chelidonine alkaloids have effects similar to opium alkaloids, but it is said they do not cause side effects like dizziness, lethargy, or constipation as opium alkaloids do.
Therefore, utilizing its analgesic and peripheral sensory nerve numbing effects, it is sometimes used as an antispasmodic and analgesic for conditions like stomach ulcers.

There is a famous story about the Meiji-era literary master Koyo Ozaki, who was suffering from stomach cancer and in pain with no good medicine available, when a tincture of this Greater Celandine was made and administered to him.
Bai Qu Cai is a crude drug listed in the Soviet Pharmacopoeia.

🔷 Medicinal effects

1. It is said that if you apply the orange-colored sap to a wart, it softens and erodes the tissue, causing the wart to fall off.

2. In the past, old, dirty ulcers caused by syphilis were washed with water in which a Greater Celandine tincture had been dissolved.

3. It is said that if you apply raw Greater Celandine sap to cuts or ringworm, the pain is intense, but it heals quickly. It is also said to be good for boils or insect bites.

4. Because it is a poisonous plant, it requires careful handling.

🔷 Greater celandine is a biennial plant that grows wild in a wide range of areas, such as at the base of hedges, the edges of thickets, and along roadsides.
The stem is 40-60 cm tall and hollow. Its texture is soft, and a characteristic feature is that when damaged, a thick, orange-colored, foul-smelling sap oozes out. The entire plant is covered in a powdery white coating and has hairs.
The leaves are alternate and pinnately divided, with blunt-shaped lobes. The upper surface of the leaf is pale green, while the underside is greenish-white with fine hairs.
Around May, it blooms with several bright yellow flowers on stalks.
The calyx consists of two elliptical sepals, 6-8 mm long, with sparse soft hairs on the outside.
There are four petals, 1.2 mm long, numerous stamens, and one pistil.
The fruit is rod-shaped, 3-4 cm long and about 2 mm wide; the seeds are 1-3 mm long, cylindrical, and have an aril.
🔷💙💙🔷

The above is from 'Great Collection of Medicinal Plants for Home Use'.
I think this is an informative and interesting book, as it also includes various anecdotes.