DOES IT WORK?Celandine and digestive ailments
CELANDINE IS the name given to two different species of yellow wildflowers common across Ireland and much of Europe. The eight-petal “lesser celandine” belongs to the buttercup family and is one of the first wildflowers to blossom during the winter, sometimes appearing as early as December.
Although viewed by some as a weed, William Wordsworth admired the lesser celandine, writing three poems about it. A picture of celandine was included on a memorial commissioned for the church where Wordsworth is buried. However, the wrong species was carved on the stone. The species on the Wordsworth memorial is “greater celandine”, an unrelated member of the poppy family whose flowers have four petals and bloom much later in the year.
Little harm resulted from the mix-up with the memorial, but misidentifying medicinal herbs can lead to serious problems. In this case, greater celandine is generally toxic, while the young leaves of lesser celandine have been used in salads and are rich in vitamin C (older leaves can be toxic, though). Greater celandine contains isoquinoline alkaloids, some of which are highly toxic, but others can be used for medicinal purposes. The key is ensuring the right parts of the plant are used and in the right quantities.
When stems of greater celandine are cut, a yellow sap flows. This sap has been used to treat warts as it is caustic, but it can also irritate healthy skin and cause severe irritation if ingested. Herbalists traditionally use the leaves and young stems to treat a variety of stomach and intestinal ailments. The roots are used less often as they contain higher concentrations of the toxic alkaloids.
Laboratory studies with tissues and animals have shown that celandine stimulates production of bile. This liquid is produced in the liver and released into the small intestine to help with digestion. Increased bile production could therefore explain how celandine might relieve intestinal problems.
However, no trials of greater celandine for gastrointestinal ailments were found. Several randomised controlled trials have been conducted with a German product containing greater celandine and eight other herbs. A number of these are known to have beneficial intestinal effects. While the combination product showed significant benefits, it is impossible to know how greater celandine contributed to these effects.
Another product, Ukrain, is a semi-synthetic derivative of one alkaloid in celandine. Produced in the Ukraine, it is most commonly given intravenously. Early studies have shown promising results in treating a range of cancers.
However, all the studies published to date were small and had other deficiencies, and none were randomised controlled trials. Although this preparation shows promise, it differs from the herbal material because it is a chemically modified form of one substance purified from the herb.
Greater celandine’s ability to stimulate the liver to produce bile has also raised concerns about adverse effects. A study released this year found 17 published cases of liver problems arising in people consuming greater celandine.
The most common symptoms were jaundice, itching and fatigue, typically developing about two months after using greater celandine.
Medical examination revealed enlarged livers in most patients. The symptoms usually resolved two to six months after ceasing the herb. Most people were consuming other drugs at the time they took the herb, so it was unclear if the problems were due to the herb or the combination of herb and certain drugs. Anyone with liver problems, or taking medicines or herbs with a risk of damaging the liver, should not take greater celandine.
While greater celandine has a long tradition in treating intestinal ailments, evidence from controlled trials is not available. Given that there are effective and safe treatments for most of these conditions, and that greater celandine has been linked to serious adverse effects, its use cannot be recommended.
Further research is needed on its constituents to identify whether specific compounds or their derivatives may be clinically useful. Ukrain is one such derivative which warrants controlled clinical trials.
- Dónal O'Mathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University. He is author of Alternative Medicine: The Christian Handbook, Updated and Expanded Edition, Zondervan, 2007
