Exodus wrote:... wondering where you've read about the "herbs touted for relaxation are anti-cholinergic"??? I've seen many, many lists of anti-cholinergic medications including all published Beers revisions, but haven't seen progesterone or herbs listed on them - would you be able to give sources . . . this is concerning!?! Exodus
I haven't seen it often and I didn't save what I did see. It wasn't in research papers but rather mentions on websites that I couldn't put my full faith in but which I found concerning. I should have said 'may be anticholinergic'. I don't have time to go beyond abstracts, but here are some things I found:
First is a paper studying three TCM herbal formulas for anticholinergic effects. I don't quite understand the abstract, but it appears to suggest that a given herb or herbal preparation may offset it's own AC effects.
The Screening of Anticholinergic Accumulation by Traditional Chinese Medicine
Abstract
Many Western drugs can give rise to serious side effects due to their ability to bind to acetylcholine receptors in the brain. This aggravates when they are combined, which is known as anticholinergic accumulation (AA). Some bioactives in Traditional Chinese Medicine (TCM) are known to block acetylcholine receptors and thus potentially cause AA. The AA of TCM was screened by quantifying the displacement of [³H] pirenzepine on acetylcholine receptors in a rat brain homogenate. We used a new unit to express AA, namely the Total Atropine Equivalents (TOAT). The TOAT of various herbs used in TCM was very diverse and even negative for some herbs. This is indicative for the broadness of the pallet of ingredients used in TCM. Three TCM formulas were screened for AA: Ma Huang Decotion (MHD), Antiasthma Simplified Herbal Medicine intervention (ASHMI), and Yu Ping Feng San (YPFS). The TOAT of ASHMI was indicative for an additive effect of herbs used in it. Nevertheless, it can be calculated that one dose of ASHMI is probably too low to cause AA. The TOAT of YPFS was practically zero. This points to a protective interaction of AA. Remarkably, MHD gave a negative TOAT, indicating that the binding to the acetylcholine receptors was increased, which also circumvents AA. In conclusion, our results indicate that TCM is not prone to give AA and support that there is an intricate interaction between the various bioactives in TCM to cure diseases with minimal side effects. [Emphasis added.]
I personally think their conclusion, inferring from three formulas to 'TCM' generally, isn't that scientific, but I do suspect that centuries of practice and observation probably ensure that traditional TCM formulas are safe in 'normal' patients. Maybe I would be more comfortable with TCM formula herbs for sleep as long as they have a long history of use. I know many turn to Ayerveda for this assurance as well. It's possible that some single herbs used outside of such traditional formulas are potentially more problematic (???).
One way such formulas may balance things out is if they have high flavonoid contents. This
paper, although focused on bone health (and very interesting in that regard!) says:
Flavonoids, a group of natural compounds mainly derived from plants, are known to possess osteogenic effects in bone cells. Here, we aimed to test if flavonoid could induce a cholinergic enzyme, acetylcholinesterase (AChE), as well as bone differentiation. In cultured rat osteoblasts, twenty flavonoids, deriving from Chinese herbs and having known induction of alkaline phosphatase (ALP1) expression, were tested for its induction activity on AChE expression. Eleven flavonoids showed the induction, and five of them had robust activation of AChE expression, including baicalin, calycosin, genistin, hyperin and pratensein: the induction of AChE included the levels of mRNA, protein and enzymatic activity. Moreover, the flavonoid-induced AChE expression in cultured osteoblast was in proline-rich membrane anchor (PRiMA)-linked tetrameric globular form (G4) only. In parallel, the expression of PRiMA was also induced by the application of flavonoids. The flavonoid-induced AChE in the cultures was not affected by estrogen receptor blocker, ICI 182,780. Taken together, the induction of PRiMA-linked AChE in osteoblast should be independent to classical estrogen signaling pathway. [Emphasis added]
Wow!
This one looks at the flavonoid content of chamomile exerting cholinergic effects, in contrast to what I once read that it has anticholinergic effects:
Evidence Supports Tradition: The in Vitro Effects of Roman Chamomile on Smooth Muscles [Piggies]
The crude herbal extract induced an immediate, moderate, and transient contraction of guinea pig ileum via the activation of cholinergic neurons of the gut wall. Purinoceptor and serotonin receptor antagonists did not influence this effect. The more sustained relaxant effect of the extract, measured after pre-contraction of the preparations, was remarkable and was not affected by an adrenergic beta receptor antagonist. The smooth muscle-relaxant activity was found to be associated with the flavonoid content of the fractions
Here are some more papers investigating single herbs. It's just a smattering to show that there is some work being done in this area:
Butterbur ...
'anticholinergic effect possible'. [I'm not sure how reliable 'jpub' is.]
Lemonbalm ...
'no cholinesterase inhibitory properties were detected'. [n=20]
Kava Kava and Echinacea ...
'The three main herbal products that contribute to dry eye are niacin, echinacea, and kava. There was a strong association between anticholinergic alkaloids and dry eye'. [I can't see what other herbs were covered in this review.]
St. John's Wort ...
'The observations suggest that the infusions of these Hypericum species possess antidepressant activity in mice, without inducing muscle relaxation, anticholinergic and sedative properties'. [Mice]
Hops ...
'The results support the involvement of nAChRs in memory improvement in mice by MHBA. MHBA is thus thought to activate the vagal nerve and enhance hippocampus-dependent memory via nAChRs'.
From this handful of papers the message I take away is not to make assumptions about herbal remedies.
I don't mean this next part to be scary or a call to avoid all herbal approaches, but I found recurring mention of contamination of herbs with
other plant matter that is anticholinergic causing ER visits. This appears to be
rare but something to be aware of. It might be good to list herbal supplement providers that can guarantee purity.
Anticholinergic Poisoning Associated with an Herbal Tea -- New York City, 1994
Anticholinergic syndrome caused by contaminated herbal tea; acting swiftly to identify the source.
Herbal Medicines Induced Anticholinergic Poisoning in Hong Kong
Worldwide Occurrence and Investigations of Contamination of Herbal Medicines by Tropane Alkaloids
I found that last one interesting because it equates nightshades (atropine) with anticholinergic effects. I knew nightshades could be a problem and I avoid them, but I hadn't realized any link to anticholinergic effects. This appears to be most notable with belladonna, 'the deadly nightshade'.
Abstract
Tropane alkaloids occur mainly in Solanaceae plants. In the present review, the main objective is to describe the worldwide occurrence and investigations of anticholinergic poisoning due to the contamination of herbal teas and herbs by tropane alkaloids. Tropane alkaloid poisoning can occur after consumption of any medicinal plant if Solanaceae plants or plant parts are present as contaminants. Globally, almost all reports in 1978-2014 involve herbal teas and one of the prescribed herbs in composite formulae. Contamination most likely occurs during harvest or processing. As for prescribed herbs, on-site inspection is necessary to exclude cross-contamination and accidental mix-up at the retail level. The diagnosis is confirmed by screening for the presence of Solanaceae species and tropane alkaloids. Herbal teas and herbs contaminated by tropane alkaloids can pose a serious health hazard because these relatively heat-stable alkaloids may exist in large quantities. The WHO repeatedly emphasises the importance of good agricultural and collection practices for medicinal plants. DNA barcoding is increasingly used to exclude the presence of contaminants (particularly toxic species) and product substitution. All suspected cases should be reported to health authorities so that investigations along the supply chain and early intervention measures to protect the public can be initiated. [Emphasis added]
This leaves one to wonder how often herbal supplements are contaminated with a steady drip of lower levels of these potentially AC compounds.
Well I haven't accomplished anything else I'd planned for this part of my morning, but thanks for sending me down this interesting rabbit hole!