The Frequency of Inquiries About Suspected Poisoning With Botanical Drugs

In the period 2014–2023 the Joint Poison Information Center in Erfurt (GGIZ, Gemeinsames Gifinformationszentrum) received primarily inquiries regarding medication exposures (adults 61%, children/adolescents 32%) [1]). Phytopharmaceuticals—which, unlike conventional medications, do not contain only isolated active ingredient molecules but whole plant extracts including different active ingredients and accompanying substances—are much used for numerous conditions (some 100–120 million packs in Germany every year) (2, 3). Many of these products are available over the counter, without the need for a prescription. They can, however, also have side effects. This study aimed to collect data on exposure inquiries regarding botanical drugs at a German poison information center.

Methods

We analyzed exposure inquiries to the GGIZ regarding prescription-only phytopharmaceuticals as well as those available over the counter (time period 2013–2022, human exposures, monotherapies or consideration of single toxic substances in severe symptoms, number of exposures n≥10).

Age groups are defined as follows: baby (<1 year), toddler (1 to <6 years), child (<14 years, exact age not known), school-age child (6 to <14 years), adolescent (14 to <18 years), adult (≥ 18 years). We calculated modified Litovitz risk factors (numbers of severe and moderately severe intoxications per 100 inquiries regarding one preparation) (Table). We used the poisoning severity score (PSS) to assess the severity of symptoms (4).

Table

Inquiries regarding exposures and severity of symptoms after ingestions of botanical drugs (Litovitz risk factor > 0) at the Joint Poison Information Center Erfurt in the time period 2013–2022

Results

With a set number of inquiries of n ≥ 10, we identified 36 preparations and 2512 exposures. Where the name of the preparation was not known and the ingredients did not differ substantially, we reported names of substances (for example, peppermint oil); otherwise we reported identifiers (for example, cold and flu bath essence). In 93.4% (2345) of cases the substances had been ingested. The most common exposure site was the family household (98.5%; 2474). Rankings included preparations using ivy leaf (24.8%, 622), peppermint oil (8.2%; 207), but also expectorants (5.5%; 139), hypnotic agents and sedatives (3.3%; 83), and valerian root products (2.2%; 56). The most common exposures were to Prospan cough linctus (22.4%; 562), Babix Inhalat N (inhalate solution) (17.5%; 439), peppermint oil (7.7%; 194), Sanopinwern/Eucabal Inhalat [Eucabal inhalation solution] (6.3%; 158), and cold and flu bath essences (3.7%; 93) (Table). 60% (n=1511) of inquiries concerned toddlers, 19% (n=479) adults, 15% (n=374) babies, 4.2% (n=106) school-age children, 1.2% (n=31) adolescents, and 0.3% (n=8) children. Exposure inquiries for the two most common preparations (Prospan cough linctus and Babix Inhalat N) concerned primarily children (94%; 529/562 and 66%; 289/439, respectively). In adults exposure inquiries were dominated by the ethanol-containing (79 vol.%) tincture Klosterfrau Melissengeist (which contains 13 plant ingredients and is used for a variety of complaints, from sleeplessness to cold symptoms, gastrointestinal symptoms, and feeling “under the weather”) (100%; 12/12), followed by the prescription-only preparation Colchysat Bürger (colchicine treatment for gout) (96.6%; 28/29), sage leaf tea (90.9%; 10/11), valerian tincture (90%; 9/10), herbal rubbing alcohol (73.5%; 36/49), clove oil (76.9%; 30/39), and thyme oil (58.8%; 10/17). The reasons for consulting the poison information center were primarily accidental exposures (64.5%; 1620) or confusion and mistakes regarding the preparation (25%; 629); improper use of medication was rarer (4.2%; 106).

Of all assessable exposures, 75.3% (1780/2365) remained asymptomatic; 23.5% (556/2365) were assessed as mild, 1% (24/2365) as moderate, and 0.2% (5/2365) as severe; in 147 of altogether 2512 exposures the degree of severity could not be assessed.

Suicidal intent applied to 46 (1.8%) of exposures and concerned valerian preparations (n=36), St John’s wort preparations (n=7), Colchysat Bürger (colchicine—n=4 including 2 completed suicides), Klosterfrau Melissengeist (n=3 including 1 completed suicide), herbal rubbing alcohol (n=2) and Prospan cough linctus (n=1). A further death resulted from inexpert use of Colchysat Bürger (colchicine). A lay intervention, and presentation to a doctor where necessary, was recommended in 87.9% (n=2209); inpatient treatment was advised in 5.9% (n=149) and outpatient treatment in 8.2% (n=207).

Discussion

Most of the inquiries (93%) to the Erfurt Joint Poison Information Center in this study related to oral exposures. Just under one-quarter related to ivy leaf extract. Ivy leaf contains α- and β-hederin, falcarinol, and saponins, which, at larger doses, irritate the gastrointestinal tract. The low Litovitz risk factors (Table) show, however, that as a rule, no severe symptoms are to be expected. On the other hand, the need for information is great, as evidenced by the multitude of inquiries.

Essential oils also rank among those substances that may cause problems. The corresponding Litovitz risk factors are >0, which means that at least moderately severe symptoms have been observed (partly Litovitz risk factors >5, which corresponds to rather high expected severity). In most cases, asthma, pertussis, and pseudocroup and a life age <2 years constitute contraindications to their use.

Toddlers were over-represented as a vulnerable risk group (60%). Differences in packaging for children’s and adult preparations as well as for orally administered versus externally applied preparations might have a protective effect. In adults, intoxications with colchicine preparations were observed (Litovitz risk factor 31). Colchicum alkaloids from the autumn crocus has a narrow therapeutic spectrum. For this reason, medical supervision is advised. In early symptoms (for example, nausea, diarrhea, abdominal pain), help from a doctor should be urgently sought.

Botanical preparations also require sufficient expertise and information from doctors and pharmacy staff. The relevant summary of product characteristics should be heeded, mistakes in use should be avoided, and oral and extraoral preparations should be kept safely and separately, and beyond the reach of unauthorized persons (for example, children, people with cognitive impairment, potentially suicidal persons). When these drugs are used according to the instructions, adverse drug reactions are overall rare, which underlines the great safety of such preparations in Germany.

The inherent limitations of this study include the limited representativeness of the data, possible misinterpretations as a result of nocebo effects, and lacking data as regards numbers of units sold and rates of use in the total population. We therefore cannot draw any conclusions about the risk posed by individual preparations from their absolute frequencies—these may actually result from such products’ popularity. Follow-up and verification options and the validity of the poisoning severity score are limited in the telephone setting. Furthermore, in view of the lack of specificness of many symptoms, any causal attribution is subject to uncertainty.

Conflict of interest statement

The authors declare that no conflict of interest exists.

Manuscript received on 9 March 2025, revised version accepted on 12 June 2025.

Translated from the original German by Birte Twisselmann, PhD.

Cite this as
Wendt S, Linden D, Prasa D, Franke H: The frequency of inquiries about suspected poisoning with botanical drugs. Dtsch Arztebl Int 2025; 122: 562–3. DOI: 10.3238/arztebl.m2025.0106

References

1. Gemeinsame Giftinformationszentrum Erfurt (GGIZ): Anfragen zu Arzneimitteln. www.ggiz-erfurt.de/arzneimittel.html (last accessed on 22 September 2024)

2. Ekor M: The growing use of herbal medicines: Issues relating to adverse reactions and challenges in monitoring safety. Front Pharmacol 2014; 4: 177

3. Bundesverband der Pharmazeutischen Industrie e.V. (BPI): Markt für Phytopharmaka in Deutschland 2019–2022: OTC-Sonderpublikation. www.bpi.de/index.php?eID=dumpFile&t=f&f=77593&token=f5f580db680c71354fe00b5362a158e6b791227d (last accessed on 30 May 2025)

4. Persson HE, Sjöberg GK, Haines JA, Pronczuk de Garbino J: Poisoning severity score. Grading of acute poisoning. J Toxicol Clin Toxicol 1998; 36: 205–13