Effects of butterbur treatment in intermittent allergic rhinitis: a placebo-controlled evaluation

Efficacy and Safety of Phytotherapy and Anthroposophic Medicine in Seasonal Allergic Rhinitis: A Systematic Review

INTRODUCTION

Seasonal allergic rhinitis (SAR) is a common health condition that is associated with an increased risk for bronchial asthma. Besides conventional medicine, treatments from traditional, complementary and integrative medicine are widely used by individuals with SAR. This review aims to systematically summarize evidence on the efficacy, effectiveness, and safety of European/Western phytotherapy (PT) and medications from anthroposophic medicine (AM) in individuals with SAR.

METHODS

Four electronic databases were screened for clinical studies published between January 1990 and March 2023. The results were qualitatively synthesized and the study quality was assessed.

RESULTS

In total, 14 studies were included, 11 from European/Western PT and three from AM. About half of the studies were rated as being of sufficient quality. The most frequently studied plant was Petasites hybridus (butterbur), showing beneficial effects on immunological parameters, subjective symptoms, and nasal airflow. Beneficial immunological and clinical effects were also shown for an herbal preparation combining Citrus limonis (lemon) and Cydonia oblonga (quince). The medications examined by studies of sufficient quality were judged to be safe.

CONCLUSION

In summary, this systematic review highlights two herbal preparations, one from European/Western PT and one from AM, that appear to be promising options in the treatment of SAR.

Medicinal plants for allergic rhinitis: A systematic review and meta-analysis

Herbal medicine is popularly used among patients who suffer from allergic rhinitis. This systematic review and meta-analysis was conducted to evaluate the efficacy and safety of single medicinal plants in the management of allergic rhinitis. We searched MEDLINE, CENTRAL, and Web of Science for randomised controlled trials which evaluated the use of single medicinal plant for allergic rhinitis among adults and children. Twenty-nine randomised controlled trials (n = 1879) were eligible while 27 (n = 1769) contributed data for meta-analyses. Most studies (studies = 20) compared medicinal plants against placebo and Petasites hybridus was most frequently investigated (studies = 5). Very-low-to-low-certainty evidence suggests that compared to placebo, single medicinal plants may improve overall total nasal symptoms (SMD -0.31, 95% CI -0.59 to -0.02; participants = 249; studies = 5; I2 = 21%) especially nasal congestion and sneezing; and rhinoconjunctivitis quality of life (RQLQ) scores (MD -0.46, 95% CI -0.84 to -0.07; participants = 148; studies = 3; I2 = 0%). Moderate-certainty evidence show no clear differences between single medicinal plants and antihistamine in overall symptoms (Total nasal symptoms: SMD -0.14, 95% CI -0.46 to 0.18; participants = 149; studies = 2; I2 = 0%). As adjunctive therapy, moderate-certainty evidence shows that medicinal plants improved SNOT-22 scores when given as intranasal treatment (MD -7.47, 95% CI -10.75 to -4.18; participants = 124; studies = 2; I2 = 21%). Risk of bias domains were low or not clearly reported in most studies while heterogeneity was substantial in most pooled outcomes. Route of administration and age were identified to be plausible source of heterogeneity for certain outcomes. Medicinal plants appear to be well tolerated up to 8 weeks of use. Clear beneficial evidence of medicinal plants for allergic rhinitis is still lacking. There is a need for improved reporting of herbal trials to allow for critical assessment of the effects of each individual medicinal plant preparation in well-designed future clinical studies.

Allergies and Natural Alternatives

Complementary and integrative medicine therapies in the treatment of allergy and allergic rhinitis (AR) are divided broadly into the categories of nutritional supplements, herbal supplements, Ayurvedic, and Chinese traditional medicine. Some therapies are likely completely safe, such as Manuka honey, with no known side effects. Others have significant risks, such as ephedra, which was ultimately banned for use by the Food and Drug Administration. The efficacy of these therapies is varied and under-researched. The therapies with the strongest evidence in the treatment of allergy and AR are Manuka honey, butterbur, and Sinupret.

A review on the ethnobotany, phytochemistry, pharmacology and toxicology of butterbur species (Petasites L.)

ETHNOPHARMACOLOGICAL RELEVANCE

Petasites (butterbur, Asteraceae) species have been used since Ancient times in the traditional medicine of Asian and European countries to treat central nervous system (migraine), respiratory (asthma, allergic rhinitis, bronchitis, spastic cough), cardiovascular (hypertension), gastrointestinal (ulcers) and genitourinary (dysmenorrhea) disorders.

AIM OF THE REVIEW

This study summarized and discussed the traditional uses, phytochemical, pharmacological and toxicological aspects of Petasites genus.

MATERIALS AND METHODS

A systematic search of Petasites in online databases (Scopus, PubMed, ScienceDirect, Google Scholar) was performed, with the aim to find the phytochemical, toxicological and bioactivity studies. The Global Biodiversity Information Facility, Plants of the World Online, World Flora Online and The Plant List databases were used to describe the taxonomy and geographical distribution.

RESULTS

The detailed phytochemistry of the potentially active compounds of Petasites genus (e.g. sesquiterpenes, pyrrolizidine alkaloids, polyphenols and essential oils components) was presented. The bioactivity studies (cell-free, cell-based, animal, and clinical) including the traditional uses of Petasites (e.g. anti-spasmolytic, hypotensive, anti-asthmatic activities) were addressed and followed by discussion of the main pharmacokinetical and toxicological issues related to the administration of butterbur-based formulations.

CONCLUSIONS

This review provides a complete overview of the Petasites geographical distribution, traditional use, phytochemistry, bioactivity, and toxicity. More than 200 different sesquiterpenes (eremophilanes, furanoeremophilanes, bakkenolides), 50 phenolic compounds (phenolic acids, flavonoids, lignans) and volatile compounds (monoterpenes, sesquiterpenes) have been reported within the genus. Considering the phytochemical complexity and the polypharmacological potential, there is a growing research interest to extend the current therapeutical applications of Petasites preparations (anti-migraine, anti-allergic) to other human ailments, such as central nervous system, cardiovascular, malignant or microbial diseases. This research pathway is extremely important, especially in the recent context of the pandemic situation, when there is an imperious need for novel drug candidates.

Petasites for Migraine Prevention: New Data on Mode of Action, Pharmacology and Safety. A Narrative Review

Petasins are the pharmacologically active ingredients of butterbur and of therapeutic benefit in the treatment of migraine and tension headaches. Here, we summarize the pharmacology, safety and clinical efficacy of butterbur in the prevention of migraine attacks and present new data on its mode of action. We review published literature and study reports on the safety and clinical efficacy of the butterbur root extract Petadolex® and report new findings on petasins in dampening nociception by desensitizing calcium-conducting TRP ion channels of primary sensory neurons. Importantly, butterbur diminishes the production of inflammatory mediators by inhibiting activities of cyclooxygenases, lipoxygenases and phospholipase A2 and desensitizes nociception by acting on TRPA1 and TRPPV1 ion channels. It inhibits the release of calcitonin-gene related peptide (CGRP) of meningeal afferents during migraine attacks. We also evaluated the safety of a butterbur root extract in repeated dose studies for up to 6 months. A no-observable-adverse-effect-level at 15-fold of the maximal clinical dose (3 mg/kg/day MCD) was established for rats. At supratherapeutic doses, i.e., 45–90-fold MCD, we observed bile duct hyperplasia, and mechanistic studies revealed regulations of solute carriers to likely account for bile duct proliferations. Additionally, liver function tests were performed in cultures of primary human hepatocytes and did not evidence hepatotoxicity at therapeutic butterbur level and with migraine co-medications. Lastly, in randomized, double-blinded and placebo-controlled trials with Petadolex® migraine attack frequency was reduced significantly at 150 mg/day, and no relevant abnormal liver function was reported. Together, butterbur is effective in the prevention of migraine attacks by blocking CGRP signaling.

Alternative therapies for chronic rhinosinusitis: A review

The use of alternative medicine in chronic rhinosinus-itis (CRS) continues to increase in popularity, for the most part without meeting the burden of being based on sound clinical evidence. New and emerging treat-ments, both natural and developed, are numerous, and it remains a challenge for otolaryngologists as well as general practitioners to keep up to date with these therapies and their efficacy. In this systematic review, we discuss a number of alternative therapies for CRS, their proposed physiologic mechanisms, and evidence supporting their use. This analysis is based on our re-view of the English-language literature on alternative therapies for CRS (we did not include any therapies that are already recommended by accepted profession-al bodies). Data collection was performed using the PubMed database (not restricted to MEDLINE due to the nature of the subject matter), the Cochrane data-bases, and bibliography searches. We found that while many of the alternative therapies we reviewed might have a firm basis in science, they lack any clinical ev-idence to support their use specifically for CRS. Some emerging therapies, such as therapeutic ultrasonog-raphy and phonophoresis, show some promise, based on a growing body of positive evidence. In addition, the use of baby shampoo, thyme honey, and bromelain additives to saline lavage in CRS are all supported by clinical evidence, as is Sinupret, an oral preparation that contains echinacea. However, higher levels of ev-idence gleaned from large, well-designed, prospective, randomized, controlled trials are needed before any of these therapies can be recommended.

Complementary and alternative medicine for allergic rhinitis in Japan

BACKGROUND

Complementary and alternative medicine (CAM) is extensively used in patients with allergic diseases worldwide. The purpose of this study was to investigate the actual situation of CAM practice in the treatment of allergic rhinitis.

METHODS

We distributed questionnaires to otolaryngologists at 114 facilities in Japan. The subjects who participated in this study included children <16 years of age and adults ≥16 years of age diagnosed with allergic rhinitis by otolaryngologists. The survey was performed in the period from September 2007 to August 2009. Furthermore, we performed the same investigation out of the hospital setting, such as during general health examinations. All questionnaires were returned to Chiba University and analyzed.

RESULTS

The proportions of patients who had ever experimented with CAM in the hospital survey were 7.1% (225/3170) and 19.2% (1416/7363) of children and adults, respectively. Approximately 36.2% of the adult patients thought that the treatments were effective. The main reasons for CAM use were safety, convenience and low price. However, the group who spent more than $1000 on CAM felt more dissatisfaction and anxiety related to treatment at the hospital. The situation of CAM practice was not consistent and was instead influenced by the backgrounds of the subjects.

CONCLUSIONS

Many patients who receive CAM report feeling that the effects of treatment provided by hospitals are insufficient and have concerns about the side effects of such treatments. Information regarding standard treatments, as described in the guidelines, should become widely known and diffused, and strong communication with patients should be considered.

Integrative medical approaches to allergic rhinitis

PURPOSE OF REVIEW

Complementary and integrative medicine (CIM), formerly known as alternative medicine, is now part of the mainstream management for patients with a host of medical issues. This current opinion focuses on the use of CIM, more specifically, the use of nutritional and herbal therapies and homeopathic medications for patients with allergic symptoms.

RECENT FINDINGS

The literature review revealed that naturally occurring substances when compared with placebo more often than not resulted in significant improvement of the allergic rhinitis symptoms.

SUMMARY

Despite encouraging results, additional studies with greater rigor are needed.

Complementary and alternative therapy (CAM) in the treatment of allergic rhinitis

CAM is any therapeutic intervention that exists outside traditional allopathic medicine. The utilization in the US population is increasing up to 4 out of 10 patients in some surveys. Given this increasing prevalence, it is essential that clinicians have the resources to advise their patients in the utilizations, benefits, and potential harms of these alternative therapies. Recent literature was reviewed in regard to traditional Chinese medicine [TCM], acupuncture, homeopathy, and herbal therapy in the treatment of allergic rhinitis limited to randomized controlled trials. Several complementary treatment studies demonstrated statistically significant benefits to patients' quality of life and symptom scoring without providing duration of effect. Alternative therapy studies have revealed mixed results in regard to efficacy. Although the adverse effect profile is low, additional studies will be required to further promote integration into the standard of care for the routine treatment of allergic rhinitis.

Complementary therapies in allergic rhinitis

Objective. To determine the prevalence of herbal treatment of allergic rhinitis. Methods. In this prospective study, patients who were diagnosed with perennial allergic rhinitis were questioned about their use of natural products/herbal therapies for their symptoms. Results. In total, 230 patients were enrolled. Overall, 37.3% of the patients stated that they had used natural products/herbal therapies at least once. Women were more likely than men to use herbal supplements (38.3% versus 32.4%). Ten different types of herbal supplements were identified, with stinging nettle (Urtica dioicath), black elderberry (Sambucus nigra), and Spirulina being the most common (12.6%, 6.1%, and 5.7%, resp.). Conclusion. This study found a high prevalence of herbal treatment usage for the relief of allergic rhinitis symptoms in Turkey. The herbal products identified in this study and in the literature are discussed.

Phytoceuticals: the new 'physic garden' for asthma and chronic obstructive pulmonary disease

Phytoceuticals (non-nutritional but beneficial plant chemicals) merit investigation as pharmacotherapy for asthma and chronic obstructive pulmonary disease (COPD). Although asthma is mostly treated adequately, COPD is not. Thus, there is a need for new drugs with improved therapeutic benefit, especially in COPD. Recent interest in herbal remedies has redirected attention towards plants as sources of improved treatments for lung disease. Phytoceuticals from a variety of plants and plant products, including butterbur, English ivy, apples, chocolate, green tea and red wine, demonstrate broad-spectrum pharmacotherapeutic activities that could be exploited in the clinic. Well-designed clinical trials are required to determine whether these beneficial activities are reproduced in patients, with the prospect that phytoceuticals are the new physic garden for asthma and COPD.

Common respiratory diseases

The self-medication phenomenon in upper respiratory tract infections, rhinosinusitis, asthma, and chronic obstructive pulmonary disease are significant and will continue to increase. Current level of evidence is poor because of the small number of good quality studies, small sample size, short duration, and variation in the composition of the herbal interventions or therapies. The current review points to several potential therapies that could be effective either alone, or as adjuncts to conventional therapies.

Complementary/alternative medicines in allergic disease

Complementary/alternative medicines is a generic term that encompasses a variety of approaches, including homeopathy, acupuncture, phytotherapy and numerous holistic or behavioral techniques. Complementary/alternative medicines are widely used in a number of conditions, including asthma and rhinitis. The medical literature on complementary/alternative medicines is impressive, but there are few clinical studies conducted with an appropriate methodology, and their results are negative or conflicting. In general, the results are insufficient to provide recommendations for the use of complementary/alternative medicines in clinical practice. Regarding diagnostic techniques, none have demonstrated the capability of distinguishing between healthy and allergic subjects and none are able to identify sensitizations.

The minimal clinically important difference in allergic rhinitis

BACKGROUND

When presented with results from clinical measurements or research findings, clinicians must first make an interpretation of their importance, not only in statistical terms, but also the 'clinical importance' given the size of the change observed. To do this, they require an understanding of the relationship between their outcome measures, and the patient's perception of change. The minimal clinically important difference (MCID) illustrates this relationship by calculating the smallest change in a given outcome that is meaningful to a patient. There are few reports of calculated MCIDs in the Rhinology literature.

OBJECTIVE

To calculate MCIDs for common subjective and objective outcome measures in allergic rhinitis (AR).

METHODS

Nine randomized, blinded, placebo-controlled clinical trials in intermittent and persistent AR (pooled subjects, n=204) were analysed using anchor- and distribution-based approaches, applying regression and meta-analysis techniques.

RESULTS

MCIDs were obtained for the Mini Rhinoconjunctivitis Quality of Life Questionnaire: 0.4 units, peak nasal inspiratory flow: 5 L/min and total nasal symptoms score: 0.55 units. Nasal NO measurement changes had no correlation with patient perceptions of benefit.

CONCLUSION

Estimates of MCIDs were obtained for common subjective and objective rhinological outcomes. MCIDs can and should be applied by physicians interpreting research findings, as well as researchers reporting their findings. We can then be confident that our changes in practice will be of perceptible benefit to the patient.

Allergic rhinoconjunctivitis: complementary treatments for the 21st century

Even in the 21st century, some seeds of tradition remain firmly grounded regardless of the technological advancements of humankind. One such "tradition" involves using unconventional means-including mental healing, herbal formulas, and healing hand therapies such as acupuncture-to treat chronic illnesses. Although mental healing is unproven and energy therapy is not completely understood, acupuncture, herbal therapy, and sublingual immunotherapy have been described more extensively with mixed results that lack consistency and high-quality scientific data. Researchers are working to modernize these traditional therapies in the treatment of allergic disorders and using advanced technology to alter what some call "the earth's natural healing power" in hopes of developing a new, integrative form of medicine.

Complementary and alternative medicine: herbs, phytochemicals and vitamins and their immunologic effects

Complementary and alternative medicines (CAMs) are used in more than 80% of the world's population and are becoming an increasing component of the US health care system, with more than 70% of the population using CAM at least once and annual spending reaching as much as $34 billion. Since the inception of the National Center for Complementary and Alternative Medicine, there has been an enormous increase in the number of basic science and therapy-based clinical trials exploring CAM. The subspecialty of allergy and immunology represents a particularly fertile area with a large number of CAM therapies that have been shown to affect the immune system. Recent work has uncovered potential biochemical mechanisms involved in the immunomodulatory pathway of many supplemental vitamins (A, D, and E) that appear to affect the differentiation of CD4(+) cell T(H)1 and T(H)2 subsets. Other research has shown that herbs such as resveratrol, quercetin, and magnolol may affect transcription factors such as nuclear factor-kappaB and the signal transducer and activator of transcription/Janus kinase pathways with resultant changes in cytokines and inflammatory mediators. Clinically, there have been hundreds of trials looking at the effect of CAM on asthma, allergic rhinitis, and atopic dermatitis. This article reviews the history of CAM and its use among patients, paying special attention to new research focusing on herbals, phytochemicals, and vitamins and their potential interaction with the immune system.

S-petasin and butterbur lactones dilate vessels through blockage of voltage gated calcium channels and block DNA synthesis

Eremophilanlactones isolated from roots of Petasites hybridus (L.) G.M. et Sch. (Asteraceae) and S-petasin have vasodilatory effects with pD(2) -log (EC(50)) values of 6.01+/-0.08, 5.24+/-0.10, 4.74+/-0.13, and 5.43+/-0.06 for S-petasin, the (Z)-3-methylthioacrylic ester of 2beta-hydroxy-8betaH-7(11)-eremophilene-12,8-olide, the angelic ester of 2beta-hydroxy-8alphaH-7(11)-eremophilene-12,8-olide, and the angelic ester of 2beta-hydroxy-8betaH-7(11)-eremophilene-12,8-olide, respectively, in the mesenteric arteries. The pD(2) values were somewhat lower for all compounds in aortic segments. The vasodilation was caused by a blockage of the voltage gated calcium channels. S-petasin, (Z)-3-methylthioacrylic ester of 2beta-hydroxy-8betaH-7(11)-eremophilene-12,8-olide, and the angelic ester of 2beta-hydroxy-8alphaH-7(11)-eremophilene-12,8-olide displayed similar potencies in inhibiting DNA synthesis in cardiomyocytes and vascular smooth muscle cells.

Complementary therapy in allergic rhinitis

The term complementary/alternative medicine (CAM) refers to those therapeutic and diagnostic approaches different from conventional allopathic medicine. CAM may encompass homeopathy, acupuncture, phytotherapy, antioxidant therapy, and numerous holistic or behavioral techniques. Allergists and physicians of all disciplines are confronted with patients using CAM treatments, making it imperative that they become familiar with the scientific literature surrounding them. Given the high prevalence of allergic diseases and associated costs of CAM treatments, proof of CAM therapies is needed to establish appropriate guidelines for their use. Efficacy of CAM modalities should be established with randomized, double-blind, placebo-controlled trials, including adverse-effects monitoring. Of all the CAM therapies examined to treat allergic rhinitis, some herbal therapies and antioxidants demonstrate a trend toward some clinical efficacy. Researchers have yet to determine how to integrate these CAM modalities into the general treatment paradigm of allergic rhinitis.

Herbal medicines for the treatment of allergic rhinitis: a systematic review

OBJECTIVE

To evaluate the efficacy of herbal medicines for the treatment of allergic rhinitis (AR).

DATA SOURCES

Five electronic databases until November 8, 2005; bibliographies of located articles; manufacturers of commercially available preparations; and experts in the field.

STUDY SELECTION

We only included double-blind randomized clinical trials (RCTs), which tested a herbal medicine against placebo or active comparator, in patients with AR, and evaluated clinically relevant outcomes. Study selection, data extraction, and evaluation of methodological quality were performed independently by 2 reviewers. Discrepancies were resolved by discussion and by seeking the opinion of the third reviewer. Meta-analysis was only performed if data were considered suitable for pooling.

RESULTS

Sixteen eligible RCTs, testing 10 different herbal products against placebo or active comparator, were included. Six RCTs studied Petasites hybridus (butterbur) extract for AR and suggest that P hybridus is superior to placebo or similarly effective compared with nonsedative antihistamines for intermittent AR. Two RCTs studied an Indian herbal combination, Aller-7, in patients with AR and reported positive results. Single RCTs were identified for 8 other herbal products as treatments for AR, reporting positive outcomes, except for grape seed extract. The median methodological quality score was 4 of a possible maximum of 5.

CONCLUSIONS

There is encouraging evidence suggesting that P hybridus may be an effective herbal treatment for seasonal (intermittent) AR. However, independent replication is required before a firm conclusion can be drawn because of the financial support from the manufacturer of P hybridus extract to the 3 large trials. There are also promising results generated for other herbal products, particularly Aller-7, Tinospora cordifolia, Perilla frutescens, and several Chinese herbal medicines. Although these results are confined to the paucity of data and the small sample size, confirmation in larger and more rigorously designed clinical trials is warranted.

ARIA update: I--Systematic review of complementary and alternative medicine for rhinitis and asthma

Complementary-alternative medicines are extensively used in the treatment of allergic rhinitis and asthma, but evidence-based recommendations are lacking. To provide evidence-based recommendations, the literature was searched by using MedLine and the Cochrane Library to March 2005 (Key words: Asthma [OR] Rhinitis, [AND] Complementary [OR] Alternative Medicine, [OR] Herbal, [OR] Acupuncture, [OR] Homeopathy, [OR] Alternative Treatment). Randomized trials, preferably double-blind and published in English, were selected. The articles were evaluated by a panel of experts. Quality of reporting was assessed by using the scale validated by Jadad. The methodology of clinical trials with complementary-alternative medicine was frequently inadequate. Meta-analyses provided no clear evidence for the efficacy of acupuncture in rhinitis and asthma. Some positive results were described with homeopathy in good-quality trials in rhinitis, but a number of negative studies were also found. Therefore it is not possible to provide evidence-based recommendations for homeopathy in the treatment of allergic rhinitis, and further trials are needed. A limited number of studies of herbal remedies showed some efficacy in rhinitis and asthma, but the studies were too few to make recommendations. There are also unresolved safety concerns. Therapeutic efficacy of complementary-alternative treatments for rhinitis and asthma is not supported by currently available evidence.

Treating intermittent allergic rhinitis: a prospective, randomized, placebo and antihistamine-controlled study of Butterbur extract Ze 339

BACKGROUND

Intermittent allergic rhinitis (IAR) causes patients distress and impairs their work performance and quality of life. A variety of medicines are used by sufferers whose anguish frequently leads to trying new treatments, increasingly from herbal sources.

METHODS

Prospective, randomized, double-blind, parallel group comparison study of Butterbur extract (Ze 339; 8 mg total petasine; one tablet thrice-daily), fexofenadine (Telfast 180, one tablet once-daily) and placebo in 330 patients. Protocol and analysis were according to the latest guidelines on new treatments for allergic rhinitis. The primary efficacy variable was a change in symptoms from baseline to endpoint during daytime. The secondary efficacy variables were: (a) as per primary variable (evening/night); (b) Physician's global assessment; (c) Responder rates. Safety was closely monitored.

FINDINGS

Both active treatments were individually significantly superior to placebo (p<0.001) in improving symptoms of IAR, while there were no differences between the two active treatments (p=0.37). Superiority to placebo was similarly shown during the evening/night (p<0.001), by physicians' own assessment and by responder rates. Both treatments were well tolerated.

INTERPRETATION

Butterbur Ze 339 and Fexofenadine are comparably efficacious relative to placebo. Despite being a herbal drug, Butterbur Ze 339 has now been subject to a series of well controlled trials and should be considered as an alternative treatment for IAR.