Avena – Oat Fruit (Avenae fructus)
|Latin name of the genus:||Avena|
|Latin name of herbal substance:||Avenae fructus|
|Botanical name of plant:||Avena sativa l.|
|English common name of herbal substance:||Oat fruit|
Latin name of the genus: Avena
Latin name of herbal substance: Avenae fructus
Botanical name of plant: Avena sativa L.
English common name of herbal substance: Oat Fruit
- I.REGULATORY STATUS OVERVIEW1
- Assessment Report
- Botanical synonyms
- REGULATORY STATUS OVERVIEW
- ASSESSMENT REPORT FOR AVENA SATIVA HERBA AND AVENA SATIVA FRUCTUS
- II. 1.1. Avena sativa fruits
- Organic acids
- II. 1.2. Avena sativa green herb harvested before flowering
- N-containing carboxylic acids: avenic acid A and B.
- Mineral substances: see Table 2.
- Table 2: Mineral content of fruits and green parts of Avena sativa (oats) (mg/100g)
- Oats seeds
- Green oats
- II.3. Pharmacodynamics
- Table 3: Overview of literature data regarding pharmacological activities of Avena sativa
- In vitro
- In vivo
- III.CLINICAL EFFICACY
- III.1 Dosage
- The following preparations have been used as traditional herbal medicines:
- Systemic use
- Cutaneous use
- Clinical trials
- Use during pregnancy and lactation
- Use as a sedative
- Cutaneous use
- Table 4: Traditional cutaneous use of Oats preparations
- Table 5: Use for other purposes
- Clinical data
- IV.2. Toxicity
- IV.3 Contraindications
- IV.4 Special warnings / precautions
- IV.6 Interactions
- IV.7 Overdose
- V.OVERALL CONCLUSION
- Table 6 Traditional uses for Avena sativa fruit and Avena sativa herb
I.REGULATORY STATUS OVERVIEW1
MA: Marketing Authorisation;
TRAD: Traditional Use Registration;
Other TRAD: Other national Traditional systems of registration;
Other: If known, it should be specified or otherwise add ’Not Known’
1This regulatory overview is not legally binding and does not necessarily reflect the legal status of the products in the MSs concerned.
2Not mandatory field
Avena orientalis Schreb., Avena chinensis (Fisch.) Döll.
REGULATORY STATUS OVERVIEW
ASSESSMENT REPORT FOR AVENA SATIVA HERBA AND AVENA SATIVA FRUCTUS
This assessment report reviews the available scientific data for Avena sativa herba and Avena sativa fructus.
In preparing this report, a number of data sources have been taken into account. The main ones are as follows:
•The results of a literature search carried out using the available references in PubMed (last observation April 2007).
•The Cochrane database (last observation June 2007)
•Monographs included in the reference list.
•Standard books on phytotherapy.
•Internet sites on ‘Avena’, ‘phytotherapy’ and specific therapeutic applications.
The plant is used for its fruits and also herb, harvested before flowering (Hänsel et al. 1992). In addition, some authors refer to use of the fresh plant just before harvest (Anand 1971; Bye et al. 1974).
II. 1.1. Avena sativa fruits
Several fractions and substances have been described for the fruits of oats (Daniels & Martin 1967, List & Hörhammer 1972, Lasztity 1984, Krug 1985, Schneider 1985, Frølich & Nyman, 1988, Nie et al. 2005; Bratt et al. 2003, Bryngelsson et al. 2002).
Sugar fraction: mucilage
Protein fraction: contains glutelin (> 50%) and avenin . The globulin of oats fruits could be separated into an acidic (32,500 – 37,500 Dalton) and a basic part (22,000 – 24,000 Dalton). The unreduced protein exists as
Various enzymes were identified, including
Lipid fraction: the grains of oats contain the highest lipid fraction among all feeding crops belonging to the family of the Poaceae. Unsaturated hydroxy fatty acids are formed by lipid peroxidase activity. Avenothionin was identified as a
Alkaloids: The indole alkaloid gramine is thought to be responsible for a weak sedative effect similar to Passiflora.
Figure 1: the alkaloid gramine
Organic acids: Diverse organic acids: malic, citric, malonic, aconitic, oxalic acid: (the latter up to 0.04%). Caffeic and ferulic acid have antioxidant properties. Avenanthramides are described as polyphenols in oats seeds. The latter represents a group of phenolic compounds which are not present in other cereal grains. Steaming and flaking of dehulled oat groats (inner kernel) resulted in moderate losses of avenanthramide Bp, while ferulic acid and vanillin increased. Avenanthramides Bc and Bf were not affected by steaming.
Figure 2: left: phenolic antioxidant, hydrolysed in equimolar proportions of caffeic acid, ferulic acid and an aliphatic alcohol (R = Me or H). Figure 3 Right:
Figure 3: Vanillosid, a vanillin glycoside, reported to make the aroma of the seeds attractive to horses.
The burned cinders (as) reported to contain 50 to 70% silicon dioxide (SiO2
Flavonoids: To date, 28 flavonoids have been identified in the seeds and the green parts of the plant. Rhamnosylisoswertisin may have phytoalexin properties, protecting the plant against mycoses. Also 3 flavonolignanes derived from the flavone, triticin, were isolated from Avena sativa herb. Figure 4. In the known compounds a coniferyl alcohol moiety is linked to the flavone by an ether bond. In a new natural product, it is linked by
Saponins may also protect oats against fungal infections. They are of the triterpene saponin type.
Steroids in the seeds like avenasterin and stigmasterin.
Vitamins: The seeds contain vitamins as indicated in the table below.
Table 1: Vitamin content of oats
Cyanoglycosides: Sprouts can contain the cyanoglycoside linamarin. The content declines during the development of the plant (two leaves stadium only 10µM/100g).
Green oats contain mainly pectin and SiO2, esters with polyphenols and mono- or oligosaccharides. These oligosaccharides can be incorporated in cellulose, facilitating the fixation of minerals. This fixation can have negative effects, described as for instance the rachitogenic factor when calcium is fixed in phytinic acid complexes from which dissociation is difficult. Fixation is also reported for phosphates.
II. 1.2. Avena sativa green herb harvested before flowering
The composition of this part of the plant is described by Hänsel et al. (1992).
N-containing carboxylic acids: avenic acid A and B.
Saponins: avenacoside A and B. These are glycosylated steroidal saponins. Leaves contain furostanol saponins. Avenacosid content of leaves varies between
Figure 5: Avenacoside A and Avenacoside B.
Avenacoside A : R =
Avenacoside B : R=
Flavonoids: e.g. vitexin derivatives. See above under oat fruit.
Figure 6: tricin derivatives isolated from Avena sativa herb.
Mineral substances: see Table 2.
Table 2: Mineral content of fruits and green parts of Avena sativa (oats) (mg/100g)
The avenanthramides were extracted with an ethanol: water (80:20) mixture and characterised with HPLC. Plasma levels were also detected with HPLC after oral gavage. Peak plasma concentrations were obtained after 40 minutes. Apparent relative bioavailability was limited to 1.3% for both avenanthramide A and B (using
Schneider (1985) gives an overview of pharmacological activities described in the literature. Most of the references are difficult to access (thesis, patents or poorly referenced documents).
Table 3: Overview of literature data regarding pharmacological activities of Avena sativa
Inhibitory activity on
Extracts of Avena sativa herb, made with different ethanol concentrations were tested in an in vitro model. A commercially available enzyme preparation of
More prominent inhibitions were obtained when the extracts were prepared with higher concentrations of ethanol (mean + SD):
•15% ethanol: 44.3 + 1.4 % inhibition
•30% ethanol: 57.2 + 0.8% inhibition
•50% ethanol: 78.6 + 0.4% inhibition
These data were transmitted on file and no further details on the way the extracts were prepared and the way solvent controls were incorporated were given (Frutarom, data on file 2008). Also the number of assays per extract was not transmitted.
Inhibitory activity on
The same extracts (see ‘Inhibitory activity on
Extracts prepared with higher concentrations of ethanol gave higher inhibitions of the
•15% ethanol: 35.3 + 3.3% inhibition
•30% ethanol: 66.5 + 1.2% inhibition
•50% ethanol: 89.5 + 2.4% inhibition
These data were transmitted on file and no further details on the way the extracts were prepared, the number of assays and the way solvent controls were incorporated were given (Frutarom, data on file 2008). Inhibition of
Both series of experiments open interesting perspectives as a neurogenic activity of Avena sativa is concerned. As these preliminary data are on company file, more work has to be done in order to gain insight in the mechanisms of action exerted by Avena sativa extracts. None of the results has been published in peer reviewed journals up to now.
The potential antiatherogenic activity of partially purified avenanthramides from oats was tested by evaluating their effects on adhesion of monocytes to human aortic endothelial cell monolayers, expression of adhesion molecules and production of proinflammatory cytokines and chemokines by the endothelial cells. The avenanthramides were prepared by refluxing and purified by column chromatography. The
There was a
The recent investigations described above have mainly been carried out using secondary metabolites isolated from fruits. They cannot be considered as directly linked to the traditional uses of Avena sativa. Further in vivo clinical investigation needs to be undertaken.
Vasoactive intestinal peptide (VIP) was used as trigger to cause inflammation in human skin cell culture. Vasodilation was significantly increased after application of VIP. After treatment with oatmeal extract oligomer, the mean surface of dilated vessels and edema were significantly decreased. Moreover, treatment with this extract decreased
The same author tested a spray containing Rhealba oat extract on human skin fibroblasts. Then a punch biopsy as a source of epidermal cells was implanted on this dermal equivalent, where a multilayered epidermis developed. Epidermal growth was evaluated by immunohistochemical analysis of mitotic activity
Aries et al. (2003 and 2005) found an inhibition by a colloidal extract of Avena sativa (Avena Rhealba®) of the
prostacyclin (measured as
Cytokines represent a large series of regulatory proteins of the immunologic system. They are produced by cutaneous cells during inflammatory processes. Examples are interleukins (e.g. IL2, IL4, IL5 and IL13) produced in atopic conditions, contact eczema and psoriasis. A colloidal extract of Avena stimulated the production of the
During cutaneous inflammation processes the
Aries (1999b) studied the activity of Avena flour preparations on an experimental wound healing model. The expression of the Vascular Endothelial Growth Factor (VEGF) by human keratinocytes in the Boyden chamber was induced and augmented the migration of keratinocytes and collagen fibre contraction.
These in vitro investigations are indicative of an
Non specific effects on brain activity were investigated after oral administration of Neuravena® (EFLA®955 = standardised wild green oat extract, Frutarom Industries Ltd) to rats (quantitative information on the dose administered was not given). Oral gavage was continued over a 90 minute period. EEG was recorded during 5 hours using the
The effect of Neuravena® was also studied in behavioural trials. A group of 12 rats was administered a dose of 1g/kg body weight with their food over a period of 7 weeks. Another group received a tenfold dose and a control group received a normal diet. The results indicated enhanced stress coping abilities and alertness as well as improvement in general learning performance and speed of learning. Moreover, a positive effect on social behaviour was observed. A subsequent pathological examination also confirmed that Neuravena® was well tolerated in this subchronic treatment (Frutarom data on file).
To our knowledge the study of these neurological effects are a first approach to the traditional use of Avena sativa herb in different conditions related to stress. More investigations are welcomed and the publication in peer reviewed journals of the data mentioned above are highly recommended.
Avena sativa and Amaranthus hypochondriacus were used in a comparative study. Antioxidant compounds were compared in both species (2 varieties of the latter were studied). Polyphenols, anthocyanins, flavonoids and
Each experimental group consisted of 12 rats. Avena as well as amaranth kept cholesterol, LDL- cholesterol and triglycerides lower as compared to the
The oral or parenteral oat
The cholesterol lowering potency of
These in vivo experiments are partially useful in the development of well established use indications. They should be coordinated with clinical trials preferentially done with standardised preparations of oats seeds.
The following preparations have been used as traditional herbal medicines:
•The mucilage of oat fruits is traditionally used without specification of an exact dose.
•Tincture of Avena is also mentioned by Madaus (1938), without any further specification. Most probably it is made from Avena herb as most of the indications are referring to the central nervous system.
•The ‘Urtinktur’ (mother tincture) is made of fresh seeds (1/10) 100g, water 233 ml and alcohol 94.9 vol.% ad 1000ml. No dose is specified (List & Hörhammer, 1972).
•The British Herbal Pharmacopoeia recommends a liquid extract of the seeds (1:1) in 25% alcohol:
•The mother tincture of the fresh herb as described in HAB34 is mentioned (Schneider 1985).
•In Germany a preparation called ‘Schoeneberger naturreiner Heilpflanzensaft Hafer’ is available (Anonymus 2008)
•According to some sources homeopathic preparations with the same tincture in potencies from D3 to D200 can be used:
•Of the herb harvested before flowering, one teaspoon (+ 3g) is mixed with 250ml boiling water. After cooling, the water is sieved from the mixture and taken several times a day as well as before sleeping (Hänsel et al. 1992).
•When used to influence smoking habits, Avena sativa fresh plant was selected just before harvest: 1.5 parts of the crushed whole (weight) plant in 5 parts of 90% ethyl alcohol (volume) kept at room temperature with frequent agitation for 72 hours and then filtered. Of this filtrate, 1ml was diluted with 4ml of water and this preparation was taken 4 times a day (Anand, 1971; Bye et al. 1974).
•For a bath of 150 to 200 litres, 60g Avena flour is prescribed; for children 50% of this dose is used.
•Preparations of Avena seed flour are used. Colloidal extracts of flour are incorporated in a vehicle (e.g. petrolatume) in a concentration up to 20 to 30%.
•‘Aveeno®’ products contain the colloidal extract in different forms:
–‘Aveeno oatmeal®’: to be added to water for bathing.
–‘Aveeno oilated®’: nonsensitising protective oil added to the oatmeal.
–‘Aveeno ointment®’: Lassar paste with the starch component replaced by colloidal oatmeal.
•Liquid paraffin with 5% oatmeal was used to treat burns.
•Mostly fruits of Avena sativa are prepared as ‘colloidal oatmeal’ described in the USP 30 (1990). It consists of the powder obtained by grinding the whole fruits, resulting in oat flour and mixed with water. Viscosity, limits of microbial contamination, water content, particle diameter and ash composition are specified.
Effect on uric acid excretion
Two studies have been conducted with a combination herbal product. There are no studies with Avena preparations as a single component.
A group of 51 patients with elevated uric acid levels was treated with a tea formula containing Avena sativa (green oats 75%), Urtica dioica (herba 10%), Hypericum perforatum (herba 10%) and Alchemilla alpine (herba 5%). The treatment period was 4 (n=21; mean age 58) or 8 (n=30; mean age 39) weeks. The posology was not reported. In both groups serum uric acid levels were lower at the end of the treatment periods as compared to the initial levels: 8.87mg% versus 7.09mg% and 9.31mg% versus 6;45mg% respectively (Krug 1985).
The same tea formula was compared in an open
Studies with single component oat preparations:
The effects of colloidal oatmeal derivates in daily use of some products for skin care on 300 children. After 3 months of treatment the cutaneous conditions improved according to the physicians in 201/263 children. Parents increased satisfaction level during the study as their judgement regarding the products was “very good” in 153/263 cases after 2 weeks of treatment and in 201/263 cases after 3 months (Camplone et al. 2004).
Treatment with colloidal oatmeal was applied to 11 patients with a rash induced by cetuximab, erlotinib, panitumumab and sorafenib. Of the 10 assessable patients, 6 had complete response and 4 partial responses, with no associated toxicities. Treatment with colloidal oatmeal lotion was considered to be effective in controlling the rash associated with epidermal growth factor positive cancers and tyrosine kinase inhibitors. It allowed continuation of the antineoplastic treatment (Alexandrescu et al. 2007).
Studies with combination products:
The efficacy and tolerability was evaluated of a new lotion containing menthol and colloidal oatmeal in patients with itch and cutaneous xerosis (n=54). Patients treated with Aveeno Skin Relief Moisturizing Lotion once daily for 3 weeks. After treatment, clinical examination, and the
The efficacy and safety was evaluated of
Randomized control trials
A number of studies have been conducted on various oat preparations. Some of the studies involved foodstuffs such as oats cereals and oat bran enriched muffins. These studies are included to illustrate current research on oat preparations
Effect on serum lipids
At the end of the treatment period, total cholesterol in the oats group was 197.3 (+ 25.0) mg% (initial value of 209.0 + 29.7 mg%). In the corn group total cholesterol did not change. The difference between both groups was significant (P < 0.0003). The change was nearly entirely due to a lowering of the LDL cholesterol as HDL cholesterol was not influenced (Karmally et al. 2005).
Following a 2 week
Caloric restriction, fat modification and oat bran supplementation were part of the nutritional regimen within a 4 week lifestyle health program for 235 patients with overweight and hypercholesterolemia. Patients were divided into 2 groups: one lifestyle group (n=136) and another with the same lifestyle but als
The food matrix or the food processing, or both, could have adverse effects on the hypercholesterolemic properties of oat
Effect on blood flow and blood pressure
Brachial artery reactivity scans (BARS) were used to test the effect of oatmeal (60g) against vitamin C and E. The effect of acute (single dose) as well chronic (6 weeks) treatment was evaluated. Subjects (16 males > 35 years and 14 postmenopausal females) were treated in a randomized, placebo controlled,
A diet containing soluble
A cutaneous irritation double blind study with 12 volunteers was conducted by Vié et al. (2002). The participants were pretreated with 20 or 30% colloidal extracts in Petrolatume under occlusion during 2 hours. Control treatment consisted of Petrolatume. Sodium laurylsulfate was used as an irritant. Irritation was evaluated from the redness of the skin and cutaneous blood flow. Avena protected the skin from irritation as resulted from both parameters.
A comparison between 2 shower and baths oils was made during a 10 month period in 35 acute burns patients. The active product contained liquid paraffin with 5% colloidal oatmeal against the vehiculum (liquid paraffin). Patients were asked to rate their discomfort from itch and pain twice daily. Evaluation was made
The corticoid sparing effect of a cutaneous oat extract was evaluated in children (n=173 under 12 years old) with atopic dermatitis during 6 weeks. Children were randomly assigned to the active preparation or to placebo. Utilisation of local corticoids, the Scoring Atopic Dermatits Index (SCORAD) and the quality of life of the infants (Infant’s Dermatitis Quality of Life Index) and parents (Dermatitis Family Impact) were used as outcomes. There was a decrease of 42% of topical corticoid use in the intervention group (P<0.05) vs. 7.5% in the control group. The SCORAD index, and infants’ and parents’ quality of life significantly improved (P<0.0001) in both groups (Grimalt et al. 2007).
Clinical trials with oats preparations are of relatively recent origin. The possible therapeutic benefits of oats in case of hypercholesterolemia and cardiovascular complications cannot be considered as being within the traditional usage. The data available are not yet sufficient to support the efficacy of Avena sativa (fructus) in patients at cardiovascular risk; this aspect can be considered as an emerging science.
Although cutaneous use of Avena sativa has been studied in several open and controlled trials, a well established use cannot yet be accepted for several reasons. The patients included in clinical trials vary widely as far as their pathological condition is concerned. Children as well adults are studied. Inclusion of atopic patients, patients with iatrogenic rash due to the administration of several medicines, children who needed general skin care and patients with burns makes the evaluation of a well established indication difficult. The studies involved a range of different products with Avena sativa applied as an ointment or cream, oily liquid extract, colloidal oatmeal in liquid paraffin or as a lotion. The duration of treatment varied from 3 weeks to 10 months. Furthermore, the outcomes measured were quite variable: remission of skin lesions, level of satisfaction, skin dryness with physicochemical measuring of the moisture content of the skin, patient discomfort, Scoring Atopic Dermatitis Index (SCORAD) and quality of life. A well established use can only be accepted when the inclusion criteria (patients), the treatment (process) and the measured outcomes (product) are converging.
Use during pregnancy and lactation
No data available.
It is not known from what age Avena sativa has been used medicinally. Most probably the plant generated from Asia proxima. Cultivated oats are probably related to the species Avena fatua, originating from the Mediterranean Sea region. Oats were already cultivated 4000 years ago in Europe. Hippocrates, Plinius the Old and Galenus recommended oats for its tonic and feeding properties.
Hildegard von Bingen (12th century) describes the plant in her ‘Physica’: … may everyone who is exhausted with an empty mind take steam bath by poring water wherein oats have been cooked over hot stone. If this treatment is repeated, the patient will get to himself again and regain the capacity of thinking … (http://plantaardigheden.nl/plant/beschr/gonnve/haver.htm )
Rembertus Dodoneus (1608) mentioned Avena sativa as a useful treatment against bowel disorders and as a diuretic.
The traditional use of Avena sativa extends over several therapeutic areas (Leclerc, 1947, List & Hörhammer 1972; Madaus G Lehrbuch der biologischen Heilmittel 1938; Anonymus, British herbal Pharmacopoea 1976; Schneider 1985, Schneider 1990).
Use as a sedative
The traditional use as a sedating agent is reported in a number of sources.
… in der Amerikanischen Medizin findet eine Tinktur aus Hafer Verwendung als Nerventonikum bei Chorea, Epilepsie, Insomnie, nervöser Erschöpfung, Alkoholismus und während der Opiumentwöhnung. Allerdings wird die Wirksamkeit in letzterem Falle von sachverständigen Beobachtern sterk bezweifelt …
… The tincture of oats is used as a nervous tonic in the American medicinal practice in case of chorea, epilepsy, insomnia, nervous exhaustion, alcoholism and opium detoxification. According to objective reviewers the efficacy for the latter applications is doubtful …
List & Hörhammer (1972) mention the use of oats (seeds) mother tincture: … In der Homöopathie bei Neurasthenie und als Sedativum …
The British Herbal Pharmacopoeia (1976) and Hänsel et al. (1992) ,recommends the liquid extract 1:1 in 25% alcohol and a tincture 1:5 in 45% alcohol.
•Action: antidepressive, thymoleptic.
•Indications: depression, melancholia, menopausal neurasthenia, general debility.
•Specific indication: depressive states.
Schneider (1985) recommends oats in case of nervous exhaustion, insomnia and nervous weakness. For these indications the mother tincture of the fresh flowering plant is used (HAB34).
Van Elteren (2007) recommends Avena sativa in case of nervous irritation, depression, sleeplessness, nervous exhaustion, nervous weakness, hysteria. The seeds as well as fresh oats are used.
External use is frequently mentioned in the concept document by Fabre (2004).
In the table below detailed information is given about traditional cutaneous use. References with* are cited from Fabre (2004). In general there is an substantial tradition in Europe, in particular in France and Germany, and the USA.
Table 4: Traditional cutaneous use of Oats preparations
There is a patent from 1944 (Anonymus, 1944) on a special oats fraction, relatively low in starch and relatively rich in protein. The preparation is intended as an ingredient for cosmetics including hand lotions, face creams, for baths or for application where a high viscosity and adhesiveness are desired.
Table 5: Use for other purposes
When alcoholic extracts of Avena sativa (fresh plant selected just before harvest: 1.5 parts of the plant were used on a group of opium addicts several patients reported a loss of interest in smoking. These positive results could not be repeated in another clinical study (Anand 1971; Bye et al. 1974).
Should be useful in case of Premenstrual Syndrome (PMS) and depressions related to the menopausal status. Should also be an aphrodisiac for men as well as for women.
Oats can also lower the blood sugar with a positive effect on diabetes: in this case the mucilage is used to lower the amount of glucose.
Water preparations of Avena sativa can be applied as a gauze in case of all kind of dermatological problems like (wet) eczema, skin infections and psoriasis. Can also be applied in case of burns and itching.
External use is further mentioned as warm cataplasm in case of lumbago. Oats preparations should relieve inflammations of the skin and should help cicatrisation.
Avena sativa is used in case of diarrhea. It has a positive effect in liver function and stomach complaints. Regular use of oats optimizes defecation.
The mucilage in case of
The mucilage is used to sustain recovery in case of a serious disease and loss of appetite occurs.
In case of cough, gauze impregnated with an oats preparation should be applied on the throat. It is used in case of respiratory infections.
Since the 19th century Kneipp is a fervent promoter of the oats tea in case of rheumatic disease and gout. The tea is still recommended as a diuretic. Leclerc (1947) provided an exhaustive list of traditional applications of oats. They are among others related to urinary tract diseases.
Mutagenicity and carcinogenicity
No data available.
No data available.
An avenathramide enriched mixture did not show any cytotoxicity to human aortic endothelial cells in concentrations up to 40 µg/ml (Liu et al. 2004).
Irritation tests using colloidal extracts of Avena sativa revealed no ocular or cutaneous toxicity. There was no sensitisation or photosensitisation seen. Concentrations of 2 to 100% were tested (Fabre 2004).
Subchronic and chronic toxicity
There are no data available on oral use.
Colloidal Avena extracts are incorporated in different cosmetic formulations such as shampoo, soap, creams, ointments, emulsions and gels. These products have been available commercially since 1982. These preparations are classified as well tolerated with cosmetovigilance index of < 0.2/10,000 units.
No data available
The use of preparations containing Avena species is contraindicated for persons with a known hypersensitivity to this plant.
IV.4 Special warnings / precautions
Varjonen (1995) warned against cutaneous use of Avena preparations in atopic children, after investigating the effects of these preparations in prick tests. Most probably the protein fraction (46 to 66 KD) was responsible.
Seven preparations were dermatologically tested in 114 patients suffering from atopic dermatitis and 115 patients with contact eczema: 3 preparations containing 3% of different total oats extracts in petrolatum ointments or glycerolic solutions, 3 preparations containing 0.5% of different oats protein fractions also in petrolatum ointments or glycerolic saline and pure petrolatum as a control. Evaluation was made after 48 and 96 hours. In both dermatological conditions the frequency of allergic reactions was reported as reduced. (El Bakali et al. 2000).
Similar results were obtained with a group of atopic children (n=202; age: from 1 month to 15 years). A patch test with total oats extract (3%) or protein fraction (0.5%) in petrolatum and prick test with the same concentrations in glycerolic saline. Five children gave a positive reaction (= 2.4%) (Rancé 2001).
A double blind multicenter study was performed to test tolerability of oats in 116 children with newly diagnosed coeliac disease. During one year, one group received a standard gluten free diet, the other received wheat free oats (mean = 15g per day). Both groups did not differ significantly at the end of the study regarding coeliac serology markers or small bowel mucosal biopsies, including the numbers of intraepithelial lymphocytes (Högberg et al. 2004). Oats were well tolerated by coeliac patients (n=18). The median daily intake of oats was 93g/day (range
No data available.
No data available.
No data available.
Avena sativa L. has been known for more than 4000 years as a food and the traditional medicinal usage of Avena sativa has been documented since the 12th century.
The dried fruits have been used traditionally for the relief of various skin conditions as cutaneous treatments, such as bath preparations, as colloidal extracts of oat flour mixed with a suitable vehicle or as oatmeal in liquid paraffin.
The oat herb, harvested before flowering, has also been used traditionally as an herbal sedative usually administered as a herbal tea, as aqueous or ethanolic extracts or as expressed juice from the fresh herb.
Recent studies with cutaneous preparations show some benefit in treating various skin conditions. However, further evidence is needed from properly designed trials to substantiate the therapeutic efficacy of the preparations tested.
Similarly, recent investigations into the potential therapeutic effects of oat preparations on patients with hypercholesterolemia and cardiovascular complications are of interest but further evidence of efficacy from properly designed clinical trials is needed to confirm the therapeutic effects.
The clinical data available do not support well established medicinal use of Avena sativa fruit or Avena sativa herb.
On the basis of the traditional evidence, sufficient data are available to develop Community herbal monographs for Avena sativa fruit and Avena sativa herb.
The following traditional uses are supported by the bibliographic data:
Table 6 Traditional uses for Avena sativa fruit and Avena sativa herb
Avena sativa fruit
There are no significant safety concerns with the use of the fruit preparations provided they are not used by individuals who are hypersensitive to Avena species. Skin reactions may occur in atopic patients and those with contact dermatitis.
Avena sativa herb
There are no significant safety concerns with the use of the herb preparations provided they are not used by individuals who are hypersensitive to Avena species. The usual precautions for herbal sedatives also apply to Avena herb. In addition, caution should be advised in coeliac patients as data on possible protein content are usually not available.
Genotoxicity data are not available for Avena sativa fruit and Avena sativa herb and thus entries to the Community list are not possible at this time.