Is Lavender a useful treatment for General Anxiety Disorder (GAD)?
Anxiety has become a common mental health issue that deeply impacts quality of everyday life of many .Anxiety and stress will be a common condition faced in clinical practice.Stress and anxiety can be the root cause of many diseases and thus it is important to address the root cause .“biomedical research have established positive associations between life stress and the development of a wide range of pathological disease
states”(Deak T et al 2015) Lavender’s longstanding traditional use ( since first century
AD) and the fact that it is still a popular herb today indicates it is an effective herb , and this encouraged this review . The 6 studies used in this review show a variety of human trials and internal investigation techniques eg MRI , CT , Saliva test etc and questionnaire type reports that monitor improvements in anxiety such as the Hamilton Anxiety Rating Scale. All studies conclude to suggest lavender has
Anxiety has become a common mental health issue in 2013 alone , 8.2 million people we diagnosed with anxiety in the UK. Anxiety manifests in psychological symptoms , feeling of unrest , stress , fear or worry that can occur to variable degrees and have variable manifestations. Natural treatments are becoming more popular therefore having effective treatment for anxiety would benefit my practice. “there was a 14% increase in the use of CAM over the five-year period.”(McMillen 2011). The aim is to find an effective , safe , economical herbal treatment with a low global footprint .
The Nervous System
The autonomic nervous system is responsible for all subconsciously controlled actions like breathing , heart beat and is also responsible anxiety . When the body perceives any threat it responds to it by releasing adrenaline and other hormones like cortisol activating the Sympathetic Nervous System (SNS) , a hormone that increases alertness mental function for problem solving, and heart rate to enable us to escape any physical danger . Anxiety triggers this response but because there is no immediate danger for us to flee the excessive hormones start to impact health . “Everything in physiology follows the rule that too much can be as bad as too little. There are optimal points of allostatic balance.”(Sapolsky 2004 )
Pathology and etiology
“The SNS dilates pupils of our eyes, shuts down the digestive organs, increases heart palpitations, relaxes the smooth muscles of bronchi and bronchioles, leading to “breathing problems”.(Plesman J 2011) Long term stress of GAD lead to deficiency not only as digestion becomes impaired but the nervous system burns trough minerals much faster when sympathetically active. Minerals and vitamins such as Magnesium , Vitamin C and other antioxidants and vitamins essential to cardiovascular and nervous function .Not only does this worsen the symptoms of GAD but it increases risk factors for other pathologies. “if stress causes your blood pressure to go up, then chronic stress causes your blood pressure to go up chronically. Task accomplished, you've got hypertension.” (Sapolsky 2004 p.212)
Many things are known to trigger it such as Trauma ( stress or mental or physical abuse),Genetics- Inherited physiology and pathways and mental and emotional cycles Long term Pain - emotionally draining also wears down the nervous system and the adrenal glands .Drug/substance abuse.Overactive area of the brain - can induce certain behaviors and emotions imbalance in Serotonin and noradrenaline .
Clinical Symptoms diagnosis and statistics
Emotional symptoms range from concentration difficulties to restlessness , nervous , tense irritability to panic attacks .
Physical Manifestations include :“dizziness, tiredness,a noticeably strong, fast or irregular heartbeat (palpitations),muscle aches and tension,trembling or,shaking,shortness of breath,stomach ache,feeling sick ,headache,pins and needles difficulty falling or staying asleep ”(NHS Direct 2017)
Diagnosis is obtained by talking to GP about symptoms , and their duration . Thyroid tests and blood tests could be carried out to ensure correct diagnosis . Anemia , overactive thyroid can also present with similar mental and physical symptoms.
Women are twice as lightly as men to develop anxiety ! “In 2013, there were 8.2 million cases of anxiety in the UK” (Fineberg et al. 2013) 6,233 took their lives and these are only reported cases . Many sufferers are silent . On average in any one week the rise in diagnosed anxiety in England alone is 6.6%. Considering this constant since 2013 the number has more than tripled.
-Conventional treatment for anxiety and side effects
Most common pharmaceutical drugs used :
SSRI-work by stopping the reabsorbing of the neurotransmitter serotonin in the brain causing high available levels of it. The Mayo clinic state that the wide range of SSRIs cause : Drowsiness ,Nausea,Dry mouth,Insomnia,Diarrhea,Nervousness, agitation or
restlessness,Dizziness,Sexual problems, such as reduced sexual desire or difficulty reaching orgasm or inability to maintain an erection (erectile dysfunction),Headache,Blurred vision. Studies show many other risks . “Increased risk of certain congenital heart defects among children of women taking SSRIs ”(Nembhard W. et al. 2017)
SNRI’s -block norepinephrine and well as serpentine causing same side effects with addition of tiredness .
Benzodiazepines -Works on the central nervous system occupying receptors of GABA in the brain enhancing the responses of neurotransmitters in the brain .Common side effects are “ dizziness, confusion or unsteadiness may persist in the elderly who are prescribed long-acting benzodiazepines. ...hypotension,cardiac arrhythmias,slow heart rate,apnea,respiratory depression,nausea/vomiting,blurred vision or double vision,skin rash,injection site reactions”(L. Anderson, PharmD, 2014)
Beta blockers - inhibit hormones like adrenaline to reduce HRV. Common side effects are the same as those of SSRI’s .
History of lavender benefits , uses and actions
Lavender originates from Mediterranean region like grows well in Europe, the US,UK, Australia and Arabian Peninsula. From economical perspective , lavender growing in many regions benefits practitioners and the environment if proven effective . It is believed that lavender has been used in herbal traditions since the first century AD by naturopath Dioscordes , who was involved in founding and developing herbal tradition. Ancient Egyptians considered lavender an essential for perfumes and incense.The Greeks and romans used it for relaxation . As time went on and we gained more experience with lavender we decided to make it the herb of love in the middle ages and considered it an aphrodisiac. “1999 has been dubbed the "Year of Lavender"; as a result there will be an increased demand for information and literature concerning all aspects associated with lavender production..”(Joe-Ann McCoy, Ph.D 2007)
Modern books suggest lavender acts via the parasympathetic pathway.“ Lavender has a strong reputation as a herb for the nervous system. Lavender has been used to calm
anxiety and boost mood for some time .”(Bone K,Mills S ,2013) So if modern research links lavender to parasympathetic activation , it may also back the hypothesis from the middle ages and Egyptians that perhaps it can help you fall in love as it stipulates the correct pathway. “ Lavender can be quite effective in clearing up depression ...and can also be used to promote natural sleep”(Hoffmann D 2003) .
Herbal safety and side effects
There is sufficient evidence that lavender in short-term treatment of various disorders is safe .With monitoring effects trough a wide range of modalities data suggests physiological improvements .There is a lack of long-term trials and studies and therefore needed to establish weather or not it is safe to use lavender long term to manage symptoms. Some studies do report side effects of lavender.and most defiantly be avoided or used with caution in patients with a known allergy.
A paper on 3 Prepubertal males suggests lavender causes Gynecomastia . “The common use of products containing lavender oil, tea tree oil, or both by the three boys and the resolution of their gynecomastia within months after ceasing use of those products suggest that these oils may possess endocrine-disrupting activity that causes an imbalance in estrogen and androgen pathway signaling.” (Derek V et al 2007) Tho it is possible these herbs may have estrogen effects ,there was no scientific evidence only speculations of this pathway. All endocrine blood levels were normal in all 3 boys before and after discontinuing the products .
The perimeters were not controlled : all 3 males used different products that contained either lavender or tea tree oil , other ingredients were not specified. All 3 males stopped using the products and saw an improvement or reversal Gynecomastia . Wether or not other treatment or lifestyle changes were applied was not stated or monitored .
In the orally administer trial , lavender had some slight adverse effects in the lavender group trailed against placebo group .The amount of gastrointestinal upsets infections and infestations, and some nervous system disorders were slightly higher in the lavender group .Irritations must of been minor as trial concluded “Lavandula oil preparation
Silexan is both efficacious and safe for the relief of anxiety disorder not otherwise specified.”(Kasper .S 2010)
In another study slight gastrointestinal adverse effects on an immediate basis that the lorazepam group ( Lazepram symptoms took longer to manifest and appeared to be more concerning ) but again none were described as serious . (Schläfkeb S ,Woelka H 2010 )
Studies do show that lavender should be avoided during pregnancy and breastfeeding as it may have emmenagogue effects and alter milk composition (Ernst 2017 )
Over species of lavender’s safety may not apply as the safety if internal use is not recommended “L.stoechas aqueous extracts have cytotoxic and genotoxic effects.” (Çelik, T, and Aslantürk.O 2007)
A systematic review of randomized clinical trials of Is lavender an anxiolytic drug? (Perry et al. 2012 )strongly suggests that lavender is a non dependent or addictive supplement .
The quality and purity of Lavender oil used in these studies reporting side effects would question seed (GMO) and growing conditions .Organic unmodified produce is one of the most important factor to maintain in essential oils and food and medicine as a whole . Most of these studies are US funded and tested .In the US have before scandals in the media regarding them buying rejected lavender products from France that was not grown or prepared to their standards distilled at ultra high temperatures with chemicals for quick production rather than the slower more natural way . “Check the market price , In case the market price is actually low , then the oil might be synthetic or fake”(Lambert .J 2014 ) On the general market the average price tends to fall below french and Bulgarian ( worlds top growers of Lavender ) market price for organic Lavender oil without specificity of the quality or concentration on label .Considering import and other fees , this can only indicate mainstream oil may be of low quality.After import it has been known for it to be cut with synthetic Linalool , proven to have no medicinal quality and to be highly liver toxic .Lavandin is most commonly sold and traded . Lavandin is a highbred modified species of lavender that has no
therapeutic benefits and very low plant constituent activity level .“marketing ploy by essential oil traders that advertise “approved” essential oils of ʻtherapeutic grade’ ”(Shutes J 2016) .Along with these go pure grade ,A and other grade all made up my marketing .’Certified pure therapy grade ’ is actually a trade mark owned by DoTERRA, LLC that has no external ratification .These are just a few examples of the many traps one can fall in whilst looking for an good product.Rule of thumb applies here as it does for most herbs and foods.Best authentic produce is organic certified , wild crafted and GMO free whilst ensuring the proper latin name is also on the bottle , and using your senses authentic oils are very strong ( most synthetics smell diluted ). Testing plant activity level should be a must of any trial and the insurance of quality non synthetic produce . On the trade impact document for US Imports of Essential Oils the word organic was not mentioned once.(ITC 2014) It is speculated by many media sources that 75% of available essential oils are contaminated. “most of them are worthless to your health and often synthetic”( Axe J 2016)
Gathering research the following search words were employed “free full scientific papers online” and “Free Medical Journals” the databases consulted were vast .Over 25 pages thoroughly checked for useful sites such as Ncbi, PubMed , Plosone, Repec, Elifescience , open access ,BioUniversityLibrary, omics online . On these sites words used were “ lavender” and “anxiety” yielded a good amount of papers easily with a wide variety to choose from . After reading a wide range of trials ,human trials were abundant and exceeded standards of other trails so this review will only include human trials .6 trials were selected based on number of participants ,depth of trial details and evidence of the most fair testing possible , sampling trials recorded in multiple ways as well as administered , and also comparing to conventional medications.Some studies were not chosen due to lack of information and fair testing. AnBooks such as Why Zebras don’t get ulcers , Medical herbalism , Principles of Phytotherapy , were used to understand the background of lavender and stress . Search phrases “lavender safety”and “quality of essential oils” and “essential oils uk data” and the names of unknown methods to me such as “stroop test” , J-SACL etc helped broaden knowledge on the subject .
Results and Discussion 1.Zabirunnisa, et al. (2014) ‘Dental Patient Anxiety: Possible Deal With Lavender
cluster randomised-controlled trial
significant reduction in anxiety
Number of groups
2 lavender and controlled ( no sent )
form of administration
Aromatherapy 1:1 lavender oil to water diffused for 15 minutes
number of participant
modified dental anxiety
15–24 , 25–34 , 35+
P < 0.001
Method of measuring result
modified dental anxiety scale and question
The scale the used is a modified to fit adults scale from the UK National Clinical Guidelines in Pediatric Dentistry. Age groups were allocated for accuracy in the case lavender is more effective in curtain age groups increasing the results P value. In the lavender group the mean rating of anxiety between ages decreased with age by at least 2 points where the controlled group increased . Suggesting age brackets 25–34 years, 35 years may benefit from lavender more than 15-24 group . This suggests modulation of receptors with age.There were 7-8 more women than men in each group that may effect the results if women are more responsive to lavender . None the less the mean anxiety scores between the two groups had a clear gap of 4 points on the anxiety scale favoring the Lavender group . “Comparison of anxiety scores between genders in Lavender group compared with control group showed statistically significant decrease in anxiety scores of both genders”(Zabirunnisa et al. 2014) All 287 lavender patients had moderate
to significant improvements in their anxiety .This study was monitored by questionnaire therefore scepticism was present when reading such promising results and question of possible placebo , leading to investigation of studies with internal examination techniques to provide some evidence .
2.Motomura N (1998) ‘A Psychophysiological Study of Lavender Odorant’
Human study (non specific)
Number of groups
3( stressed lavender , stressed placebo group , non stressed )
form of administration
Aromatherapy (20 mins)
number of participant
controlled group anxiety and none
20-23 (average 21)
Methods of measuring result
BP-Blood pressure and HRV , stroop test , stress/arousal adjective checklist
J-(SACL) Stress/arousal adjective checklist (SACL) a commonly used checklist since 1989 .Stroop test is testing the reaction time on a deliberately confusing test sympathetic or parasympathetic dominance .
The HRV increased only in lavender group and propped by 4 points in placebo group .The stroop shows increase in score ( mistakes made ) in the lavender group suggesting more parasympathetic dominance and in placebo mistakes decreased .
“These results suggest that lavender odorants have an anti-stress effect and reduce an arousal state.”( Motomura N 1998) Lavender group displayed decrease in blood pressure , increase in HRV and more mistakes made in stroop test suggesting degreased CNS and increased parasympathetic function . This wider selection of asseasment tecniques helps acredit the effects of lavender at the same time as clarifying the ways in which it reduces stress on the body.
3.Atsumi T, Tonosaki K. (2007) ‘Smelling lavender and rosemary increases free radical scavenging activity and decreases cortisol level in saliva’
Human controlled study
cortisol decreased by a significant amount
Methods of measuring result
salivary FRSA (free radical scavenging activity,) ,cortisol, secretory IgA, and α-amylase , HRV ,ECG.
form of administration
Aromatherapy (5 mins)
number of participant
premenstrual emotional symptoms ( mild to moderate )
20-23 (average 21)
“The HF power representing the parasympathetic nervous system activity markedly increased after the inhalation of lavender.”
“These findings clarify that lavender and rosemary enhance FRSA and decrease the stress hormone, cortisol, which protects the body from oxidative stress.”
- including salivary FRSA (free radical scavenging activity,) ,cortisol, secretory IgA, and α-amylase activity . 1,1-diphenyl-2-picrylhydrazyl was used to measure the FRSA levels in saliva and the findings show FRSA levels increased and cortisol decreased by a significant amount .Tho this is not a general anxiety study it may show modulation of powerful stress hormone ( cortisol ) and effects of lavender on nervous system function .
5.Bradley B et al. (2009 ) ‘Effects of orally administered lavender essential oil on responses to anxiety-provoking film clips.’ .
Randomized double-blind study
Methods of measuring result
State Trait Anxiety Inventory (STAI) , Positive and negative affect scale (PANAS),Heart Rate , galvanic skin response (GSR),HRV
form of administration
oral lavender capsules
number of participant
3 groups , placebo , 100 microl and 300 microl
anxiety-provoking film clips
200 microl group females only had secnificant increase in HRV and where males had a higher GSR .
“These findings suggest that lavender has anxiolytic effects in humans under conditions of
low anxiety, but these effects may not extend to conditions of high anxiety.”
Positive and negative affect scale (PANAS)-used to measure mood .Well known rated and widely used in the USA. Results showed significant reduction in HR and GSR and increased heart rate variability .In males the GSR response increased .Other measures were used such as such as : PET ,MRI and VBM all how drastic improvements. “These findings provide strong evidence that the anxiolytic effect of lavender essential
oil.” (Baldinger et al. 2014 )State Trait Anxiety Inventory (STAI)well astablished scale by Spielberger, Gorsuch, & Lushene since 1970 thorough questionnaire that has been
rated 86 to .95% reliability. This in depth study using a wide range of analysis was given grounds for research based on the Success of the Lazepram and Peroxatine trials (discussed below) along with the authorization of Salinax ( lavender ) Carried out investigation techniques used commonly by specialized hospitals across the world for internal investigations .
6 .& 7 .Kasper, S (2010 ) ‘Lavender oil preparation Silexan is effective in generalized anxiety disorder –
randomized, double-blind, double-dummy, multi- centre trial (with two stage design)
10 weeks of double blind treatment
form of administration
4 test groups. Salinax 160mg(128 patients ), Salinax 80mg(125) , Paroxitine 20mg(137) and placebo(136) .
Study lay out and perimeter
3-7 days wash out period prier with safety checks
“The HAMA total score decreased by 14.1 ± 9.3 points for Silexan 160 mg/d, 12.8 ± 8.7 points for Silexan 80 mg/d, 11.3 ± 8.0 points for Paroxetine, and 9.5 ± 9.0 points for placebo (mean ± s.d.).” (Kasper, S 2010)
The results support the title of this study . This suggests salinax is much more effective that the other variants .
“The protocol was reviewed and approved by the independent ethics committee of the medical faculty of the University of Würzburg, Germany. All patients provided written informed consent. The principles of good clinical practice and the Declaration of Helsinki were adhered to.” (Kasper, S 2010 )
Schläfkeb S, Woelka H (2010)‘A multi-center, double-blind, randomized study of the Lavender oil preparation Silexan in comparison to Lorazepam for generalized anxiety disorder’The study lasted 6 week comparing Lazepram to Salinax .Salinax results were only slightly more effected , However dosage was 80 mg is the lower dose used In the study above on Paroxitine . In this study 2 doses of Salinax were used 80mg and 160 mg .The HAMA score reduced by an extra 3 points with the higher dose ,strongly suggesting that if this study used a higher dose the result would of had more of a significant difference . Still at this low dose Salinax still appears to be more effective than Lazepram . Unlike many this study tested the reactivity of the lavender. “Salinax
method and demands for the main terpenoids linalool, linalylacetate and terpinen-4-ol
the %-values which must be in the range of 20.0-45.0, 25.0-46.0 and 1.2-6.0 respectively.” (Schläfkeb S., Woelka H 2010 )
Both of the studies above compare orthodox medication to Lavender use the Hamilton Anxiety Rating Scale to compare Lavender to pharmaceutical drugs .This scale is for patients who have already been diagnosed with anxiety . It measures the extent of the patients anxiety and to track improvement . Both of these studies show lavender is more effective .
Some speculation of placebo was present regarding studies documented via anxiety scale questionnaires however , other research recorded by a wide range of techniques of internal analysis and investigations show lavender is effective and show exactly how eg increases HRV. All investigation techniques showed improvement in anxiety from MRI to VDM , HRV , PET and Hamilton Anxiety Rating Scale and other questionnaire types .
Side effects reported , even tho considered minor , further investigation of the administered lavender preparation showed to potentially be the issue . Only one study tested the reactivity of the preparation and had specified reactivity range that they could use in the study . None the less , it was still not specified how it was prepared , wether or not it was mixed or derived from any synthetic material ( synthetic linalool is
commonly used ) or wether the plant was grown organically or without any other chemical interference . “its quality is effected by temperature , soil condition ...stored packed handled ..dark glass ,distilled instantly after harvest”(Lambert J 2014).Further studies with tested reactivity substance of organic lavender would be more of an interest to see wether or not even the minor side effects would still be present .
Overall sufficient evidence is present to suggest lavender does have strong anxiolytic effects . As for prescribing lavender or any herb , the client and factors such as ,digestive capacity , level of anxiety , gender and other presenting symptoms should be considered. Lavender should be used with caution in cases of endocrine irregularities as it is speculated to be estrogenic. (Derek V et al 2007).
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