Anti-inflammatory and analgesic properties of Lavandula angustifolia - Essay Example

Critical evaluation of Anti-inflammatory and analgesic properties of the leaf extracts and essential oil of Lavandula angustifolia Mill. Introduction: The article “Anti-inflammatory and analgesic properties of the leaf extracts and essential oil of Lavandula angustifolia Mill” by Hajhashemi, Ghannadi and Shrif (2003) gives us an insight into the anti-inflammatory and analgesic powers of the plant under discussion. The popularity of the plant having healing powers can be traced back to the ancient Romans and Greeks. Even today its popularity is increasing with the passing years and was confirmed when it was declared “Herb of the Year 1999” by the Herb Growing Marketing Network in the USA (Anonymous, 1999). Practitioners such as Ebn-e Sina, Nafisy and Zargari have done exhaustive research on the plant, which is known in Iran as “Ostokhoddous”. In English language the plant derives its name from Latin “lavare” which means, “to wash” (Catherine and Kathi, 2001). As mentioned in the article, Lavender has been used for the treatment of stomachaches, kidney problems, infections, hair loss, anxiety, fever and sometimes infertility. Further more, it is also used as an antidepressant, antispasmodic, anti-epileptic, antiflatulent, diuretic and antiemitic. It has also been reported that lavender is also used for the topical treatment of insect bites. In modern age, Lavender oil is most often used for aromatherapy, in toiletries for a pleasant fragrance and also as an anti microbial agent. In this paper, the article is critically reviewed in order to understand the analgesic and anti-inflammatory properties of the plant in the light of the scientific research. Although research on the topic is limited and inconclusive, still some convincing information on the anti-inflammatory and analgesic properties of the plant can be collected from the available literature. Purpose: The aim of the research carried out in this article was to determine the analgesic and anti-inflammatory properties of lavender angustifolia by testing the hydroalcoholic extract, polyphenolic fraction and essential oil of the leaves. At the same time the constituents of the essential oil needed to be analyzed since it was believed that some of the compounds had the anti-inflammatory and analgesic properties. Method: There are different methods for the analysis of oils from the Lavandula spp. The standard method, however, is the gas chromatography with mass spectrometry (GC/MS), which has been adopted by the researchers in the article. Another method is the infrared spectroscopy (GC/IRFT). Both qualitative and quantitative analyses were carried out. The analyses clearly identified the chemical components of the essential oil and their percentage. The main constituents of Lavender oil are linalool (0.4%), linalyl acetate (0.6%) 1,8-cineole (65.4%), β-ocimine (0.1%), terpentine-4-ol (0.3%) and camphor (9.5%). It has been proved through research that linalyl acetate and linalool have sedative and anesthetic effects. Coumarin found in L. angustifolia has anti-inflammatory properties (Catherine and Kathi, 2001). It has been reported that 1,8-cineole has the ability to reduce inflammation (Santos and Rao, 2000). Hypothesis: The reason for which this research was carried out was the ancient belief that the herb Lavender angustifolia possessed the analgesic and anti-inflammatory properties. There have been mixed conclusions in the scientific history that support the hypothesis. Experiments have been carried out both in vitro and in vivo. Majority of them support the findings of the article, which confirms the analgesic and anti-inflammatory properties of the plant. In vitro data suggests that Eugenol, which is a small constituent in the lavender oils, has topical anesthetic effects (Catherine and Kathi, 2001). Tests conducted on animals suggest that linalyl acetate and linalool constituents in angustifolia showed significant local anesthetic effect. It also increased the number of stimuli needed to provoke palpebral closure in a dose dependant manner (Catherine and Kathi, 2001). Experiments conducted on human beings, however, have shown mixed results in relieving pain. In an experiment hospitalized children infected with HIV were given a massage of Lavender angustifolia. It was noted that the massage decreased the need for analgesic medication and relieved the continuous pain of some of the children completely (Styles, 1997). In a randomized control clinical trial conducted on 100 patients in a Critical Care Unit, the massage of lavender oil reduced the pain of the patients by 50%. 90% reduction in the heart rate was also reported by the participating patients (Woolfson and Hewitt, 1992). The use of L. angustifolia by the patients of rheumatoid arthritis has shown some mixed results. In a randomized control clinical trial nine rheumatoid arthritis patients treated with L. angustifolia massage reported no reduction in the level of pain. However the patients did report the reduction in the intake of analgesic medication. A quasi-experimental crossover study showed massage with L. angustifolia reduced the rheumatoid arthritis patients’ perception of pain and improved their quality of sleep and well being. However, these results were based on the patients’ own perception of pain since the data from the visual analogue scale did not record any reduction in the level of pain (Cavanagh and Wilkinson, 2002). Lavender oil has some benefits in midwifery as well. It has been reported that lavender oil added to bath water has reduced the level of discomfort and pain after childbirth (Dale and Cornwell, 1994). In the past due to its relieving power the plant poultices were applied at the back to relieve muscle tension during labor. Its application at the abdomen helped in placental expulsion. However no scientific evidence has been found to support the efficacy of the plant in the above mentioned situation. Due to its relaxing properties Lavender oils are used in labor rooms in many parts of the world to relieve the anxiety of the mother (Cavanagh and Wilkinson, 2002). Other researchers have also demonstrated the analgesic properties of the L. angustifolia plant. It is believed that L. angustifolia oil, linalyl acetate and linalool have shown anesthetic properties. It is believed that the mechanism of this action is related to the antimuscarinic activity and/or ion channel blockade (Ghelardini et al. 1999). L. angustifolia is particularly used for the treatment of nervous headaches and pain. Studies have suggested that L. angustifolia may have actions similar to “benzodiazepines and to enhance the effects of gamma aminobutyric acid in the amygdala (Tisserand, 1988)”. When lavender oil or extract is applied topically through massage, Linalyl acetate and linlool are quickly absorbed through the skin reaching peak plasma levels after 19 minutes. Linalyl acetate acts as a narcotic and linlool acts as a sedative. These properties of L. angustifolia thus play a major role in suppressing nervous headaches and pains (Cavanagh and Wilkinson, 2002). Lavender angustifolia aromatherapy is widely in use in medicine for the treatment of side effects such as aches and pains, hair loss and anxiety associated with chemotherapy. Its use in the palliative care has also been proved beneficial. Forty-two patients with advanced cancer were given L. angustifolia massage for four weeks. Significant improvement was noted in the sleep and depression scores of the patients (Cavanagh and Wilkinson, 2002). Due to the mixed results, it is necessary that proper and exhaustive research be carried out to understand the proper use of the plant. Lavender aromatherapy has also been found useful in the treatment of chronic or intractable pain. Several studies have shown that aromatherapy, with or without massage, can be useful in minimizing pain and acts as an analgesic both in children and in adults (Buckle, 1999). However, these studies are without any sufficient evidence due to which a definite conclusion cannot be drawn. Analgesic properties: The in vitro data showed that isolated mast cells of rats, on pre-incubation with lavender oil markedly reduced IgE-induced histamine release and tumor necrosis factor-alpha in a dose dependent manner (Kim and Cho, 1999). In another experiment carried out both on rats and mice showed similar kind of results. Rats and mice were pre treated with lavender oil either by topical application or by intra dermal injection. The result showed immediate reduction in the allergic and anaphylactic reactions in a dose dependent manner as measured by ear swelling (Kim and Cho, 1999). In another such experiment peripheral neutrophil activity after buccal mucosal injury was reduced when the rabbit was treated with the topical application of a wax that contained an amalgamation of sage, rose and lavender (Sysoev, 1991). Santos and Rao (2000) has also confirmed the anti-inflammatory properties of the herb L.angustifolia. In their experiment 1,8-Cineole, an essential component of the essential oil of L. angustifolia has shown an inhibitory effect on some experimental inflammation in rats. In mice, a similar kind of inhibition was noted in acetic acid induced increase in peritoneal capillary permeability. Inhibition was also noted in the chemical nociception induced by intraplantar formalin and intrapperitoneal acetic acid (Santos and Rao, 2000). Inconclusive reports on the anti-inflammatory effect of L. angustifolia have shown some positive results. In a health resort adult patients with chronic bronchitis were treated with inhalation of the essential oils of lavender and some other medicinal plants. The report was concluded with significant reduction in inflammation due to inhalation of the essential oils of lavender and four other medicinal plants. The frequency of the relapse was evidently reduced (Shubina, Siurin and Savchenko, 1990). Exhaustive research has been carried out on in vitro investigations. However, no clinical trials have been reported on humans and hence the evidence remains inconclusive. Childhood eczema has been considered as a difficult situation to deal with. Skin irritation can often become unbearable and causes distress to children in their sleep as well. As a substitute to the topical steroids, Lavender oil was trailed in order to access its usefulness against eczema. 16 children with eczema volunteered for the trail and were divided into two groups. The trail included Lavender oil massage for one group and the addition of a mixture of 3 oils (1:1:1) to bath water for the other group. The trial lasted for 8 weeks. Although the sample was small, still a considerable improvement was noted in the level of irritation and night sleep disturbance. Positive results were achieved in both groups (Anderson et al. 2000). Stress has also been linked to chronic skin problems. According to a recent research stress affects epidermal permeability barrier function and is a major precipitator of inflammatory dermatosis. For this reason, anything that is likely to minimize stress is also believed to have a beneficial effect on inflammatory dermatosis. Researchers have suggested that lavender massage aromatherapy can prove to be greatly beneficial in such a situation. The same research also suggests that aromatherapy diluted with essential oils helps in minimizing pain of the chronically ill patients (Buckle, 2001). Experiments: Experiments have been carried out on rodents to verify the analgesic and anti-inflammatory properties of the plant. As mentioned in the article, the tests included formalin test and acetic acid induced writhing test. Mice were divided into groups to study the results in comparison. Tests were carried out to study the analgesic effects of hydro alcoholic extract, polyphenolic fraction and essential oil of the plant. Whereas the hydro alcoholic extract (400-1600 mg/kg, p.o.) failed to show any significant result in the first phase. Its analgesic effect in the second phase was significant. Similarly, the polyphenolic fraction (800 and 1600 mg/kg, p.o.) and essential oil (100 and 200 mg/kg, p.o.) showed significant analgesic effects in both the first and second phases of the formalin test. The experiment therefore confirmed the analgesic properties of L. angustifolia. Anti-inflammatory properties of the plant were identified using carrageenan-induced paw edema test on rats. The hydrochloric and the polyphenolic extract (400 and 800 mg/kg, p.o.) of the plant did not show any significant anti-inflammatory results. On the other hand even a low dose of essential oil (200mg/kg) showed a 48% inhibition of carrageenan induced paw edema. The experiment thus proved the age-old belief that herb Lavender angustifolia has anti-inflammatory properties. Results: The results of all the experiments confirmed the anti-inflammatory and analgesic properties of the herb Lavender angustifolia. The results also confirm the scientific evidence and the rationale for the traditional use of the herb to reduce inflammation and as an analgesic. Conclusion: On critically analyzing the article, it can be stated that the basic objective of the research, which was to identify the analgesic and anti-inflammatory properties of the plant was scientifically confirmed through experiments. However, the report itself suggests that further research is needed in this field for more accurate results. References Anderson, C. Lis-Balchin, M. Kirk-Smith, M. (Sept. 2000). “Evaluation of massage with essential oils on Childhood Ectopic Eczema”. Phytotherapy Research 14(6): pg. 452-456. Anonymous. (1999). “Lavender to be promoted in 1999”, Countryside Small Stock Journal, 83, pg. 102. Buckle, J. (Sept. 1999). “Use of aromatherapy as a complementary treatment for chronic pain”. Alternative Therapies in Health and Medicine 5(5): pg. 42-51. Buckle, J. (2001). “Aromatherapy and Diabetes”, Diabetes Spectrum, 14: pg. 124-126. Catherine, J. Chu.and Kathi, J. Kemper. (2001). “Lavender”, The Longwood Herbal Task Force And The Center for Holistic Pediatric Education and Research. Retrieved on November 10, 2006 from www.longwoodherbal.org/lavender/lavender.pdf Cavanagh, H.M.A. and Wilkinson, J.M. (2002). “Biological Activities of Essential Oils”, Phytotherapy Research, 16, pg. 301-308. Dale, A. and Cornwell, S. (1994). “The role of Lavender in relieving perineal discomfort following childbirth: a blind randomized clinical trial”. Journal of Advanced Nursing, 19, pg. 89-96. Gherlardini, C, Galeotti, N, Salvatore, G. Mazzanti. (1999). “Local Anaesthetic activity of the essential oil of Lavandula angustifolia”. Planta Medica, 65. pg. 700-703. Kim, H.M. and Cho, S.H. (1999), “Lavender oil inhibits immediate type allergic reaction in mice And rats”. Journal Pharmacy and Pharmacology 51(22), pg. 221-226. Santos, F.A and Rao, V.S.N. (2000), “Anti-inflammatory and antinociceptive effects of 1,8- cineole a terpenoid oxide present in many plant essential oils”. Phytotherapy Research, 14, pg.240-244. Shubina, L.P. Siurin, S.A. and Savchenko, V.M. (1990). “Inhalations of essential oils in the combined treatment of patients with chronic bronchitis”. Vrachebnoe Delo, pg. 66-67. Styles, J. (Feb. 1997). “The use of aromatherapy in hospitalized children with HIV”. Complementary therapies in Nursing & Midwifery; 3(1), pg. 16-20 Sysoev, N.P. (1999). “The effect of waxes from essential oil plants on the dehydrogenase activity of the blood neutrophilsin mucosal trauma of the mouth”. Stomatologiia (Mosk). 70 (1), pg.12-13. Tisserand, R. (1988). “Lavender beats benzodiazipines”, International Journal of Aromatherapy, 1(1). Pg. 1-2. Woolfson, A. and Hewitt, D. (1992). “Intensive Aroma Care”, International Journal of Aromatherapy ; 4(2): 12-14. Read More