Neurological disorders are diseases of the central and peripheral nervous systems. These disorders affect hundreds of millions of people all over the world. Globally, there are 47.5 million people with dementia. Dementia is the major cause of Alzheimer's disease (AD) in 7.7 million new cases who develop the disease every year. The prevalence of migraine is more than 10% worldwide. Patients with neurological problems may experience depression or anxiety. Herbal medicine has long been used to cure these diseases. One of these plants is lavender, which is composed of various compounds, including terpenes, such as linalool, limonene, triterpenes, linalyl acetate, alcohols, ketones, polyphenols, coumarins, cineole, and flavonoids.
Essential oils are abundant and volatile compounds obtained from plant parts, like leaves, seeds, and flowers through different methods, such as distillation. The flowers of this plant are used in decoration in ceremonies and its oil is also used in the cosmetics and perfume industry. This plant, especially as an essential oil, has various applications in medicine to treat psychological diseases, such as calming the nervous system, particularly in cases with depression, anxiety, and sleep disorders. Its positive effects on the nervous system are related to the impact of its volatile compounds on the hippocampus and amygdala.
Aromatherapy using its oil, especially in anxiety and sleep disorders, has been found with very promising results. Lavender has been employed using various methods in different studies, including inhalation, massage therapy, combined massage therapy with aromatherapy, and oral administration. It has also been used for the treatment of bloating and for wound healing (as an antibacterial and antifungal agent) and the treatment of insect bites. Lavender has analgesic, anti-inflammatory, and antispasmodic effects, as well.
Migraine is a chronic disease and according to the World Health Organization, it is the sixth most disabling disease worldwide among all neurological disorders. It has been reported that 17% of women and 6% of men have migraine. Nausea, vomiting, and sensitivity to light and sound are some of its symptoms. Migraine headaches with moderate to severe intensity, start on one side of the head. Different mental, environmental, and genetic factors are involved in the development of the disease. The headache frequency and severity are prevented by supplements and medicinal herbs. The effectiveness of traditional medicine and medicinal herbs has been demonstrated worldwide. Pharmacotherapy, massage therapy, acupuncture therapy, and aromatherapy are used for the treatment of migraine. The best treatment for relieving the symptoms of the disease is aromatherapy.
Based on a single-blind study assessing the effectiveness of the topical usage of lavender oil on migraine, 47 patients with migraine at the beginning of attacks, were administrated with two to three drops of a placebo solution (liquid paraffin) or lavender oil rubbed onto their upper lip followed by inhalation the vapor for 15 min. The procedure was employed for six consecutive migraine attacks. According to the results obtained from the 129 migraine attacks through the research period, the lavender group had a 3.6-point decrease in rating severity (on a 10-point rating scale), which was significantly more compared to the 1.6-point decrease in rating severity in the placebo group (obtained data from 68 attacks). The lavender group (71%) also showed a higher percentage of total or partial responders than the placebo group (47%). In addition, 74% of the subjects in the lavender group showed an improvement in migraine symptoms (vomiting, nausea, photophobia, and phonophobia) in comparison with only 58% in the placebo group. Also, the effect of lavender as a prophylactic therapy was investigated for migraine in a randomized controlled clinical trial. In a three-month trial, the group that received lavender showed a decrease in the frequency and severity of migraine attacks. Additionally, lavender oil was found to be effective in preventing migraines. Studies on human cell lines have indicated the efficacy of estrogenic and antiandrogenic properties of the lavender oil and it can be used in adults with an obvious allergy to lavender.