Lavender has balancing and purifying effect on the senses so is excellent to help you maintain an all round healthy outlook on life. It can be a particularly welcome aroma if you chest or stomach is irritated or if you are feeling stressed, tense or having difficulty sleeping particularly when related to menstrual discomfort.
History
Lavender oil is one of the most popular but surprisingly it wasn't really until the Middle Ages that it began being used extensively. Primarily for treating headaches and people suffering with depression, during the Victorian era, it was famous as a sleep inducing aid and as a smelling salt.
Source
Lavender is a woody shrub around 1 metre high with the essential oil distilled from the flowering tops of the shrub. Originating from the Mediterranean, it is now cultivated worldwide.