Lamiaceae (Labiatae) Rosmarini folium; Rosmarini aetheroleum Dried leaves; essential oil (obtained from steam distillation of the flowering aerial parts) The leaves contain up to 2.5% essential oil, the composition of which varies according to chemotype, and contains camphor (5–31%), 1,8-cineole (15–55%), α-pinene (9–26%), borneol (1.5–5.0%), camphene (2.5–12.0%), β-pinene (2.0–9.0%), limonene (1.5–5.0%), verbenone (2.2–11.1%), β-caryophyllene (1.8–5.1%) and myrcene (0.9–4.5%). The leaves also contain flavonoids with a methylated aglycone (e.g. genkwanin and luteolin); phenolic acids, particularly rosmarinic, cholorogenic and caffeic; and terpenoids, including diterpenes (e.g. carnosol, carnosolic acid, rosmanol) and triterpenes (e.g. oleanolic and ursolic acids) (EMA 2010; Pharmaceutical Press Editorial Team 2013; WHO 2009; Williamson et al. 2013). Robust clinical data to support traditional medicinal uses of rosemary are lacking. Almost all trials using rosemary oil externally are using combination products for treating pain and muscle soreness. The aromatherapy use of rosemary oil is widely known but not well supported by clinical studies. One short-term randomised, double-blind, controlled crossover study has investigated the acute effects of different doses of rosemary leaf powder on cognitive function in 28 older adults (mean age 75 years). The ‘Cognitive Drug Research’ computerised assessment system was used at intervals up to 6 hours following oral administration of four different doses of rosemary (750, 1500, 3000, 6000 mg) or placebo. Doses were counterbalanced, with a 7-day washout period between treatments, spread over 5 weeks. Results demonstrated a biphasic dose-dependent effect in speed of memory: the lowest dose (750 mg) had a significant beneficial effect compared with placebo (p = 0.01), while the highest dose (6000 mg) had a significant impairing effect (p < 0.01). Several doses of rosemary exhibited deleterious effects on other measures of cognitive performance, but these were inconsistent and not dose dependent (Pengelly et al. 2012). Given the small-scale study, and varied effects of different doses of rosemary, it is not possible to draw firm conclusions as to the efficacy of rosemary in memory enhancement, and further research is required. A large number of studies have highlighted the diverse pharmacological actions of rosemary, a selection of which are summarised here.
Rosemary
Rosmarinus officinalis L.
Family:
Drug name:
Botanical drug used:
Main chemical compounds:
Clinical evidence:
Effects on cognition:
Pre-clinical evidence and mechanisms of action:
Diuretic effects:
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
