- Fever grass
- Barbed wire grass
- Silky heads
For Patients & Caregivers
Lemongrass has antioxidant, anticancer, and antimicrobial properties, but it has not been studied in cancer patients.
There are over 140 species of lemongrass that are prevalent in many parts of Africa and Asia. It is widely used as a flavoring agent in Asian cuisine, in perfumery, and as an insect repellent. Lemongrass has also been traditionally used in folk medicine to treat anxiety, gastrointestinal problems, and to induce sleep. These effects have mostly been shown in animal studies. Lab studies showed that lemongrass can lower blood pressure, and has anti-inflammatory, antioxidant, and anticancer properties. More research is needed to confirm such effects in humans.
- To treat or prevent cancer
Although lab and animal studies showed that compounds in lemongrass can inhibit tumor growth or cause cancer cell death, human data are lacking.
- To lower blood pressure
Lab studies suggest that lemongrass can lower blood pressure by relaxing blood vessels. Human studies are needed.
- To improve sleep
Animal studies have shown that lemongrass injections can produce sedative effects. However, drinking lemongrass tea does not have the same effect in humans.
- To prevent infections
Lab studies show that lemongrass has activity against various microorganisms. A clinical trial of HIV/AIDS patients with oral thrush indicated that lemongrass is an effective antifungal treatment. It may also be helpful in addition to mainstream therapies for chronic gum disease.
- To reduce inflammation
Lab and animal studies showed favorable results, but human data are lacking.
- To reduce anxiety
Clinical studies show that lemongrass tea does not lower anxiety or produce calming effects. However, briefly breathing in lemongrass essential oil might speed recovery from some types of anxiety. More studies are needed to confirm this effect.
- You are undergoing chemotherapy: Lemongrass can act as an antioxidant and may reduce the effectiveness of some chemotherapy agents.
- You are taking drugs that are glutathione-S-transferase substrates: Although no interactions have been reported, ingesting quantities of lemongrass over standard culinary use may increase the risk of side effects of these drugs.
- You are taking drugs that are cytochrome P450 substrates: Although no interactions have been reported, ingesting quantities of lemongrass over standard culinary use may increase the risk of side effects of these drugs.
- You are pregnant: Citral and myrcene in lemongrass caused birth defects in rats.
Oral: Dizziness, drowsiness, dry mouth, excess urination, and increased appetite.
In high doses, essential oil of lemongrass can damage liver and stomach mucous membranes.
Excessive intake of lemongrass tea may also affect kidney function.
Topical: Skin rash with the use of lemongrass essential oils
Delayed skin rash from both topical and oral use: In a 52-year-old massage therapist who also practiced aromatherapy with essential oils including lemongrass. Her rash also came back after she drank lemongrass tea.
For Healthcare Professionals
The genus Cymbopogon consists of several lemongrass species (1) that are prevalent in the tropical regions of Africa and Asia, (2) including C. citratus (West Indian) and C. flexuosus (East Indian). Lemongrass is widely used as a flavoring agent in Asian cuisine, in perfumery, and as an insect repellent (6). It has been used in folk medicine as a sedative (3), to reduce gastrointestinal problems (4), and for its central nervous system-depressant effects (5). It is traditionally consumed as a tea and used in aromatherapy.
In vitro, lemongrass exhibits antimicrobial (21) (23) (24), antibiofilm (25), anti-inflammatory (26), neuroprotective (27), vasorelaxant (10), and antidiabetic effects (28). Lemongrass extracts and constituents have shown antioxidant, antiproliferative, and apoptotic activity (8) (9) (29) (30). Animal models also suggest anticancer (31), anti-inflammatory (32), anti-allergic (33) (34), and anxyolitic activity (35), as well as protective effects on various organ systems (36) (37) (38) (39) (40).
In human pilot studies, lemongrass essential oil formulations were a helpful adjunct to periodontal therapy for patients with chronic periodontitis (41) and helped reduce oral thrush in HIV-positive patients (7). Lemongrass demonstrated antifungal activity against pityriasis versicolor, but was not as effective as ketoconazole (42).
In other studies evaluating lemongrass tea consumption, erythropoiesis-boosting effects were observed, suggesting possible uses in the treatment or prevention of anemia (43). However, lemongrass tea may also produce dose- and time-dependent adverse effects on renal function (44). Other studies have not found lemongrass tea ingestion to reduce anxiety or to benefit sleep (5). However, brief inhalation of lemongrass essential oil may help to accelerate recovery from some types of anxiety compared with controls (45). More studies are needed to confirm this effect.
Chlorogenic acid, isoorientin, and swertiajaponin were identified as the active constituents in lemongrass that possess antioxidant properties to prevent endothelial dysfunction via a nitric oxide-independent vasodilatador effect on blood vessels (46). In vitro, anti-inflammatory effects of lemongrass occur through inhibition of IL-1beta (26), and proteasome and nuclear factor-kappaB pathways by chlorogenic acid (47). In rat cerebellar granule neuron cultures, neuroprotective effects were attributed to antiapoptotic activity that occurred with cell cycle arrest in the G0G1 phase (27).
In animal models, anti-allergic and anti-inflammatory effects were attributed to the major constituents citral and geranial (33). The anti-inflammatory effects of citral were further attributed to PPAR-gamma activation (38). Lemongrass inhibits release of the inflammation marker myeloperoxidase from neutrophils and suppresses IL-6 and IL-1alpha production in mice peritoneal macrophages (13). A lemongrass hexane extract modulated allergic asthma via inhibition of nuclear factor kappa B activation (34). Analgesic effects by the constituent citronellol are attributed to inhibition of peripheral mediators as well as central inhibitory mechanisms (22). Anxiolytic activity of lemongrass appeared to be mediated by the GABAergic system (35). It also altered onset and duration of convulsions and potentiated sleep time through GABAergic mechanisms (3), and increased seizure threshold by blocking seizure propagation (15).
In humans, the erythropoiesis-boosting effects produced with lemongrass tea consumption are likely due to its nutritional constituents and antioxidant and pharmacologic properties (43). As aromatherapy to revert reactive anxiety, lemongrass essential oil appears to act through the olfactory or nose-to-brain pathways to restore homeostasis (45).
Several constituents in lemongrass demonstrate anticancer activity. Isointermedeol upregulates tumor necrosis factor receptor 1 leading to apoptosis through the extrinsic Fas pathway (2) (11). It also increases mitochondrial expression and activation of caspase-9 via the intrinsic cell death pathway. Citral induced apoptosis via caspase-3 enzymatic activity in human leukemia and breast cancer cells (8), and induced glutathione S-transferase (GST) through an electrophilic interaction with glutathione in rat liver epithelial cells. GST functions in cell detoxification by rescuing cells from oxidative damage and carcinogenic compounds (9) (12). Cytotoxicity was attributed to the presence of an unsaturated aldehyde group, which is specific to the geranial isomer of citral (9). Polysaccharides from lemongrass produced cytotoxic and apoptotic effects in cervical and prostate carcinoma cells via caspase 3 upregulation and Bcl-2 downregulation followed by cytochrome c release (29), and antitumor and immunomodulatory activities in sarcoma-180 tumor cells were attributed to immunoenhancement rather than direct cytotoxicity (31).
Topical: Contact dermatitis (48).
Delayed contact dermatitis (topical and oral): In a 52-year-old massage therapist who also practiced aromatherapy with essential oils including lemongrass. Her cutaneous symptoms also recurred following ingestion of lemongrass tea (49).
- Glutathione-S-transferase (GST) substrates: Citral, found in lemongrass essential oil, was shown to induce GST (9).
- Cytochrome P450 substrates: Beta-myrcene in lemongrass can interfere with cytochrome P450 liver enzymes (19) (20), although lemongrass-prescription drug interactions have not been reported.