Citrus limon, limon
Lemon is a common fruit found in many parts of the world. The medicinal parts of the plant include the fruit, fruit juice, peel, and oil expressed from the peel. Expressed oil constitutes 2.5% of the peel, and consists mainly of monoterpenes (up to 70% limonene)j some sesquiterpenes, such as bisabolol several coumarins and furanocoumarinsj and citrus bioflavonoids, such as hesperidan, rutin, and naringoside. The juice contains bioflavonoids plus vitamin C. Pectin is mainly found in the white endocarp of the peel. The bioflavonoids are used to treat vascular insufficiency and problems with capillary fragility by decreasing porosity. Bisabolol possesses some anti-inflammatory activity. The coumarins and furanocoumarins are photodermatoxic. Various monoterpenes produce antispasmodic (1,8 cineole), antimutagenic (limonene), antitumor or chemopreventive (limonene), antioxidant (myrcene), irritant (terpinene-4-ol), and antiviral (a-pinene) actions. Lemon is available as fresh fruit, juice, essential oil, and extract.
Lemon is used extensively as a food and flavoring. The juice is a good source of vitamin C, potassium, and bioflavonoids. Lemon has also been used as a mild diuretic and has a mild anti-inflammatory effect. Lemon scent is often added to soaps, cleaners, and cosmetics.
Lemon is taken internally as an oil, tincture, and fresh fruit, and may also be applied topically.
Patients with known hypersensitivity to citrus should avoid the use of lemon. Ingestion of the expressed oil by pregnant women is contraindicated.
- Topical application oflemon to mucous membranes may cause irritation.
- Warn patient that application of lemon oil to skin exposed to sunlight may cause photodermatoxicity.
- Topical products should contain no more than 2% expressed oil to reduce toxicity.
- Alert patient to discontinue use should adverse skin reactions occur.
- Tell patient to remind prescriber and pharmacist of any herbal or dietary supplement that he’s taking when obtaining a new prescription.
- Advise patient to consult his health care provider before using an herbal preparation because a treatment with proven efficacy may be available.
The concepts behind the use of lemon and the claims made regarding its effects haven’t yet been validated scientifically.