Lettuce Opium

Scientific Name(s): Lactuca sativa var capitata L. (garden lettuce)., Lactuca virosa L. (wild lettuce).
Common Name(s): Acrid lettuce, Garden lettuce, German lactucarium, Greater prickly lettuce, Green endive, Lettuce opium, Strong-scented lettuce, Wild lettuce

Medically reviewed by Drugs.com. Last updated on Sep 30, 2021.

Clinical Overview

Use

Lettuce opium has been used as a topical antiseptic, as folk medicine to ameliorate a variety of conditions, and as a narcotic substitute or enhancer. It is also a mild sedative and hypnotic. There is little evidence to support its use for any indication.

Dosing

There is no recent clinical evidence to support specific dose recommendations.

Contraindications

Contraindications have not yet been identified.

Pregnancy/Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.

Interactions

None well documented.

Adverse Reactions

Lettuce opium contains sesquiterpene lactones; therefore, oral ingestion may be associated with allergic reactions.

Toxicology

Injection of wild lettuce opium and valerian root has been associated with transient fevers, chills, abdominal pain, flank and back pain, neck stiffness, headache, leucocytosis, and mild liver function abnormalities in 3 young adults.

Scientific Family

• Asteraceae (daisy)

Botany

Widely cultivated, lettuce flowers from July to September. This biennial herb grows to 1.8 m. The large leaves can attain lengths of 0.46 m. The stalks are rich in a milky-white sap that flows freely when the stems are broken.USDA 2016

History

Lettuce opium has been used in folk medicine for indications ranging from aiding circulation to treating swollen genitals. In Europe, it is used as a substitute for opium in cough mixtures.Lewis 1977 In homeopathy, a tincture has been used for laryngitis, bronchitis, asthma, cough, and urinary tract infections.Schauenberg 1977 The juice of the stem covering yields a medicinal extract known as thridace, the use and efficacy of which is widely disputed.Grieve 1971

In Chinese medicine, lettuce preparations have been widely used. The dried juice has been recommended as a topical wound antiseptic, and the seeds have been used as a galactogogue (to increase the flow of milk in nursing mothers). It has been claimed that the flowers and seeds are effective in reducing fevers.Brown 1977 Lettuce opium products have been marketed as legal highs or narcotic substitutes intended to be smoked alone or in combination with marijuana to enhance potency and flavor.Huang 1982 Its analgesic and sedative attributes seem more based on fiction than fact.

Chemistry

Some confusion exists regarding the nomenclature of the products derived from L. virosa and related plants. Flowering lettuce plants contain large amounts of a milky-white sap, which has a bitter taste and strong opiate-like odor. When the juice is collected and is exposed to air, it turns a brownish color. This substance is called lactucarium, a mixture of compounds to which the touted narcotic properties of the product have been ascribed. Lactucarium has been reported to contain approximately 0.2% lactucin, a sesquiterpinoid lactone. Additionally, the mixture contains a volatile oil, caoutchouc, mannitol, and lactucerol (taraxasterol) (approximately 50%). Lactucerin, also found in the latex, is the acetyl derivative of taraxasterol, a widely distributed triterpene.Bachelor 1973, Brown 1977