Wild Lettuce is also known as Lactuca virosa and is a plant in the Lactuca genus, ingested often for its mild analgesic and sedative effects, as well.
It was used in the 19th century by physicians when opium (and no, it's not opium) could not be obtained.
It was studied extensively by the Council of the Pharmaceutical Society of Great Britain in 1911.
They discovered two chemicals responsible for the medicinal properties of Wild Lettuce known as lactucopicrin and lactucin.
Today the plant is un-scheduled by the FDA, meaning it is legal to grow, purchase, and own without prescription or license.
The following is excerpted from Web MD:
Wild lettuce is a plant. The leaves, sap (latex), and seed are used to make medicine.
Wild lettuce is used for whooping cough, asthma, urinary tract problems, cough, trouble sleeping (insomnia), restlessness, excitability in children, painful menstrual periods, muscular or joint pains, poor circulation, and as an opium substitute in cough preparations.
How does it work?Wild lettuce has calming, relaxing, and pain relieving effects.
Note: Stop using wild lettuce at least 2 weeks before a scheduled surgery.