Hadacol was a patent medicine marketed as a vitamin supplement. Its principal attraction, however, was that it contained 12 percent alcohol (listed on the tonic bottle's label as a "preservative"), which made it quite popular in the dry counties of the southern United States. It was the product of four-term Louisiana State Senator Dudley J. LeBlanc, a Democrat from Erath in Vermilion Parish in southwestern Louisiana. He was not a medical doctor, nor a registered pharmacist, but had a strong talent for self-promotion. Time magazine once described him as "a stem-winding salesman who knows every razzle-dazzle switch in the pitchman's trade".
In 1943, LeBlanc conceived the idea that became "Hadacol" in New Orleans, when he had persistent pain in his foot and elsewhere. He asked a doctor to give him medication for pain: then he found that what the doctor gave him was a B-vitamin elixir, which he proposed to duplicate with a few changes and sell to a mass consumer market. (Years later, reports arose saying that LeBlanc had offered the doctor a share of the business, but the medical man refused. On a return visit, LeBlanc allegedly took a bottle with a few drops remaining of the medicine when the nurse had left the room.) LeBlanc said that his research showed that multivitamins taken collectively would yield greater results than a single vitamin for a specific problem.
The label on the tonic's bottle clearly stated that the recommended dosage (1 tablespoonful taken 4 times a day) was to be taken "...in a 1/2 glass of water after meals and before retiring". However, some pharmacies in dry counties were known to sell it by the shot-glass and at least one bar in New Orleans' French Quarter was known to sell a "Tassel Cocktail" with Hadacol as an ingredient. In Northbrook, Illinois, a suburb of Chicago, sales of Hadacol were limited to liquor stores.