The informant is a 47-year old accountant working in California, originally from Michoacán, Mexico. She lived a modest life as a young adult, having to take care of her family at a very young age while still finding success in management. She then moved to the United States with her husband to raise their family and now works in accounting. She primarily speaks Spanish with English as a second language. He shall be referred to as MB.
MB explained that this was a home remedy she learned from her own mother. It is a simple matter of mixing a solution of rubbing alcohol and salt, then rubbing that over a persons feet and lower legs to cure a cold. MB herself could not explain how it worked (and it certainly doesnt seem to make any sense on a medicinal level), but she asserts that it always managed to cure a cold both in her childhood and for her children when she became a mother.
MB explains that rubbing alcohol is a common ingredient in home remedies, as it was a cheap and accessible resource for those without too much money where she grew up. As mentioned above, these solutions were very simple and meant to be easily executed before relying on a doctor for medical advice. Money was often very tight, so any kind of folk remedy was preferred to a costly visit to the doctor (except, obviously, in cases that required it).
I believe that the seemingly non-medicinal nature of this remedy is reflective of MBs Catholic origin. As the town was made up largely of the devoutly religious, they were unlikely to question that which made no scientific sense and instead function more on faith. After all, there doesnt seem to be any scientific reasoning for either of these remedies, but MB insists that they served their purpose for herself and her siblings. At the same time, I can personally testify to the reliability of the salt-alcohol solutionI do not know how it works, but only that it can clear up a cold overnight.