Breaking teeth
At the time, the pharmaceutical industry had not yet developed to the point of having effective drugs. We are talking about the Old West, between the late 19th century and the early 20th century.
One of the most dangerous drugs was calomelan, which caused excessive saliva production. This was due to its high concentration of mercury. It was used for intestinal problems and as a laxative, but was fatal to teeth, which could even break.
The dirtiness of water
Since ancient times, water has been the main requirement for human survival in a region. That’s why ancient civilizations such as the Mayans and Incas developed sophisticated irrigation systems.
But in the Wild West, water came from open rivers and streams, which were often contaminated with animal feces and generated many diseases. Rainwater, collected with dirty buckets, was also unreliable.