'Jus viperinum': Francis Home (1719-1813) and his experiments on the benefits of viper broth in skin disease.

Francis Home (1719-1813) was a Scottish physician and medical author. Here we consider his biography and three brief accounts of experiments on viper (i.e. adder flesh) broth in the treatment of skin disease ('Herpes or Lepra Gracaeorum'). After a fortnight of treatment one patient was improved but not cured (discontinued due to lack of vipers), one 'almost cured' but refused further treatment at 'disgust' of discovering its contents, and one dismissed cured. The second case constitutes a basic 'cross-over' model as it led to comparison of viper with snail broth in the same patient. Home concluded that viper broth was beneficial for skin disease but his findings did not lead to wider adoption of the treatment. His reported clinical benefits likely arose from improved hydration, protein and cessation of other treatments. Home does not discuss his small sample size or present quantitative outcomes. Home's methods were not influenced by Lind's (1753) methodology for comparing treatments. As both were Edinburgh-trained Scots who served in the British military forces, this reveals the limited communication between clinicians of the day. Home appears to have faced many practical challenges, including accessing vipers, motivating patients' participation and the risk of concomitant treatment with other drugs.