How is cantharidine oil?

Throughout the ages, man has been concerned about hair loss and baldness, and there have been no shortage of smart ideas about how to cure hair loss or encourage re-growth. Here's a look at just a few of those weird and wonderful hair loss remedies:
The Ancient Egyptians began searching for a cure for hair loss thousands of years ago. In ancient times, it was believed that baldness equated with a man's loss of virility, and consequently the Egyptians made numerous efforts to beat the baldness curse. One such cure, involved a religious ritual to the Sun God, and then involved swallowing a concoction of onions, iron, lead, honey and alabaster. Another popular practice was to apply the fat from ibex (a wild mountain goat), lions, crocodiles, serpents, geese, and hippopotami to their scalps. Egyptian men also smeared their bald patches with chopped lettuce leaves to encourage hair growth. In case you're wondering why lettuce, not cabbage? Lettuce was associated with Min, the Egyptian god of virility.
In the 1800's there were hundreds of 'snake oil' hair loss treatments on the market all claiming to have miraculous results. One of these secret remedies, and perhaps the most famous was "Barry's Tricopherous which guaranteed to 'Restore the Hair to Bald Heads and to Make it Grow Thick, Long and Soft'. The active ingredients included: 97% alcohol, 1.5% castor oil, and a 1% tincture of cantharidine, which was thought to stimulate the scalp. Cantharidine is a chemical derived from the pulverized bodies of an insect known as the "blister beetle", so called because it produces a blistering effect when it comes into contact with human skin. So without a doubt, "Barry's Tricopherous" would have been very stimulating to the scalp, but excessive use would have been extremely painful and most likely in vain, as there is no proof that this chemical actually stimulates hair growth. Interestingly enough, this hair loss remedy sold for almost 100 years.