Neurasthenia (also known as Neuralgia) was a term first coined by Beard in 1869 to describe a condition with symptoms of fatigue, anxiety and pessimism. It was explained as being a result of exhaustion of the central nervous system's energy reserves which Beard attributed to civilisation. In the late 1800s it became a popular diagnosis and led to rest cures.

Trigeminal neuralgia is a neuropathic disorder of the trigeminal nerve that causes episodes of intense pain in the eyes, lips, nose, scalp, forehead, upper jaw, and lower jaw. Trigeminal neuralgia is considered by most physicians to be the most painful condition known to man, and has, in fact, been called the, "suicide disease," because this has been the choice of many people who were unable to have their pain controlled with medications or surgery.