Protiodide

Protiodide is an iodide of mercury and was a very commonly used drug in the 19th century, prescribed for everything from acne to kidney disease. It was also the treatment of choice for syphilis. It was available over the counter at any drugstore, the most common form being a concoction of protiodide, licorice, glycerin and marshmallow.

Taken orally, and in low doses, protiodide causes excessive salivation, fetid breath, spongy and bleeding gums and sore teeth. Excessive use or an overdose causes physical weakness, loss of teeth, hemolysing (destruction of the red blood cells) of the blood and necrosis of the bones and tissues of the body. Early signs of an overdose or excessive use are muscular tremors, chorea, and locomotor ataxia. Violent bloody vomiting and voiding also occur.

Protiodide has long been banned as a medical remedy, even though it persisted in use as a quack remedy until the early 20th century. Morgan Robertson, known for his 1898 novel Futility which is famous for its similarity to the 1912 sinking of the Titanic, died in 1915 from what is suspected to be a protiodide overdose.