Diazepam was patented in 1959 by Hoffmann-La Roche. It has been one of the most frequently prescribed medications in the world since its launch in 1963. In the United States it was the highest selling medication between 1968 and 1982, selling more than 2billion tablets in 1978 alone. In 2018, it was the 115th most commonly prescribed medication in the United States, with more than 6million prescriptions. In 1985 the patent ended, and there are more than 500 brands available on the market. It is on the World Health Organization's List of Essential Medicines.