Organic Hallucinosis is the fourth studio album by Polish death metal band Decapitated. The album was released on February 7, 2006, in the United States, on February 13 in Europe, and on February 22 in Japan. The release was followed by European and North American tours. It is Decapitated's only album to feature vocalist Adrian "Covan" Kowanek, and their final album to feature bassist Marcin "Martin" Rygiel and drummer Witold "Vitek" Kiełtyka, who died at the age of 23 in an tour bus accident in Russia that also seriously injured Covan.