As the power of the Roman Empire declined, the lands to the south and east of the Mediterranean Sea became incorporated into the Islamic Empires. Some Muslims believe "hadiths", such as in "Sahih Bukhari", prohibits every intoxicating substance, though the use of intoxicants in medicine has been widely permitted by scholars. Dioscorides' five-volume "De Materia Medica", the precursor of pharmacopoeias, remained in use (which was edited and improved in the Arabic versions) from the 1st to 16th centuries, and described opium and the wide range of its uses prevalent in the ancient world.