High Quality Content by WIKIPEDIA articles! Dihydromorphine (Paramorfan, DHM, Paramorphan) is a semi-synthetic opioid invented in Germany in 1900. In structure, it is very similar to morphine, the only difference being the reduction of the double bond between positions 7 and 8 in morphine to a single bond. Dihydromorphine can be made by several processes, including hydrogenating morphine or opium or by demethylating either dihydrocodeine or tetrahydrothebaine. Dihydromorphine is available as tablets for oral use, ampoules of solution for injection by various routes, suppositories, and liquids for oral and sublingual use.