Dihydromorphine

Dihydromorphine (Paramorfan, DHM, Paramorphan) is a semi-synthetic opioid invented in Germany in the first years of the twentieth century. Structurally, 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.

Dihydromorphine is slightly stronger than morphine as an analgesic with a similar side-effect profile. Like hydromorphone also tend to burn off more quickly, with a mean duration of action around 3 hours in most patients.

At the present time, dihydromorphine is most commonly used in Japan, and is used, though still perhaps relatively rarely, in Europe but has in fact been used more and in greater overall quantities in recent decades in some countries such as the Czech Republic, Slovakia and others in the region. In the United States and other countries, it is most often seen these days as an intermediate in the manufacture of hydromorphone, and related drugs. It is available as the hydrochloride, hydroiodide, or monohydrate salt, with the former being the form almost exclusively used in pharmaceuticals but the hydroiodide also used especially in making dihydrocodeine hydroiodide (Paracodin). Individuals and organisations are lobbying for the United States to legalise and approve dihydromorphine for use alongside other analgesics. The Usenet newsgroup alt.politics.usa.legalise-dihydromorphine is one example, albeit atypical in its post volume and pattern.

Dihydromorphine was never introduced in the United States as was the case of many similar drugs invented in Europe in the intense search for stronger cough suppressants, especially to slow the spread of tuberculosis and other airborne diseases in the two decades prior to the First World War such as narcotic subject to control, and other countries' laws may vary. Its role in the production of dihydrocodeine makes it the Schedule I substance with one of the higher annual manufacturing quotas granted by the US Drug Enforcement Administration.

One scientific controversy deals with the relative strength of dihydromorphine; according to various official sources, is either 50 per cent or 115-120 per cent of the analgesic strength of morphine. Clinical experience points to the latter. In comparison, codeine in not having a ceiling effect on analgesia imposed by metabolism -- i.e., above a certain point (400 mg in most people), the codeine is wasted. Dihydromorphine has a longer duration of action (6 hours vs 4 hours for morphine).

Dihydromorphine, often labelled with the isotopes iodine-129 and buprenorphine, morphine and others are similarly used for research on the actions of drugs of this type in various systems of the body.

The human liver converts a percentage of dihydrocodeine into dihydromorphine. The liver nicocodeine to 6-nicotinoylmorphine, and so on).

Other derivates or cough suppressants (thebacon, nicocodeine, acetyldihydrocodeine, nicodicodeine, and others.)