Desomorphine is an opioid analogue and morphine derivative in which the 6-hydroxyl group and the double bond at carbons 7 and 8 of morphine are reduced. Desomorphine can cross the blood - brain barrier, binding to opioid receptors, similar to the pharmacokinetic distribution of all phenanthrene-structured alkaloids.

Taking Desomorphine causes euphoria as well as sedative and analgesic relief. In addition to its faster onset than other powerful painkillers drugs such as morphine, desomorphine also initiates less sedative effects and seems to have favorable postoperative results, such as reduced need for catheterization, less dizziness, and decreased vomiting incidence. In comparison with Morphine, Desomorphine is faster reduced. It follows that it has to be taken it more frequently to get the same effects. Furthermore, it causes side effects such as respiratory and gastrointestinal problems and increased blood pressure. In addition, Desomorphine's withdrawal symptoms are up to three times longer than Morphine's. This leads to the conclusion that Desomorphine is more addictive. At present, desomorphine is classified as a narcotic drug (DEA code number 9055) in Schedule I of the U.S. Controlled Substances Act and is listed as a controlled substance under the international Single Convention on Narcotic Drugs of 1961.

Desomorphine:
https://drugs.ncats.io/drug/7OP86J5E33

Developed by Roche in the 1930s, It was originally synthesized with the intention to create an alternative to morphine in terms of tolerance and addiction properties and improve the side effect profile. However, desomorphine fell short of these expectations and showed an increased dependence potential compared with morphine. Desomorphine first saw use in Switzerland under the trade name Permonid. It was described as having a fast onset, a short duration of action, relatively little nausea, and analgesic potency 8 to 10 times higher than morphine. It was used predominantly for postoperative pain due to its fast onset of action and reduced the tendency to cause respiratory depression and nausea. Concerns about its dependence and abuse potential stemming from these properties led it to fall out of clinical use. Desomorphine first emerged in the Russian drug scene around 2003 under the term Krokodil.

The name is a reference to the scaly, green-black skin discoloration frequently noted in its users. Its name is derived from crocodile (krokodil in Russian).

Its use and prevalence has been attributed to widespread availability of codeine tablets as inexpensive over-the-counter drugs, along with a simple production process that can be done in a kitchen laboratory using iodine, red phosphorus, paint thinner, and hydrochloric acid. The application of krokodil regularly induces immediate damage to blood vessels, muscles, and bone and can induce multiple organ failure. These severe complications are, however, caused by the toxic byproducts of the home production process rather than desomorphine itself.

It should be noted that the scientific coverage of Krokodil is lacking and most of the knowledge concerning krokodil is based on media coverage. A small number of cases involving krokodil use outside of Russia, including Germany and the United States, have been reported but have failed to be substantiated. As of 2018, the only confirmed reports of krokodil use are from Russia.

Excerpt from psychonautwiki.org:
https://psychonautwiki.org/wiki/Desomorphine

Krokodil, or desomorphine, is a cheap heroin substitute. You get it by mixing codeine with paint thinner, gasoline, and several other toxic ingredients. The drug first popped up in Eastern Europe early last decade, and appears to be relatively popular in Russia. Krokodil is unquestionably bad for your health: Regular users can expect to live an average of just a couple years after they start taking the drug, and that short lifespan will be plagued by painful sores and skin ulcers, internal vein and tissue damage, and organ failure.

It's been hard to miss the stories about the rise of "krokodil," a dangerous drug with which American journalists have become fascinated, thanks to its relevance to two of the media's favorite topics: zombie culture and the strange things that our children do behind our backs. Like most stories about drug panics the reporting on the ostensibly "flesh-eating" krokodil generally contains an ounce of truth and pounds of utter nonsense. Yes, krokodil is here, and yes, it is very bad for you. No, it isn't everywhere. No, it doesn't turn users into the walking dead. It poses no immediate danger to your children, unless they are prone to headaches caused by bombastic headlines. And while claims that krokodil is spreading rapidly throughout the U.S. might be excellent clickbait, they do not stand up to serious scrutiny.

Excerpt from slate.com:
https://slate.com/news-and-politics/2013/11/krokodil-desomorphine-dont-believe-the-hype-about-flesh-eating-drug-krokodil.html/

Krokodil, a cheap substitute for heroin, was one of the deadliest designer drugs ever to sweep through Russia. Appearing on the black market in the early 2000s, it wound up ensnaring hundreds of thousands of addicts across the country, and it spread especially fast in poor, industrial areas like Uralmash. Its appeal was simple: addicts could easily learn to cook it in their kitchens using ingredients purchased at local pharmacies and hardware stores, among them hydrochloric acid, paint thinner and red phosphorous, which they scraped from the sides of match boxes. For a fraction of the price of heroin, the drug produced a similar high and was just as addictive.

But the damage it caused was far more gruesome and often irreversible. The addict's flesh at the injection site would often rot away, while the tissues of the brain and other vital organs were severely eroded. Addicts pay dearly for krokodil's cheap high. Wherever on the body a user injects the drug, blood vessels burst and surrounding tissue dies, sometimes falling off the bone in chunks. That side effect has earned krokodil its other nickname: the zombie drug. The typical life span of an addict is just two or three years.

Excerpt from time.com:
http://time.com/4358805/krokodil-deadliest-drug-legacy/

Derivative of codeine:

What is krokodil (desomorphine)?
Desomorphine, known by the street name krokodil, is an opioid derivative of codeine. Like heroin and other opioids, it has a sedative and analgesic effect and is highly addictive. Krokodil is reported to contain desomorphine, a synthetic morphine analogue synthesized in the 1930s. Due to illicit, home-based manufacturing it may contain other unknown ingredients. It is typically abused via the intravenous route. Homemade versions of the drug start with codeine, and can be 'cooked' similar to illicit methamphetamine ("meth") production. According to reports, the drug is fast-acting within 2 to 3 minutes and 10 to 15 times more potent than morphine, and three times as toxic. In fact, when the toxic chemicals are removed, quite often what is left is desomorphine, a compound very similar to heroin. After a rapid onset, the euphoric effects may last less than two hours. Due to the short duration of the "high", many users find themselves in a rapid repetition of drug use to avoid withdrawal symptoms that resemble heroin. Due to the drug's rapid onset but short duration of action and frequent administration, quick physical dependence may occur.

Some of the side effects:
There have been multiple unconfirmed news reports of users in the U.S. who have had extreme skin ulcerations, infections and scale-like skin due to use of krokodil. Krokodil has been synthesized in Russia for over a decade. About one million people in Russia use krokodil according to the New York State Office of Alcoholism and Substance Abuse Services. Krokodil goes by the names of "Cheornaya" in Russia and "Himiya" in Ukraine. Previously in Russia and Ukraine, Afghan heroin was the drug of choice when making homemade injectables. Due to a possible Afghan opium crop fungal disease in 2010, the production of opium was 48 percent lower than the previous year. Therefore, in Eurasia, users turned to over-the-counter medications that contain codeine for pain or cough (e.g. Solpadeine, Codterpin or Codelac) as an ingredient for krokodil. Codeine is preferred instead of heroin because of lower costs and ease of availability.

Addiction:
Is krokodil addictive?
Addiction is an obvious problem with krokodil use due to its high opioid potency and short duration of effect. Frequent administration may lead to binge patterns that can last for days. Users are at increased risk for exhaustion due to sleep deprivation, memory loss, and problems with speech. Variations in potency or "homemade" recipes can put users at increased risk of overdose.

According the the DEA, repeated administration of desomorphine with short intervals in cancer patients with severe pain showed that desomorphine produced a high degree of addiction liability.

Another less obvious risk with krokodil use is that those who are afflicted with gangrene and other side effects may delay seeking much-needed medical treatment due to fear of legal action. In addition, the desire for continued krokodil administration to prevent withdrawal effects may prevent users from finding treatment.

Drugs.com Krokodil Drug Facts:
https://www.drugs.com/illicit/krokodil.html

DEA 1 page PDF:
https://www.deadiversion.usdoj.gov/drug_chem_info/desomorphine.pdf

Desomorphine:

Dose-by-dose it is eight to ten times more potent than morphine

• A semi-synthetic opioid
• Powerful, fast-acting effects, such as sedation and analgesia
• Discovered and patented in Germany in 1920 but was not generally recognized
• It was later synthesized in 1932
• Patented it in 1934 in the United States

In Russia, desomorphine was declared an illegal narcotic analgesic in 1998. However, while codeine containing drugs generally have been prescription products in Europe, in Russia they were sold freely over-the-counter until June 2012. The number of users in Russia was estimated to have reached around one million at the peak of the drug's popularity.

Also known by: dihydrodesoxymorphine, its former brand name Permonid and the street name krokodil or crocodil. Colloquially called the zombie drug.

Desomorphine was used in Switzerland for the treatment of severe pain under the brand name Permonid and was described as having a fast onset and a short duration of action, with relatively little nausea compared to equivalent doses of morphine.

Desomorphine abuse in Russia attracted international attention in 2010 due to an increase in clandestine production, presumably due to its relatively simple synthesis from codeine available over-the-counter. Abuse of homemade desomorphine was first reported in Siberia in 2003 when Russia started a major crackdown on heroin production and trafficking, but has since spread throughout Russia and the neighboring former Soviet republics.

The drug can be made from codeine and iodine derived from over-the-counter medications and red phosphorus from match strikers

Illicitly produced desomorphine is typically far from pure and often contains large amounts of toxic substances and contaminants as a result of the drug producers neglecting to remove highly toxic reactants and solvents left over from synthesis.