Any attempt to criminalise substances will end in the proliferation of criminal organisations
All treatment of drugs in this way causes the similar problem of black market emergence, in all circumstances. The most well know example of this is the prohibition of alcohol in the United States in early 20th century. Although prohibition was put into place to deal with excessive levels of crime and violence in society, criminal organisations took over the alcohol market and violent crime and other issues became even more frequent. Likewise, the war on drugs in many countries around the world has lead to so many uncontrollable drug problems or tragedies, and has funded crime.
Conversely it is the legalisation or decriminalisation of drugs, and treating the problem as that of a health problem, rather than a criminal one, that seems to be the most effective and have the biggest positive effect. In 2001, Portugal, a country riddled with opioid addiction, and massive nationwide drug problems, decriminalised all drugs. The drug crisis soon stabilised with dramatic falls in the level of drug use, HIV, Hepatitis, overdose, drug related crime and incarceration. This massive change is undoubtedly linked to changing drug use and possession from an arrestable offence to a finable one, and combining that with a thorough rehabilitation and support program.