Types of opiates differ in a few key ways:
- What form the drugs are available in (i.e. powder or tar, pill, liquid, etc.)
- How potent they are
- How long their effects last
- Their potential for addiction
- Whether the way they are produced leads to predictable results
The production of prescription painkillers like oxycodone is regulated and therefore produces consistent effects:
- Quick, short-acting relief for less severe pain in doses as low as 5 milligrams
- Treatment of chronic and severe pain in extended release doses of over 120 milligrams.
Heroin derives from morphine but is active at lower doses, and is unregulated in the United States. Because heroin is unregulated, dose and purity vary widely, but generally doses fall within 5-200 milligrams.
Many synthetic opioids are unapproved and have very little available research on their effects in humans. What is known about some of the fentanyl analogues and other opiate-like novel psychoactive substances is that many are highly potent, with effects active at much lower doses (around 1-2 nanograms or less) than other opiates.
This is what can make synthetic opiate-laced heroin misuse more dangerous: the euphoric high that people are often seeking from heroin comes with more sedation when fentanyl is present. Therefore, people may take more than usual in pursuit of that sensation, and risk overdosing. Although this risk is present even in those with a tolerance for heroin, it is greater for opiate-naïve users.