Gray death is a slang term used for a potent mixture of synthetic opioids. Samples have been found to contain the designer drug U-47700, heroin, fentanyl, and carfentanil . It is taken by injection, smoking, snorting, or oral ingestion. It was first discovered in the United States and was thought to be a unique chemical compound before being identified as a mixture of drugs. In addition to containing powerful opioids, what makes gray death an extremely dangerous drug is the fact that the constituent drugs' identities, their overall ratios in the product, and their uneven distribution within the productare completely unknown to the user. This means that the user cannot predict what dose to safely take; even two identical doses by mass may contain more or less of an unknown substance due to uneven physical distribution, as seen with heroin and fentanyl mixes. Opioid addicts tend to be more susceptible to the drug . They may think they are buying heroin, unaware that it is actually gray death. Reversing a gray death overdose frequently requires multiple doses of naloxone , whereas a typical overdose of heroin (which is much less potent) typically needs only one dose. This is consistent with the difficulty of overdose reversal seen with high-affinity opioids in the fentanyl chemical family or with buprenorphine. The greater affinity of these substances for the μ-opioid receptor causes less naloxoneto bind to receptors, increasing the dosage necessary to counteract the resulting respiratory depression. The difficulty in reversing an overdose of gray death is likely due to the presence of a fentanyl analogue, which reporting seems to corroborate as of December 2018.
Gray death is a slang term which refers to a potent mixture of synthetic opioids. Samples have been found to contain heroin, fentanyl, carfentanil, and the designer drug U-47700 . It is taken by injection, smoking, snorting, or oral ingestion. The substance first appeared in America and was thought to be a unique chemical compound before being identified as a mixture of drugs. As with other illicit narcotics, gray death carries a higher risk of serious adverse effects than prescribed opioids due to the unknown and inconsistent composition of the product . As such, even experienced opioid users risk serious injury or death when taking this drug mixture. Reversing a gray death overdose may require multiple doses of naloxone . By contrast, an overdose from morphine or from high-purity heroin would ordinarily need only one dose. This difficulty is regularly encountered when treating overdoses of high-affinity opioids in the fentanyl chemical family or with buprenorphine. The greater affinity of these substances for the μ-opioid receptor impedes the activity of naloxone, which is an antagonist at the receptor. Increasing the dosage of naloxone or its frequency of administration may be required to counteract respiratory depression. 
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used for
which refers to
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the designer drug U-47700,
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and carfentanil
carfentanil, and the designer drug U-47700
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It was first discovered in the United States
The substance first appeared in America
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In addition to containing powerful opioids, what makes gray death an extremely dangerous drug is the fact that the constituent drugs' identities, their overall ratios in the product, and their uneven distribution within the productare completely unknown to the user. This means that the user cannot predict what dose to safely take; even two identical doses by mass may contain more or less of an unknown substance due to uneven physical distribution, as seen with heroin and fentanyl mixes. Opioid addicts tend to be more susceptible to the drug
As with other illicit narcotics, gray death carries a higher risk of serious adverse effects than prescribed opioids due to the unknown and inconsistent composition of the product
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They may think they are buying heroin, unaware that it is actually gray death.
As such, even experienced opioid users risk serious injury or death when taking this drug mixture.
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frequently requires
may require
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, whereas a typical overdose of heroin (which is much less potent) typically needs
. By contrast, an overdose from morphine or from high-purity heroin would ordinarily need
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is consistent with the difficulty of overdose reversal seen with
difficulty is regularly encountered when treating overdoses of
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causes less naloxoneto bind to receptors, increasing the dosage necessary to counteract the resulting
impedes the activity of naloxone, which is an antagonist at the receptor. Increasing the dosage of naloxone or its frequency of administration may be required to counteract
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The difficulty in reversing an overdose of gray death is likely due to the presence of a fentanyl analogue, which reporting seems to corroborate as of December 2018.