U-47700

Also known as

Pink, pinky, U4

Classification

Opioid

Overview

This is a synthetic opioid pain medication developed as a dangerous designer drug. Since 2015, reports have surfaced of multiple deaths due to street use of U-47700 .

What does it look like?

White or light pinkish, chalky powder. It may be sold in glassine bags stamped with logos imitating heroin, in envelopes and inside knotted corners of plastic bags .

Source

Exported from illegal labs in China .

Street price

U-47700 has also been identified and sold on the Internet misleadingly as a 'research chemical' at roughly $30 per gram .

How long do its effects last?

Onset of effects

• insufflated - 5 - 20 minutes .
• oral - 15 minutes .
• insufflated/plugged - 15 minutes .
• intravenous - 0 - 1 minutes .

Peak

• insufflated - 1 - 2 hours .

Duration of effects

• insufflated - 2 - 3 hours .
• oral - 5 - 7 hours .
• insufflated/plugged - 3 - 4 hours .
• intravenous - 1 - 2 hours .

After-effects

• oral - 1 - 4 hours .
• insufflated/plugged - 1 - 4 hours .
• intravenous - 1 - 4 hours .

Pharmacology

U-47700 is selective for the µ-opioid receptor, with various sources claiming 7.5x the potency of morphine , .

Opioids exert their effects by binding to and activating the μ-opioid receptor. This occurs because opioids structurally mimic endogenous endorphins which are naturally found in the body and also work with the μ-opioid receptor set. The way in which opioids structurally mimic these natural endorphins results in their euphoria, pain relief and anxiolytic effects. This is because endorphins are responsible for reducing pain, causing sleepiness, and feelings of pleasure. They can be released in response to pain, strenuous exercise, orgasm, or general excitement.

U-47700 may also be an agonist for the kappa-opioid receptor system. As a result of this, it has become the lead compound of selective kappa-opioid receptor ligands such as U-50488 and U-69,593, which share very similar structures . Its structure led to other chemists experimenting with it to see if rigid analogs would retain activity . Although not used medically, the selective kappa ligands are used in research , .

Toxicity

U-47700 has a high toxicity relative to its dose due to its extreme potency. As with all opioids, long-term effects can vary but can include diminished libido, apathy and memory loss. It is also potentially lethal when mixed with depressants like alcohol or benzodiazepines .

Tolerance

As with other opioids, the chronic use of U-47700 can be considered moderately addictive with a high potential for abuse and is capable of causing psychological dependence among certain users. When addiction has developed, cravings and withdrawal symptoms may occur if a person suddenly stops their usage.

Tolerance to many of the effects of U-47700 develops with prolonged and repeated use. The rate at which this occurs develops at different rates for different effects, with tolerance to the constipation-inducing effects developing particularly slowly for instance. This results in users having to administer increasingly large doses to achieve the same effects. After that, it takes about 3 - 7 days for the tolerance to be reduced to half and 1 - 2 weeks to be back at baseline (in the absence of further consumption). U-47700 presents cross-tolerance with all other opioids, meaning that after the consumption of U-47700 all opioids will have a reduced effect.

It is highly advisable not to become physically dependent on this substance, as physical dependence can develop in a short period .

Effects

Physical effects

• physical euphoria,
• pupil constriction,
• appetite suppression,
• cough suppression,
• pain relief,
• respiratory depression,
• sedation,
• constipation,
• difficulty urinating,
• itchiness .

Cognitive effects

• anxiety,
• cognitive euphoria,
• compulsive redosing,
• depression,
• irritability,
• dream potentiation,
• anxiety suppression,
• cognitive fatigue,
• decreased libido,
• thought deceleration .

After-effects

• cognitive fatigue,
• thought deceleration,
• anxiety,
• depression,
• irritability .

Side-effects

• euphoria and other psychoactive effects,
• sedation, relaxation, numbness,
• potent analgesia,
• severe, possibly fatal respiration depression,
• pinpoint pupils,
• constipation,
• itching,
• drug tolerance, addiction,
• seizures,
• psychosis,
• fatal overdose .

Dangerous interactions

Although many drugs are safe on their own, they can become dangerous and even life-threatening when combined with other substances. The list below contains some common potentially dangerous combinations, but may not include all of them. Certain combinations may be safe in low doses of each but still increase the potential risk of death. Independent research should always be done to ensure that a combination of two or more substances is safe before consumption .

• Depressants (1,4-Butanediol, 2m2b, alcohol, barbiturates, benzodiazepines, GHB/GBL, methaqualone) - This combination can result in dangerous or even fatal levels of respiratory depression. These substances potentiate the muscle relaxation, sedation and amnesia caused by one another and can lead to unexpected loss of consciousness at high doses. There is also an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
• Dissociatives - This combination can result in an increased risk of vomiting during unconsciousness and death from the resulting suffocation. If this occurs, users should attempt to fall asleep in the recovery position or have a friend move them into it.
• Stimulants - It is dangerous to combine U-47700, a depressant, with stimulants due to the risk of excessive intoxication. Stimulants decrease the sedative effect of U-47700, which is the main factor most people consider when determining their level of intoxication. Once the stimulant wears off, the effects of U-47700 will be significantly increased, leading to intensified disinhibition as well as other effects. If combined, one should strictly limit themselves to only taking a certain amount of U-47700. .

Dangerous

• Ketamine - Both substances bring a risk of vomiting and unconsciousness. If the user falls unconscious while under the influence there is a severe risk of vomit aspiration if they are not placed in the recovery position.
• MXE - This combination can potentiate the effects of the opioid
• DXM - CNS depression, difficult breathing, heart issues, hepatoxic, just very unsafe combination all around. Additionally if one takes dxm, their tolerance of opiates goes down slightly, thus causing additional synergistic effects.
• Cocaine - Stimulants increase respiration rate allowing a higher dose of opiates. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.
• Alcohol - Both substances potentiate the ataxia and sedation caused by the other and can lead to unexpected loss of consciousness at high doses. Place affected patients in the recovery position to prevent vomit aspiration from excess. Memory blackouts are likely
• GHB / GBL - The two substances potentiate each other strongly and unpredictably, very rapidly leading to unconsciousness. While unconscious, vomit aspiration is a risk if not placed in the recovery position
• Tramadol - Concomitant use of tramadol increases the seizure risk in patients taking other opioids. These agents are often individually epileptogenic and may have additive effects on seizure threshold during coadministration. Central nervous system- and/or respiratory-depressant effects may be additively or synergistically present
• Benzodiazepines - Central nervous system and/or respiratory-depressant effects may be additively or synergistically present. The two substances potentiate each other strongly and unpredictably, very rapidly leading to unconsciousness. While unconscious, vomit aspiration is a risk if not placed in the recovery position Blackouts/memory loss likely .

Caution

• PCP - PCP can reduce opioid tolerance, increasing the risk of overdose
• Nitrous oxide - Both substances potentiate the ataxia and sedation caused by the other and can lead to unexpected loss of consciousness at high doses. While unconscious, vomit aspiration is a risk if not placed in the recovery position. Memory blackouts are likely.
• Amphetamines - Stimulants increase respiration rate allowing a higher dose of opiates. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.
• MAOIs - Coadministration of monoamine oxidase inhibitors (MAOIs) with certain opioids has been associated with rare reports of severe and fatal adverse reactions. There appear to be two types of interaction, an excitatory and a depressive one. Symptoms of the excitatory reaction may include agitation, headache, diaphoresis, hyperpyrexia, flushing, shivering, myoclonus, rigidity, tremor, diarrhea, hypertension, tachycardia, seizures, and coma. Death has occurred in some cases .

Withdrawal

U-47700 withdrawal symptoms can be especially painful and emerge after 2 - 4 hours after the last dose administration .

Drug testing

Currently, U-47700 is not included in standard workplace drug screens in the U.S.; however, forensics or medical laboratory testing may identify U-47700 through analytical techniques such as mass spectrometry .

=Health hazards

The DEA have reported at least 46 deaths linked to use of U-47700 that occurred in 2015 and 2016. According to the DEA, no other reports of U-47700 use in the U.S. were found prior to 2015.

In January 2017, a toxicology case report was published in the Annals of Emergency Medicine that detailed events in which fentanyl and U-47700 were being sold misleadingly as the prescription opioid pain medication Norco (acetaminophen and hydrocodone) on the streets of Northern and Central California. In one patient who presented to the emergency room, naloxone (Narcan) was administered which reversed respiratory depression and pinpoint pupils. After additional chemical analysis, it was found the "Norco" contained hydrocodone, fentanyl, and U-47700 , .

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