|Summary sheet: Dextropropoxyphene
|Dextropropoxyphene, Propoxyphene, Darvon
|Routes of Administration
Dextropropoxyphene (also known as Propoxyphene and Darvon) is a synthetic opioid of the phenylpropylamine chemical class. Like other substances in its class, particularly tapentadol and tramadol, it produces mild euphoric, analgesic, sedative and antitussive effects when administered (typically orally, but sometimes intravenous or rectally). Notably, it is reported to produce significantly less euphoria in comparison to other opioids.
Dextropropoxyphene was first patented in 1955 and subsequently manufactured by Eli Lilly and Company.
Due to its euphoric and analgesic effects, dextropropoxyphene is known to be habit forming, albeit not to the same extent as other opioids such as morphine or heroin. Notably, dextropropoxyphene is also known to cause seizures and potentially fatal cardiac arrhythmia at high doses, which are not able to be reversed by naloxone.
Today, dextropropoxyphene is rarely encountered on the streets and is sometimes obtained by prescription from a compounding pharmacy. It is strongly recommended that one research this substance's toxicity and use proper harm reduction practices if choosing to use this substance.
Dextropropoxyphene is similar in structure to tapentadol. While tapentadol has an ethyl substitution on the gamma-carbon, dextropropoxyphene instead has both benzyl and propionyl substitutions. Dextropropoxyphene also contains a benzene ring in place of the phenol ring found in tapentadol. The empirical formula of dextropropoxyphene is C22H29NO2 and has a molar mass of 339.471 grams per mole.
Opioids produce their effects by binding to and activating the μ-opioid receptor. This occurs because opioids structurally mimic endogenous endorphins which are naturally found within the body and also work upon 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.
Unlike most opioids, dextropropoxyphene is also a weak serotonin reuptake inhibitor as well as a potent nicotinic acetylcholine antagonist. Dextropropoxyphene has a bioavailability of about 40% and is metabolized by the cytochrome P450 3A4 enzyme. The optical isomer of dextropropoxyphene, levopropoxyphene has no analgesic activity but retains antitussive effects.
Disclaimer: The effects listed below cite the Subjective Effect Index (SEI), an open research literature based on anecdotal user reports and the personal analyses of PsychonautWiki contributors. As a result, they should be viewed with a healthy degree of skepticism.
It is also worth noting that these effects will not necessarily occur in a predictable or reliable manner, although higher doses are more liable to induce the full spectrum of effects. Likewise, adverse effects become increasingly likely with higher doses and may include addiction, severe injury, or death ☠.
The general sensation of dextropropoxyphene can be described as one of euphoria, relaxation, anxiety suppression and pain relief.
- Pain relief - This effect is less intense than that of other opioids such as morphine and fentanyl.
- Physical euphoria - This particular substance can be considered as less intense in its physical euphoria when compared with that of morphine or diacetylmorphine (heroin). The sensation itself can be described as extreme feelings of intense physical comfort, warmth, love and bliss.
- Respiratory depression - At low to moderate doses, this effect results in the sensation that the breath is slowed down mildly to moderately, but does not cause noticeable impairment. At high doses and overdoses, opioid-induced respiratory depression can result in a shortness of breath, abnormal breathing patterns, semi-consciousness, or unconsciousness. Severe overdoses can result in a coma or death without immediate medical attention.
- Cough suppression
- Difficulty urinating
- Pupil constriction
- Decreased libido
- Appetite suppression
- Dizziness - Dextropropoxyphene causes dizziness at a higher rate than other opioids.
- Orgasm suppression
- Cognitive euphoria - This particular substance can be considered as less intense in its cognitive euphoria when compared with that of morphine or diacetylmorphine (heroin). The sensation itself can be described as powerful and overwhelming feeling of emotional bliss, contentment, and happiness.
- Anxiety suppression
- Compulsive redosing
- Confusion - Dextropropoxyphene may cause confusion at a higher rate than other opioids.
- Dream potentiation
There are currently no anecdotal reports which describe the effects of this compound within our experience index. Additional experience reports can be found here:
Toxicity and harm potential
Dextropropoxyphene has a high toxicity relative to dose. 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 and generally has a wider range of substances which it is dangerous to combine with in comparison to other opioids. Dextropropoxyphene is known to lower the seizure threshold. It should not be taken during benzodiazepine withdrawals as this can potentially cause seizures. Dextropropoxyphene is known to cause potentially fatal heart arrhythmias, and it is discouraged to take in very heavy doses or several days in a row.
It is strongly recommended that one use harm reduction practices when using this drug.
Tolerance and addiction potential
As with other opioids, the chronic use of dextropropoxyphene 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 dextropropoxyphene 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). Dextropropoxyphene presents cross-tolerance with all other opioids, meaning that after the consumption of dextropropoxyphene all opioids will have a reduced effect.
Warning: Many psychoactive substances that are reasonably safe to use on their own can suddenly become dangerous and even life-threatening when combined with certain other substances. The following list provides some known dangerous interactions (although it is not guaranteed to include all of them).
Always conduct independent research (e.g. Google, DuckDuckGo, PubMed) to ensure that a combination of two or more substances is safe to consume. Some of the listed interactions have been sourced from TripSit.
- 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
- Amphetamines - Stimulants increase respiration rate which allows for a higher dose of opiates than would otherwise be used. If the stimulant wears off first then the opiate may overcome the user and cause respiratory arrest.
- 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.
- Cocaine - Stimulants increase respiration rate, which allows for a higher dose of opiates than would otherwise be used. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.
- DXM - Generally considered to be toxic. CNS depression, difficulty breathing, heart issues, and liver toxicity have been observed. Additionally if one takes DXM, their tolerance of opiates goes down slightly, thus causing additional synergistic effects.
- 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
- 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.
- MAOIs - Coadministration of monoamine oxidase inhibitors (MAOIs) with certain opioids has been associated with rare reports of severe 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.
- MXE - MXE can potentiate the effects of opioids but also increases the risk of respiratory depression and organ toxicity.
- Nitrous - 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 common.
- PCP - PCP may reduce opioid tolerance, increasing the risk of overdose.
- Tramadol - Increased risk of seizures. Tramadol itself is known to induce seizures and it may have additive effects on seizure threshold with other opioids. Central nervous system- and/or respiratory-depressant effects may be additively or synergistically present.
- Grapefruit - While grapefruit is not psychoactive, it may affect the metabolism of certain opioids. Tramadol, oxycodone, and fentanyl are all primarily metabolized by the enzyme CYP3A4, which is potently inhibited by grapefruit juice. This may cause the drug to take longer to clear from the body. it may increase toxicity with repeated doses. Methadone may also be affected. Codeine and hydrocodone are metabolized by CYP2D6. People who are on medicines that inhibit CYP2D6, or that lack the enzyme due to a genetic mutation will not respond to codeine as it can not be metabolized into its active product: morphine.
Serotonin syndrome risk
- MAOIs - Such as banisteriopsis caapi, syrian rue, phenelzine, selegiline, and moclobemide.
- Serotonin releasers - Such as MDMA, 4-FA, methamphetamine, methylone and αMT.
- SSRIs - Such as citalopram and sertraline
- SNRIs - Such as tramadol and venlafaxine
- Germany: Dextropropoxyphene is controlled under BtMG Anlage II, making it illegal to manufacture, import, possess, sell, or transfer it without a license.
- Russia: Dextropropoxyphene is a Schedule II controlled substance.
- Switzerland: Dextropropoxyphene is a controlled substance specifically named under Verzeichnis A. Medicinal use is permitted. Some preparations containing Dextropropoxyphene are included in Verzechnis C, while certain ones are excluded.
- United Kingdom: Dextropropoxyphene is a Class C, Schedule 2 or Schedule 5 substance depending on the dose.
- United States: Dextropropoxyphene is a Schedule II or Schedule IV Controlled Substance depending on the dosage and other ingredients. Dextropropoxyphene has been withdrawn in the United States and is no longer available through prescription, although it is possible some compounding pharmacies may still carry it.
- Risks of Combining Depressants - TripSit
- Xiao, Y., Smith, R. D., Caruso, F. S., Kellar, K. J. (1 October 2001). "Blockade of Rat α3β4 Nicotinic Receptor Function by Methadone, Its Metabolites, and Structural Analogs". Journal of Pharmacology and Experimental Therapeutics. 299 (1): 366–371. ISSN 0022-3565.
- Ershad, M., Cruz, M. D., Mostafa, A., Mckeever, R., Vearrier, D., Greenberg, M. I. (March 2020). "Opioid Toxidrome Following Grapefruit Juice Consumption in the Setting of Methadone Maintenance". Journal of Addiction Medicine. 14 (2): 172–174. doi:10.1097/ADM.0000000000000535. ISSN 1932-0620.
- Gillman, P. K. (2005). "Monoamine oxidase inhibitors, opioid analgesics and serotonin toxicity". British Journal of Anaesthesia. 95 (4): 434–441. doi: . eISSN 1471-6771. ISSN 0007-0912. OCLC 01537271. PMID 16051647.
- Anlage II BtMG - Einzelnorm
- Постановление Правительства РФ от 01.10.2012 N 1002 (ред. от 09.08.2019)
- "Verordnung des EDI über die Verzeichnisse der Betäubungsmittel, psychotropen Stoffe, Vorläuferstoffe und Hilfschemikalien" (in German). Bundeskanzlei [Federal Chancellery of Switzerland]. Retrieved January 1, 2020.
- List of most commonly encountered drugs currently controlled under the misuse of drugs legislation
- DEA Controlled Drugs | https://www.deadiversion.usdoj.gov/schedules/orangebook/e_cs_sched.pdf