Tuesday, April 14, 2015

On Flakka, Gravel, and Alpha-PVP

Flakka. Gravel.

No, it’s not a “new drug”.
Flakka and Gravel are generic terms that have been used to describe what is most likely the substituted cathinone, alpha-pyrrolidinopentiophenone, also known as alpha-PVP, PVP, or alpha-pyrrovalerophenone. It is most closely structurally related to the substances, prolintane (beta-ketone difference) and pyrovalerone (methyl group difference)
I covered alpha-PVP back in January 2014 here when "gravel" was a hot-topic in the media.
But, now we know more about alpha-PVP's pharmacology than we did even just over a year ago. Dr. Michael Taffe has covered these updates on alpha-PVP very well on his lab's blog, which can be found here. The Taffe Laboratory's site is also here.
Dr. Leon Gussow over at The Poison Review has also covered Flakka.
Because alpha-PVP is a rather important compound in my work in postmortem toxicology and has been associated with fatalities in the USA, I keep a list of all relevant papers/abstracts, etc. for the substance. This list is updated to April 2015.
1. H. Koppe, G. Ludwig, K. Zeile (1967) α-Pyrrolidino Ketones. United States Patent No. 3,314,970. Washington, D.C.: U.S. Patent and Trademark Office.

2. G. Gardos and J.O. Cole (1971) Evaluation of pyrovalerone in chronically fatigued volunteers. Current Therapeutic Research, Clinical and Experimental, 13: 631-635.

3. P.C. Meltzer, D. Butler, J.R. Deschamps, B.K. Madras (2006) 1-(4-methylphenyl)-2-pyrrolidin-1-yl-pentan-1-one (pyrovarlerone) analogs. A promising class of monoamine uptake inhibitors. Journal of Medicinal Chemistry, 49: 1420-1432.

4. L.R. Watterson and M. Foster Olive (2014) Synthetic cathinones and their rewarding and reinforcing effects in rodents. Advances in Neuroscience (Hindawi), 4: 209875

5. A.Kaizaki, S. Tanaka, S. Numazawa (2014) New recreational drug 1-phenyl-2-(1-pyrrolidinyl)-1-pentanone (alpha-PVP) activates central nervous system via dopaminergic neuron. The Journal of Toxicological Sciences, 39: 1-6.

6. K.G. Shanks, T. Dahn, G. Behonick, A. Terrell (2012) Analysis of first and second generation legal highs for synthetic cannabinoids and synthetic stimulants by ultra-performance liquid chromatography and time of flight mass spectrometry. Journal of Analytical Toxicology, 36: 360-371.

7. L.R. Watterson, B.T. Burrows, R.D. Hernandez, K.N. Moore, M. Grabenauer, J.A. Marusich, M.F. Olive (2014) Effects of α-pyrrolidinopentiophenone and 4-methyl-N-ethylcathinone, two synthetic cathinones commonly found in second-generation “bath salts”, on intracranial self-stimulation thresholds in rats. International Journal of Neuropsychopharmacology, 18.

8. J.A. Marusich, K.R. Antonazzo, J.L. Wiley, B.E. Blough, J.S. Partilla, M.H. Baumann (2014) Pharmacology of novel synthetic stimulants structurally related to the“bath salts” constituent, 3,4-methylenedioxypyrovarlerone (MDPV). Neuropharmacology, 87: 206-213.

9. J.E. Naylor, K.B. Freeman, B.E. Blough, W.L. Wooverton, S.L. Huskinson (2015) Discriminative-stimulus effects of second generation synthetic cathinones in methamphetamine-trained rats. Drug and Alcohol Dependence, 149: 280-284.

10. C. Sauer, F.T. Peters, C. Haas, M.R. Meyer, G. Fritschi, H.H. Mauer (2009) New designer drug alpha-pyrrolidinovalerophenone (PVP): studies on its metabolism and toxicological detection in rat urine using gas chromatographic/mass spectrometric techniques. Journal of Mass Spectrometry, 44: 952-964.

11. E. Tyrkko, A. Pelander, R.A. Ketola, I. Ojanpera (2013) In silico and in vitro metabolism studies support identification of designer drugs in human urine by liquid chromatography/quadrupole-time-of-flight mass spectrometry. Analytical and Bioanalytical Chemistry, 405: 6697-6709.

12. V. Uralets, S. Rana, S. Morgan, W. Ross (2014) Testing for designer stimulants: metabolic profiles of 16 synthetic cathinones excreted free in human urine. Journal of Analytical Toxicology, 38: 233-241.

13. Drug Enforcement Administration, Department of Justice (2014) Schedules of controlled substances: temporary placement of 10 synthetic cathinones into Schedule I. Final order. Federal Register, 79: 12938-12943.

14. A.M. Leffler, P.B. Smith, A. de Armas, F.L. Dorman (2014) The analytical investigation of synthetic street drugs containing cathinone analogs. Forensic Science International, 234: 50-56.

15. F. Dragogna, L. Oldani, M. Buoli, A.C. Altamura (2014) A case of severe psychosis induced by novel recreational drugs. F1000Research,3: 21.

16. J.L. Knoy, B.L. Peterson, F.J. Couper (2014) Suspected impaired driving case involvingα-ppyrrolidinovalerophenone, methylone, and ethylone. Journal of Analytical Toxicology, 38: 615-617.

17. L.J. Marinetti and H.M. Antonides (2013) Analysis of synthetic cathinones commonly found in bath salts in human performance and postmortem toxicology: method development, drug distribution and interpretation of results. Journal of Analytical Toxicology, 37: 135-146.

18. L.L. Richards-Waugh, K.M. Bailey, D.J. Clay, M.A. Gebhardt, C.L. Newsome-Sparks, H.E. Mahmoud, S.E. Venuti, J.C. Kraner (2013) Deaths involving the recreational use of α-PVP (α-pyrrolidinopentiophenone). K16. Proceedings of the American Academy of Forensic Sciences. http://www.aafs.org/sites/default/files/pdf/ProceedingsWashingtonDC2013.pdf

19. K.G. Shanks, G.S. Behonick, A.R. Terrell (2013) Detection of Alpha-PVP in Postmortem Blood Casework by UPLC/MS/MS. P12. Proceedings of the Society of Forensic Toxicologists

20. K.W. Simonsen, H.M. Edvardsen, G. Thelander, I. Ojanpera, S. Thordardottir, L.V. Andersen, P. Krikku, V. Vindenes, D. Christoffersen, G.J. Delaveris, J. Frost (2015) Fatal poisoning in drug addicts in the Nordic countries in 2012. Forensic Science International, 248: 172-180.

21. H. Nagai, K. Saka, M. Nakajima, H. Maeda, R. Kuroda, A. Igarashi, T. Tsujimura-Ito, A. Nara, M. Komori, K. Yoshida (2014) Sudden death after sustained restraint following self-administration of the designer drug α-pyrrolidinovalerophenone. International Journal of Cardiology, 172: 263-265.

22. K. Sellors, A. Jones, B. Chan (2014) Death due to intravenous use ofα-pyrrolidinopentiophenone. Medical Journal of Australia, 201: 601-603.

23. M. Skykutera, M. Cychowska, E. Bloch-Boguslawska (2015) A fatal case of pentedrone and α-pyrrolidinovalerphenone poisoning. Journal of Analytical Toxicology. Manuscript in Press.

If you know of a paper or abstract that includes alpha-PVP that I have missed, please send it to me or leave the citation in the comments and I can add it to the list.


  1. Thanks for the links and for creating this handy bibliography.

  2. HI you have a good blog i like your blog as it have all the good information. for much more information Click on buy a-PVP

  3. what kind of moron would get hi on this garbage?