TY - JOUR
T1 - Reinforcing Effects of Binary Mixtures of Common Bath Salt Constituents
T2 - Studies with 3,4-Methylenedioxypyrovalerone (MDPV), 3,4-Methylenedioxymethcathinone (methylone), and Caffeine in Rats
AU - Gannon, Brenda M.
AU - Galindo, Kayla I.
AU - Mesmin, Melson P.
AU - Rice, Kenner C.
AU - Collins, Gregory T.
N1 - Publisher Copyright:
© 2018 American College of Neuropsychopharmacology. All rights reserved.
PY - 2018/3/1
Y1 - 2018/3/1
N2 - Bath salts use is associated with high rates of abuse, toxicity, and death. Bath salt preparations often contain mixtures of drugs including multiple synthetic cathinones (eg, 3,4-methylenedioxypyrovalerone (MDPV) or 3,4-methylenedioxymethcathinone (methylone)) or synthetic cathinones and caffeine; however, little is known about whether interactions among bath salt constituents contribute to the abuse-related effects of bath salts preparations. This study used male Sprague-Dawley rats responding under a progressive ratio schedule to quantify the reinforcing effectiveness of MDPV, methylone, and caffeine, administered alone and as binary mixtures (n=12 per mixture). Each mixture was evaluated at four ratios (10: 1, 3: 1, 1: 1, and 1: 3) relative to the mean ED 50 for each drug alone. Dose-addition analyses were used to determine the predicted, additive effect for each dose pair within each drug mixture. MDPV, methylone, and caffeine maintained responding in a dose-dependent manner, with MDPV being the most potent and effective, and caffeine being the least potent and effective of the three bath salts constituents. High levels of responding were also maintained by each of the bath salts mixtures. Although the nature of the interactions tended toward additivity for most bath salts mixtures, supra-additive (3: 1 MDPV: caffeine, and 3: 1 and 1: 1 methylone: caffeine) and sub-additive (3: 1, 1: 1, and 1: 3 MDPV: methylone) interactions were also observed. Together, these findings demonstrate that the composition of bath salts preparations can have an impact on both their reinforcing potency and effectiveness, and suggest that such interactions among constituent drugs could contribute to the patterns of use and effects reported by human bath salts users.
AB - Bath salts use is associated with high rates of abuse, toxicity, and death. Bath salt preparations often contain mixtures of drugs including multiple synthetic cathinones (eg, 3,4-methylenedioxypyrovalerone (MDPV) or 3,4-methylenedioxymethcathinone (methylone)) or synthetic cathinones and caffeine; however, little is known about whether interactions among bath salt constituents contribute to the abuse-related effects of bath salts preparations. This study used male Sprague-Dawley rats responding under a progressive ratio schedule to quantify the reinforcing effectiveness of MDPV, methylone, and caffeine, administered alone and as binary mixtures (n=12 per mixture). Each mixture was evaluated at four ratios (10: 1, 3: 1, 1: 1, and 1: 3) relative to the mean ED 50 for each drug alone. Dose-addition analyses were used to determine the predicted, additive effect for each dose pair within each drug mixture. MDPV, methylone, and caffeine maintained responding in a dose-dependent manner, with MDPV being the most potent and effective, and caffeine being the least potent and effective of the three bath salts constituents. High levels of responding were also maintained by each of the bath salts mixtures. Although the nature of the interactions tended toward additivity for most bath salts mixtures, supra-additive (3: 1 MDPV: caffeine, and 3: 1 and 1: 1 methylone: caffeine) and sub-additive (3: 1, 1: 1, and 1: 3 MDPV: methylone) interactions were also observed. Together, these findings demonstrate that the composition of bath salts preparations can have an impact on both their reinforcing potency and effectiveness, and suggest that such interactions among constituent drugs could contribute to the patterns of use and effects reported by human bath salts users.
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U2 - 10.1038/npp.2017.141
DO - 10.1038/npp.2017.141
M3 - Article
C2 - 28677665
AN - SCOPUS:85041715230
SN - 0893-133X
VL - 43
SP - 761
EP - 769
JO - Neuropsychopharmacology
JF - Neuropsychopharmacology
IS - 4
ER -