biostudies-literatureStein JSNIDA NIH HHSNational Institute on Drug Abusee70056https://www.ebi.ac.uk/biostudies/studies/S-EPMC12503084biostudies-literatureUnknown124(3)Using the Experimental Tobacco Marketplace, we examined the effects of e-liquid freebase nicotine strength (3-24 mg/mL) and e-liquid price (US$0.25-$1.00/mL) on behavioral economic substitution for cigarettes in dual cigarette/e-cigarette (n = 41) and exclusive cigarette (n = 40) users. Subjective effects of nicotine strength were also examined. All nicotine strengths served as a substitute for combustible cigarettes, with greater substitution observed in dual users. When analyzing e-liquid volume purchased (mL), nicotine strength did not influence substitution; however, when analyzing e-liquid nicotine purchased (mg), degree of substitution increased as a function of nicotine strength. Additionally, higher nicotine strengths reduced the volume and probability of e-liquid purchasing, increJournal of the experimental analysis of behaviorDoes e-cigarette nicotine strength influence substitution for combustible cigarettes?PMC12503084R21 DA0463395R21DA046339Brown JMStein JSCurran KMTegge ANBickel WKfalseDoes e-cigarette nicotine strength influence substitution for combustible cigarettes?Using the Experimental Tobacco Marketplace, we examined the effects of e-liquid freebase nicotine strength (3-24 mg/mL) and e-liquid price (US$0.25-$1.00/mL) on behavioral economic substitution for cigarettes in dual cigarette/e-cigarette (n = 41) and exclusive cigarette (n = 40) users. Subjective effects of nicotine strength were also examined. All nicotine strengths served as a substitute for combustible cigarettes, with greater substitution observed in dual users. When analyzing e-liquid volume purchased (mL), nicotine strength did not influence substitution; however, when analyzing e-liquid nicotine purchased (mg), degree of substitution increased as a function of nicotine strength. Additionally, higher nicotine strengths reduced the volume and probability of e-liquid purchasing, incre2025-01-01T00:00:00Z2025 Nov2026-07-15T07:34:02.989Z2026-07-02T03:08:41.275ZS-EPMC125030844105589310.1002/jeab.70056