Effects of 1,3-dimethylamylamine and caffeine alone or in combination on heart rate and blood pressure in healthy men and women.
BACKGROUND
The use of 1,3-dimethylamylamine (geranamine), alone and in combination with caffeine, is becoming widespread within the dietary supplement industry. To our knowledge, no data are available concerning the effects of oral geranamine intake on heart rate (HR) and blood pressure in individuals.


METHODS
Ten young healthy men and women ingested 1 of 5 conditions on different days using a double-blind, randomized, crossover design. The following were ingested after a 10-hour overnight fast: 250 mg caffeine (C), 50 mg geranamine (G 50 mg), 75 mg geranamine (G 75 mg), 250 mg caffeine + 50 mg geranamine (C + G 50 mg), and 250 mg caffeine + 75 mg geranamine (C + G 75 mg). Heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), and rate pressure product (RPP) were measured pre-ingestion and at 30, 60, 90, and 120 minutes post-ingestion. Plasma norepinephrine (NE) and epinephrine (EPI) were measured pre-ingestion and at 60 and 120 minutes post-ingestion.


RESULTS
Heart rate was unaffected by treatment, but blood pressure and RPP were higher with geranamine, generally in a dose-dependent manner. The peak percent change from pre-ingestion in SBP (~20%), DBP (~17%), and RPP (~9%) was noted with C + G 75 mg at 60 minutes post-ingestion. Plasma NE and EPI were relatively unaffected by treatment.


CONCLUSIONS
We report for the first time that acute ingestion of 1,3-dimethylamylamine alone and in combination with caffeine results in an increase in SBP, DBP, and RPP without an increase in HR. The largest increase is observed at 60 minutes post-ingestion of C + G 75 mg. These changes cannot be explained by circulating NE and EPI.
Department of Health and Sport Sciences, The University of Memphis, Memphis, TN, USA. rbloomer@memphis.edu
Richard J
RJ
Bloomer
Innocence C
IC
Harvey
Tyler M
TM
Farney
Zach W
ZW
Bell
Robert E
RE
Canale
D000284:Administration, Oral; D000328:Adult; D000704:Analysis of Variance; D001794:Blood Pressure / Q000187:drug effects*; D002110:Caffeine / Q000494:pharmacology*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D031315:Geranium; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D010936:Plant Extracts / Q000494:pharmacology*
D010936:Plant Extracts; D002110:Caffeine