Abstract
Preparations containing caffeine and ephedrine have become increasingly popular among sportspersons in recent years as a means to enhance athletic performance. This is due to a slowly accumulating body of evidence suggesting that combination of the two drugs may be more efficacious than each one alone. Caffeine is a compound with documented ergogenicity in various exercise modalities, while ephedrine and related alkaloids have not been shown, as yet, to result in any significant performance improvements. Caffeine-ephedrine mixtures, however, have been reported in several instances to confer a greater ergogenic benefit than either drug by itself. Although data are limited and heterogeneous in nature to allow for reaching consensus, the increase in performance is a rather uniform finding as it has been observed during submaximal steady-state aerobic exercise, short- and long-distance running, maximal and supramaximal anaerobic cycling, as well as weight lifting. From the metabolic point of view, combined ingestion of caffeine and ephedrine has been observed to increase blood glucose and lactate concentrations during exercise, wheareas qualitatively similar effects on lipid fuels (free fatty acids and glycerol) are less pronounced. In parallel, epinephrine and dopamine concentrations are significantly increased, wheareas the effects on norepinephrine are less clear.
With respect to pulmonary gas exchange during short-term intense exercise, no physiologically significant effects have been reported following ingestion of caffeine, ephedrine or their combination. Yet, during longer and/or more demanding efforts, some sporadic enhancements have indeed been shown. On the other hand, a relatively consistent cardiovascular manifestation of the latter preparation is an increase in heart rate, in addition to that caused by exercise alone. Finally, evidence to date strongly suggests that caffeine and ephedrine combined are quite effective in decreasing the rating of perceived exertion and this seems to be independent of the type of activity being performed. In general, our knowledge and understanding of the physiological, metabolic and performance-enhancing effects of caffeine-ephedrine mixtures are still in their infancy. Research in this field is probably hampered by sound ethical concerns that preclude administration of potentially hazardous substances to human volunteers. In contrast, while it is certainly true that caffeine and especially ephedrine have been associated with several acute adverse effects on health, athletes do not seem to be concerned with these, as long as they perceive that their performance will improve. In light of the fact that caffeine and ephedra alkaloids, but not ephedrine itself, have been removed from the list of banned substances, their use in sports can be expected to rise considerably in the foreseeable future. Caffeine-ephedra mixtures may thus become one of most popular ergogenic aids in the years to come and while they may indeed prove to be one of the most effective ones, and probably one of the few legal ones, whether they also turn out to be one of the most dangerous ones awaits to be witnessed.
This is a preview of subscription content, access via your institution.









References
Applegate EA, Grivetti LE. Search for the competitive edge: a history of dietary fads and supplements. J Nutr 1997; 127 (5 Suppl.): 869S–73S
Maughan R. The athlete’s diet: nutritional goals and dietary strategies. Proc Nutr Soc 2002; 61(1): 87–96
Grivetti LE, Applegate EA. From Olympia to Atlanta: a cultural-historical perspective on diet and athletic training. J Nutr 1997; 127 (5 Suppl.): 860S–8S
Lamb DR, Knuttgen HG, Murray R, editors. Physiology and nutrition for competitive sport. Carmel (IN): Cooper Publishing Group, 1994
Lamb DR, Williams MH, editors. Ergogenics: enhancement of performance in exercise and sport. Dubuque (IA): Wm. C. Brown Publishers, 1991
Williams MH. The ergogenics edge: pushing the limits of sports performance. Champaign (IL): Human Kinetics, 1998
Bahrke MS, Yesalis CE, editors. Performance-enhancing substances in sport and exercise. Champaign (IL): Human Kinetics, 2002
Ahrendt DM. Ergogenic aids: counseling the athlete. Am Fam Physician 2001; 63(5): 913–22
Mottram DR. Banned drugs in sport: does the International Olympic Committee (IOC) list need updating? Sports Med 1999; 27(1): 1–10
Juhn M. Popular sports supplements and ergogenic aids. Sports Med 2003; 33(12): 921–39
Brice CF, Smith AP. Factors associated with caffeine consumption. Int J Food Sci Nutr 2002; 53(1): 55–64
Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med 2001; 31(11): 785–807
Melia P, Pipe A, Greenberg L. The use of anabolic-androgenic steroids by Canadian students. Clin J Sport Med 1996; 6(1): 9–14
Forman ES, Dekker AH, Javors JR, et al. High-risk behaviors in teenage male athletes. Clin J Sport Med 1995; 5(1): 36–42
Wagner JC. Enhancement of athletic performance with drugs: an overview. Sports Med 1991; 12(4): 250–65
Rogers CC. Cyclists try caffeine suppositories. Phys Sportsmed 1985; 13(3): 38–40
Nehlig A, Debry G. Caffeine and sports activity: a review. Int J Sports Med 1994; 15(5): 215–23
Associated Press. Revised banned list will be in force for Athens. ESPN Internet Ventures, 2003 [online]. Available from URL: http://espn.go.com/oly/news/2003/0917/1617822.html [Accessed 2004 Sep 14]
Jones AR, Pichot JT. Stimulant use in sports. Am J Addict 1998; 7(4): 243–55
Delbeke FT, Debackere M. Caffeine: use and abuse in sports. Int J Sports Med 1984; 5(4): 179–82
Spriet LL. Caffeine and performance. Int J Sport Nutr 1995; 5 Suppl.: S84–99
Clarkson PM. Nutrition for improved sports performance: current issues on ergogenic aids. Sports Med 1996; 21(6): 393–401
Graham TE, Spriet LL. Performance and metabolic responses to a high caffeine dose during prolonged exercise. J Appl Physiol 1991; 71(6): 2292–8
Pasman WJ, van Baak MA, Jeukendrap AE, et al. The effect of different dosages of caffeine on endurance performance time. Int J Sports Med 1995; 16(4): 225–30
Graham TE. Caffeine, coffee and ephedrine: impact on exercise performance and metabolism. Can J Appl Physiol 2001; 26 Suppl.: S103–19
Conlee RK. Amphetamine, caffeine, and cocaine. In: Lamb DR, Williams MH, editors. Ergogenics: enhancement of performance in exercise and sport. Dubuque (IA): Wm. C. Brown Publishers, 1991: 285–330
Spriet LL, Howlett RA. Caffeine. In: Maughan RJ, editor. Nutrition in sport. Oxford: Blackwell Science Ltd, 2000: 379–92
Graham TE, Spriet LL. Metabolic, catecholamine, and exercise performance responses to various doses of caffeine. J Appl Physiol 1995; 78(3): 867–74
Magkos F, Kavouras SA. Caffeine use in sports, pharmacokinetics in man, and cellular mechanisms of action. Crit Rev Food Sci Nutr. In press
Fredholm BB. On the mechanism of action of theophylline and caffeine. Acta Med Scand 1985; 217(2): 149–53
Clarkson PM, Thompson HS. Drugs and sport: research findings and limitations. Sports Med 1997; 24(6): 366–84
Dyck DJ. Dietary fat intake, supplements, and weight loss. Can J Appl Physiol 2000; 25(6): 495–523
Halpem A, Mancini MC. Treatment of obesity: an update on anti-obesity medications. Obes Rev 2003; 4(1): 25–42
Shekelle PG, Hardy ML, Morton SC, et al. Efficacy and safety of ephedra and ephedrine for weight loss and athletic performance: a meta-analysis. JAMA 2003; 289(12): 1537–45
van der Merwe PJ, Krager HS. Drags in sport: results of the past 6 years of dope testing in South Africa. S Afr Med J 1992; 82(3): 151–3
DeMeersman R, Getty D, Schaefer DC. Sympathomimetics and exercise enhancement: all in the mind? Pharmacol Biochem Behav 1987; 28(3): 361–5
Bohn AM, Khodaee M, Schwenk TL. Ephedrine and other stimulants as ergogenic aids. Curr Sports Med Rep 2003; 2(4): 220–5
Chu KS, Doherty TJ, Parise G, et al. A moderate dose of pseudoephedrine does not alter muscle contraction strength or anaerobic power. Clin J Sport Med 2002; 12(6): 387–90
Dumestre-Toulet V, Kintz P. Ephedrine abuse for doping purposes as demonstrated by hair analysis. J Anal Toxicol 2000; 24(5): 381–2
Kanayama G, Gruber AJ, Pope Jr HG, et al. Over-the-counter drug use in gymnasiums: an underrecognized substance abuse problem? Psychother Psychosom 2001; 70(3): 137–40
The NCAA Research Staff. NCAA Study of Substance Use Habits of College Student-Athletes. The National Collegiate Athletic Association Committee on Competitive Safeguards and Medical Aspects of Sports, 2001 [online]. Available from URL: http://www.ncaa.org/library/research/substance_use_habits/2001/substance_use_habits.pdf [Accessed 2004 Sep 14]
Desjardins M. Supplement use in the adolescent athlete. Curr Sports Med Rep 2002; 1(6): 369–73
Kamber M, Baume N, Saugy M, et al. Nutritional supplements as a source for positive doping cases? Int J Sport Nutr Exerc Metab 2001; 11(2): 258–63
Haller CA, Jacob III P, Benowitz NL. Pharmacology of ephedra alkaloids and caffeine after single-dose dietary supplement use. Clin Pharmacol Ther 2002; 71(6): 421–32
White LM, Gardner SF, Gurley BJ, et al. Pharmacokinetics and cardiovascular effects of ma-huang (Ephedra sínica) in normotensive adults. J Clin Pharmacol 1997; 37(2): 116–22
Gurley BJ, Gardner SF, White LM, et al. Ephedrine pharmacokinetics after the ingestion of nutritional supplements containing Ephedra sínica (ma huang). Ther Drag Monit 1998; 20(4): 439–45
Rivers WHR, Webber HN. The action of caffeine on the capacity for muscular work. J Physiol 1907; 36: 33–47
Costill DL, Dalsky GP, Fink WJ. Effects of caffeine ingestion on metabolism and exercise performance. Med Sci Sports 1978; 10(3): 155–8
Ivy JL, Costill DL, Fink WJ, et al. Influence of caffeine and carbohydrate feedings on endurance performance. Med Sci Sports 1979; 11(1): 6–11
Essig D, Costill DL, VanHandel PJ. Effects of caffeine ingestion on utilization of muscle glycogen and lipid during leg ergometer cycling. Int J Sports Med 1980; 1(1): 86–90
Spriet LL, MacLean DA, Dyck DJ, et al. Caffeine ingestion and muscle metabolism during prolonged exercise in humans. Am J Physiol 1992; 262 (6 Pt 1): E891–8
Wilcox AR. Caffeine and endurance performance. Sports Sci Exch 1990; 3(1): 1–5
Clarkson PM. Nutritional ergogenic aids: caffeine. Int J Sport Nutr 1993; 3(1): 103–11
Graham TE, Rush JW, van Soeren MH. Caffeine and exercise: metabolism and performance. Can J Appl Physiol 1994; 19(2): 111–38
Graham TE, Spriet LL. Caffeine and exercise performance. Sports Sci Exch 1996; 9(1): 1–5
Spriet LL. Ergogenic aids: recent advances and retreats. In: Lamb DR, Murray R, editors. Optimizing sport performance. Carmel (IN): Cooper Publishing Group, 1997: 185–238
Spriet LL, Graham TE. Caffeine and exercise performance. Curr Comm ACSM 1999; Jul: 1–3
Williams JH. Caffeine, neuromuscular function and high-intensity exercise performance. J Sports Med Phys Fitness 1991; 31(3): 481–9
Tarnopolsky MA. Caffeine and endurance performance. Sports Med 1994; 18(2): 109–25
Sinclair CJ, Geiger JD. Caffeine use in sports: a pharmacological review. J Sports Med Phys Fitness 2000; 40(1): 71–9
Spriet LL. Caffeine. In: Bahrke MS, Yesalis CE, editors. Performance-enhancing substances in sport and exercise. Champaign (IL): Human Kinetics, 2002: 267–78
Paluska SA. Caffeine and exercise. Curr Sports Med Rep 2003; 2(4): 213–9
Magkos F, Kavouras SA. Caffeine. In: Wolinsky I, Driskell JA, editors. Nutritional ergogenic aids. Boca Raton (FL): CRC Press, 2004: 275–323
Graham TE. The possible actions of methylxanthines on various tissues. In: Reilly T, Orme M, editors. The clinical pharmacology of sport and exercise. Amsterdam: Elsevier Science BV, 1997: 257–70
Smith DA, Perry PJ. The efficacy of ergogenic agents in athletic competition, part II: other performance-enhancing agents. Ann Pharmacother 1992; 26(5): 653–9
Bucci LR. Selected herbals and human exercise performance. Am J Clin Nutr 2000; 72 (2 Suppl.): 624S–36S
Foltz EE, Ivy AC, Barborka CJ. The influence of amphetamine (benzedrine) sulfate, d-desoxyephedrine hydrochloride (pervitin), and caffeine upon work output and recovery when rapidly exhausting work is done by trained subjects. J Lab Clin Med 1943; 28: 603–6
Sidney KH, Lefcoe NM. The effects of ephedrine on the physiological and psychological responses to submaximal and maximal exercise in man. Med Sci Sports 1977; 9(2): 95–9
Gillies H, Derman WE, Noakes TD, et al. Pseudoephedrine is without ergogenic effects during prolonged exercise. J Appl Physiol 1996; 81(6): 2611–7
Swain RA, Harsha DM, Baenziger J, et al. Do pseudoephedrine or phenylpropanolamine improve maximum oxygen uptake and time to exhaustion? Clin J Sport Med 1997; 7(3): 168–73
Walton C, Parise J, Tarnopolsky MA. The effects of pseudoephedrine on exercise performance and neuromuscular function [abstract]. Can J Appl Physiol 1997; 22 Suppl.: 63P
Gill ND, Shield A, Blazevich AJ, et al. Muscular and cardiorespiratory effects of pseudoephedrine in human athletes. Br J Clin Pharmacol 2000; 50(3): 205–13
Chester N, Reilly T, Mottram DR. Physiological, subjective and performance effects of pseudoephedrine and phenylpropanolamine during endurance running exercise. Int J Sports Med 2003; 24(1): 3–8
Bell DG, Jacobs I, Zamecnik J. Effects of caffeine, ephedrine and their combination on time to exhaustion during high-intensity exercise. Eur J Appl Physiol Occup Physiol 1998; 77(5): 427–33
Bell DG, Jacobs I, McLellan TM, et al. Reducing the dose of combined caffeine and ephedrine preserves the ergogenic effect. Aviat Space Environ Med 2000; 71(4): 415–9
Bell DG, Jacobs I. Combined caffeine and ephedrine ingestion improves run times of Canadian Forces Warrior Test. Aviat Space Environ Med 1999; 70(4): 325–9
Bell DG, McLellan TM, Sabiston CM. Effect of ingesting caffeine and ephedrine on 10-km run performance. Med Sci Sports Exerc 2002; 34(2): 344–9
Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001; 33(8): 1399–403
Jacobs I, Pasternak H, Bell DG. Effects of ephedrine, caffeine, and their combination on muscular endurance. Med Sci Sports Exerc 2003; 35(6): 987–94
Pasternak HS, Jacobs I, Bell DG. Effects of ingesting caffeine and ephedrine on muscular endurance [abstract]. Can J Appl Physiol 1999; 24(5): 471
Morton RH. Effects of caffeine, ephedrine and their combination on time to exhaustion during high-intensity exercise [letter]. Eur J Appl Physiol Occup Physiol 1999; 79(4): 379–81
Morton RH. Effects of caffeine, ephedrine and their combination on time to exhaustion during high-intensity exercise [letter]. Eur J Appl Physiol Occup Physiol 1999; 80(6): 610–2
Robertson D, Wade D, Workman R, et al. Tolerance to the humoral and hemodynamic effects of caffeine in man. J Clin Invest 1981; 67(4): 1111–7
Van Soeren MH, Graham TE. Effect of caffeine on metabolism, exercise endurance, and catecholamine responses after withdrawal. J Appl Physiol 1998; 85(4): 1493–501
Graham TE, Helge JW, MacLean DA, et al. Caffeine ingestion does not alter carbohydrate or fat metabolism in human skeletal muscle during exercise. J Physiol 2000; 529 (Pt 3): 837–47
Robertson D, Frolich JC, Carr RK, et al. Effects of caffeine on plasma renin activity, catecholamines and blood pressure. N Engl J Med 1978; 298(4): 181–6
Tarnopolsky MA, Atkinson SA, MacDougall JD, et al. Physiological responses to caffeine during endurance running in habitual caffeine users. Med Sci Sports Exerc 1989; 21(4): 418–24
Bell DG, Jacobs I, McLellan TM, et al. Thermal regulation in the heat during exercise after caffeine and ephedrine ingestion. Aviat Space Environ Med 1999; 70(6): 583–8
Bell DG, Bordeleau JMR, Jacobs I, et al. Blood pressure and heart rate after caffeine and ephedrine ingestion [abstract]. Can J Appl Physiol 1999; 24(5): 426
Bright TP, Sandage Jr BW, Fletcher HP. Selected cardiac and metabolic responses to pseudoephedrine with exercise. J Clin Pharmacol 1981; 21 (11–12 Pt 1): 488–92
Clemons JM, Crosby SL. Cardiopulmonary and subjective effects of a 60mg dose of pseudoephedrine on graded treadmill exercise. J Sports Med Phys Fitness 1993; 33(4): 405–12
Engels HJ, Wirth JC, Celik S, et al. Influence of caffeine on metabolic and cardiovascular functions during sustained light intensity cycling and at rest. Int J Sport Nutr 1999; 9(4): 361–70
Trice I, Haymes EM. Effects of caffeine ingestion on exercise-induced changes during high-intensity, intermittent exercise. Int J Sport Nutr 1995; 5(1): 37–44
Dodd SL, Brooks E, Powers SK, et al. The effects of caffeine on graded exercise performance in caffeine naive versus habituated subjects. Eur J Appl Physiol Occup Physiol 1991; 62(6): 424–9
French C, McNaughton L, Davies P, et al. Caffeine ingestion during exercise to exhaustion in elite distance runners: revision. J Sports Med Phys Fitness 1991; 31(3): 425–32
Wells CL, Schrader TA, Stern JR, et al. Physiological responses to a 20-mile run under three fluid replacement treatments. Med Sci Sports Exerc 1985; 17(3): 364–9
Casal DC, Leon AS. Failure of caffeine to affect substrate utilization during prolonged running. Med Sci Sports Exerc 1985; 17(1): 174–9
Flinn S, Gregory J, McNaughton LR, et al. Caffeine ingestion prior to incremental cycling to exhaustion in recreational cyclists. Int J Sports Med 1990; 11(3): 188–93
Titlow LW, Ishee JH, Riggs CE. Failure of caffeine to affect metabolism during 60 min submaximal exercise. J Sports Sci 1991; 9(1): 15–22
Weir J, Noakes TD, Myburgh K, et al. A high carbohydrate diet negates the metabolic effects of caffeine during exercise. Med Sci Sports Exerc 1987; 19(2): 100–5
Jacobson TL, Febbraio MA, Arkinstall MJ, et al. Effect of caffeine co-ingested with carbohydrate or fat on metabolism and performance in endurance-trained men. Exp Physiol 2001; 86(1): 137–44
Bell DG, McLellan TM. Effect of repeated caffeine ingestion on repeated exhaustive exercise endurance. Med Sci Sports Exerc 2003; 35(8): 1348–54
McNaughton LR. Two levels of caffeine ingestion on blood lactate and free fatty acid responses during incremental exercise. Res Q Exerc Sport 1987; 58: 255–9
Sasaki H, Takaoka I, Ishiko T. Effects of sucrose or caffeine ingestion on running performance and biochemical responses to endurance running. Int J Sports Med 1987; 8(3): 203–7
Bell DG, McLellan TM. Exercise endurance 1, 3, and 6h after caffeine ingestion in caffeine users and nonusers. J Appl Physiol 2002; 93(4): 1227–34
Cole KJ, Costill DL, Starling RD, et al. Effect of caffeine ingestion on perception of effort and subsequent work production. Int J Sport Nutr 1996; 6(1): 14–23
Donelly K, McNaughton L. The effects of two levels of caffeine ingestion on excess postexercise oxygen consumption in untrained women. Eur J Appl Physiol Occup Physiol 1992; 65(5): 459–63
Chad K, Quigley B. The effects of substrate utilization, manipulated by caffeine, on post-exercise oxygen consumption in untrained female subjects. Eur J Appl Physiol Occup Physiol 1989; 59(1–2): 48–54
Giles D, MacLaren D. Effects of caffeine and glucose ingestion on metabolic and respiratory functions during prolonged exercise. J Sports Sci 1984; 2: 35–46
Graham TE, Sathasivam P, MacNaughton KW. Influence of cold, exercise, and caffeine on catecholamines and metabolism in men. J Appl Physiol 1991; 70(5): 2052–8
Van Soeren MH, Sathasivam P, Spriet LL, et al. Caffeine metabolism and epinephrine responses during exercise in users and nonusers. J Appl Physiol 1993; 75(2): 805–12
Sasaki H, Maeda J, Usui S, et al. Effect of sucrose and caffeine ingestion on performance of prolonged strenuous running. Int J Sports Med 1987; 8: 261–5
Erickson MA, Schwarzkopf RJ, McKenzie RD. Effects of caffeine, fructose, and glucose ingestion on muscle glycogen utilization during exercise. Med Sci Sports Exerc 1987; 19(6): 579–83
Nehlig A, Daval JL, Debry G. Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic and psychostimulant effects. Brain Res Rev 1992; 17(2): 139–70
Fredholm BB, Battig K, Holmen J, et al. Actions of caffeine in the brain with special reference to factors that contribute to its widespread use. Pharmacol Rev 1999; 51(1): 83–133
George AJ. Central nervous system stimulants. Baillieres Best Pract Res Clin Endocrinol Metab 2000; 14(1): 79–88
Bouchard R, Weber AR, Geiger JD. Informed decision-making on sympathomimetic use in sport and health. Clin J Sport Med 2002; 12(4): 209–24
van Baak MA, Saris WH. The effect of caffeine on endurance performance after nonselective beta-adrenergic blockade. Med Sci Sports Exerc 2000; 32(2): 499–503
Cox GR, Desbrow B, Montgomery PG, et al. Effect of different protocols of caffeine intake on metabolism and endurance performance. J Appl Physiol 2002; 93(3): 990–9
Falk B, Burstein R, Ashkenazi I, et al. The effect of caffeine ingestion on physical performance after prolonged exercise. Eur J Appl Physiol Occup Physiol 1989; 59(3): 168–73
Cohen BS, Nelson AG, Prevost MC, et al. Effects of caffeine ingestion on endurance racing in heat and humidity. Eur J Appl Physiol Occup Physiol 1996; 73(3–4): 358–63
Macintosh BR, Wright BM. Caffeine ingestion and performance of a 1,500-metre swim. Can J Appl Physiol 1995; 20(2): 168–77
Dulloo AG, Seydoux J, Girardier L. Potentiation of the thermogenic antiobesity effects of ephedrine by dietary methylxanthines: adenosine antagonism or phosphodiesterase inhibition? Metabolism 1992; 41(11): 1233–41
Astrup A, Toubro S, Cannon S, et al. Thermogenic synergism between ephedrine and caffeine in healthy volunteers: a double-blind, placebo-controlled study. Metabolism 1991; 40(3): 323–9
Astrup A, Toubro S. Thermogenic, metabolic, and cardiovascular responses to ephedrine and caffeine in man. Int J Obes Relat Metab Disord 1993; 17Suppl. 1: S41–3
Davis JM, Bailey SP. Possible mechanisms of central nervous system fatigue during exercise. Med Sci Sports Exerc 1997; 29(1): 45–57
Goldberg L, Elliot D, Kuehl K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance [letter]. Med Sci Sports Exerc 2002; 34(1): 181–2
Marcus DM, Grollman AP. Ephedra-free is not danger-free [letter]. Science 2003; 301(5640): 1669–71
Landry GL. Ephedrine use is risky business. Curr Sports Med Rep 2003; 2(1): 1–2
Centers for Disease Control and Prevention (CDC). Adverse events associated with ephedrine-containing products: Texas, Dec 1993–Sep 1995. MMWR Morb Mortal Wkly Rep 1996; 45(32): 689–93
Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med 2000; 343(25): 1833–8
Josefson D. Herbal stimulant causes US deaths [letter]. BMJ 1996; 312(7043): 1378–9
Charatan F. Ephedra supplement may have contributed to sportsman’s death [letter]. BMJ 2003; 326(7387): 464
Holmgren P, Norden-Pettersson L, Ahlner J. Caffeine fatalities: four case reports. Forensic Sci Int 2004; 139(1): 71–3
Acknowledgements
No sources of funding were used to assist in the preparation of this manuscript. The authors have no conflicts of interest that are directly relevant to the content of this article.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Magkos, F., Kavouras, S.A. Caffeine and Ephedrine. Sports Med 34, 871–889 (2004). https://doi.org/10.2165/00007256-200434130-00002
Published:
Issue Date:
DOI: https://doi.org/10.2165/00007256-200434130-00002
Keywords
- Caffeine
- Maximum Voluntary Contraction
- Ephedrine
- Athletic Performance
- Pseudoephedrine