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Research Articles
Ephedra/Ephedrine
www.ephedrafacts.com
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Int J Obes Relat
Metab Disord 2001 Mar;25(3):316-24 |
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An
herbal supplement containing Ma Huang-Guarana for weight loss: a
randomized, double-blind trial.
Boozer CN, Nasser JA, Heymsfield SB, Wang V, Chen G, Solomon JL.
Obesity Research Center, St Luke's-Roosevelt Hospital Center and
Department of Medicine, Columbia University College of Physicians
and Surgeons, New York 10025, USA.
cnb7@columbia.edu
OBJECTIVE: To examine in overweight humans the short-term safety and
efficacy for weight loss of an herbal supplement containing Ma
Huang, Guarana and other ingredients. DESIGN: An 8 week randomized,
double-blind placebo controlled study of a herbal dietary supplement
(72 mg/day ephedrine alkaloids and 240 mg/day caffeine). SUBJECTS:
Overweight men and women (body mass index, > or =29 and < or =35
kg/m2). MEASUREMENTS: The primary outcome variable was body weight
change. Secondary variables included anthropometric, metabolic and
cardiovascular changes. RESULTS: Sixty-seven subjects were
randomized to either placebo (n=32) or active Ma Huang/Guarana
(n=35). Twenty-four subjects in each group completed the study.
Active treatment produced significantly (P<0.006) greater loss of
weight (X+/-s.d.,-4.0+/-3.4 kg) and fat (-2.1+/-3.0% fat) over the
8-week treatment period than did placebo (-0.8+/-2.4 kg and
0.2+/-2.3% fat). Active treatment also produced greater reductions
in hip circumference and serum triglyceride levels. Eight of the 35
actively treated subjects (23%) and none of the 32 placebo-treated
control subjects withdrew from the protocol because of potential
treatment-related effects. Dry mouth, insomnia and headache were the
adverse symptoms reported most frequently by the herbal vs placebo
group at the final evaluation visit. CONCLUSIONS: This herbal
mixture of Ma Huang and Guarana effectively promoted short-term
weight and fat loss. Safety with long-term use requires further
investigation.
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Int J Obes Relat
Metab Disord 1993 Dec;17 Suppl 3:S73-7; discussion S82 |
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The
acute and chronic effects of ephedrine/caffeine mixtures on energy
expenditure and glucose metabolism in humans.
Toubro S, Astrup A, Breum L, Quaade F.
Research Department of Human Nutrition, Royal Veterinary and
Agricultural University, Fredriksberg,
Copenhagen,
Denmark.
This paper describes a 24-week open follow-up trial with reduced
obese patients all receiving an ephedrine/caffeine combination (20
mg/200 mg) three times a day. The study was a continuation of a
previous 24-week double-blind placebo-controlled study where the
ephedrine/caffeine mixture had shown superior weight-reducing
properties when compared with either ephedrine alone (20 mg) or
caffeine alone (200 mg) three times a day. The medication was
stopped between weeks 24-26 in order to evaluate withdrawal
symptoms. The follow-up period was from weeks 26 to 50. Of 127
patients included, 99 completed the follow-up treatment, which
resulted in an additional weight loss of 1.1 kg (P = 0.02). Adverse
drug reactions were all minor and temporary. We conclude that the
ephedrine/caffeine combination is safe and effective in long-term
treatment in improving and maintaining weight loss. The side-effects
are minor and transient and no clinically relevant withdrawal
symptoms have been observed.
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Int J Obes Relat
Metab Disord 1993 Jul;17(7):383-90 |
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Effect
of physical training on thermogenic responses to cold and ephedrine
in obesity.
Nielsen B, Astrup A, Samuelsen P, Wengholt H,
Christensen NJ.
August Krogh Institute,
University of
Copenhagen,
Denmark.
The metabolic response to two tests: ephedrine and cooling in water
at 15 degrees, was measured in eight obese and 13 normal weight
persons matched for age and body height. The increase in heat
production caused by ephedrine was significantly lower in the obese
subjects than in the normal weight subjects. Also a 0.3 degree C
degree fall in tympanic temperature during cold exposure induced a
significantly smaller increase in energy expenditure and a reduced
plasma noradrenaline response in the obese subjects. Six obese and
six normal weight persons performed aerobic bicycle training for
five weeks, and the tests were repeated. Bicycle ergometer training
for one hour per day (heart rate 140-160 bpm) for five weeks
increased the maximal oxygen uptake by 13% and 12% (P < 0.05) in the
obese and the normal weight subjects, respectively. After training,
the responses of the obese to ephedrine tended to increase, whereas
no significant improvement in their cold-induced thermogenesis was
found. The study shows that obese subjects have a decreased
thermogenic response to sympathomimetic stimulation and to cold
exposure, which was only slightly improved by endurance training.
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Int J Obes Relat
Metab Disord 1993 Feb;17 Suppl 1:S69-72 |
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Safety and efficacy of long-term treatment with
ephedrine, caffeine and an ephedrine/caffeine mixture.
Toubro S, Astrup AV, Breum L, Quaade F.
Research Department of Human Nutrition, Royal Veterinary and
Agricultural University, Fredriksberg,
Copenhagen,
Denmark.
In a randomized, placebo-controlled, double blind study, 180 obese
patients were treated by diet (4.2 MJ/day) and either an
ephedrine/caffeine combination (20mg/200mg), ephedrine (20mg),
caffeine (200mg) or placebo 3 times a day for 24 weeks. 141 patients
completed this part of the study. All medication was stopped between
week 24-26 in order to catch any withdrawal symptoms. From week 26
to 50, 99 patients completed treatment with the ephedrine/caffeine
compound in an open trial design, resulting in a statistically
significant (p = 0.02) weight loss of 1.1kg. In another randomized,
double-blind, placebo-controlled 8 week study on obese subjects we
found the mentioned compound showed lean body mass conserving
properties. We conclude that the ephedrine/caffeine combination is
effective in improving and maintaining weight loss, further it has
lean body mass saving properties. The side effects are minor and
transient and no withdrawal symptoms have been found.
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Int J Obes Relat
Metab Disord 1993 Feb;17 Suppl 1:S41-3 |
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Thermogenic, metabolic, and cardiovascular responses to ephedrine
and caffeine in man.
Astrup A, Toubro S.
Research Department of Human Nutrition, Royal Veterinary and
Agricultural University,
Copenhagen,
Denmark.
To develop an appropriate combination of ephedrine and caffeine
consisting of clinically relevant doses, we examined the acute
thermogenic, metabolic, and cardiovascular effects of different
doses of caffeine (C) and ephedrine (E) given separately and in
combination to normal subjects. The thermogenic effect after E+C (20
mg/200mg) was larger than that of any other combinations, and E and
C exerted a supra-additive synergism on thermogenesis and systolic
blood pressure, while being without effect on diastolic blood
pressure. The combination also had pronounced effects on glucose
metabolism by increasing plasma glucose, insulin and C-peptide
concentrations. During chronic treatment the effect of E+C on energy
expenditure is maintained, while side effects subside because
tolerance develops to its hemodynamic and metabolic effects. During
dietary energy restriction E+C promotes fat loss and preserves
fat-free mass, which may contribute to its chronic effect on energy
balance. In conclusion, the hemodynamic and side effects to E+C are
transient during chronic treatment, while the effect on energy
expenditure persists. The compound also possesses repartitioning
properties, which may be useful in the treatment of obesity.
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Med Sci Sports
Exerc 2001 Aug;33(8):1399-403 |
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Effect
of caffeine and ephedrine ingestion on anaerobic exercise
performance.
Bell DG, Jacobs I, Ellerington K.
Defence and Civil Institute of Environmental Medicine, Toronto,
Ontario M3M 3B9, Canada.
doug.bell@dciem.dnd.ca
PURPOSE: Ingestion of a combination of caffeine (C) and ephedrine
(E) prolongs time to exhaustion during high-intensity aerobic
exercise. CNS stimulation by C and E was proposed as part of the
mechanism for the improvement. It was thought that this arousal
might also be of benefit during anaerobic exercise. The purpose of
this study was to investigate the effect of C, E, and C+E ingestion
on performance of anaerobic exercise. METHODS: Two groups were used
to evaluate the effect of C and E on anaerobic performance. Group 1
(WIN) consisted of 16 healthy untrained male subjects who performed
a 30-s Wingate test. Group 2 (MAOD) consisted of 8 healthy untrained
male subjects who performed a supramaximal (125%VO(2peak)) cycle
exercise trial to exhaustion to determine maximum accumulated oxygen
deficit. The trials commenced 1.5 h after ingesting either C (5 mg x
kg(-1)), E (1 mg x kg(-1)), a combination of C+E, or a placebo (P).
All trials were randomized and double blind. Blood samples were
assayed for lactate and glucose post drug ingestion just before
exercise, and again 3, 5, and 10 min post exercise. Catecholamines
were measured in the preexercise and 10-min postexercise blood
samples. RESULTS: Ephedrine increased power output during the early
phase of the Wingate test, whereas C increased time to exhaustion
and O(2) deficit during the MAOD test. C, E, and C+E increased blood
lactate, glucose, and catecholamine levels. CONCLUSION: The
improvement in anaerobic exercise performance is likely a result of
both stimulation of the CNS by E and skeletal muscle by C.
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Clin Pharmacol
Ther 2002 Jun;71(6):421-32 |
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Pharmacology of ephedra alkaloids and caffeine after single-dose
dietary supplement use.
Haller CA, Jacob P 3rd, Benowitz NL.
Division of Clinical Pharmacology, San Francisco General Hospital,
University of California, 94143, USA.
dchaller@worldnet.att.net
OBJECTIVE: Serious cardiovascular toxicity has been reported in
people taking dietary supplements that contain ma huang (Ephedra)
and guarana (caffeine). We assessed the pharmacokinetics and
pharmacodynamics of a dietary supplement that contains these herbal
stimulants. METHODS: Eight healthy adults received a single oral
dose of a thermogenic dietary supplement labeled to contain 20 mg
ephedrine alkaloids and 200 mg caffeine after an overnight fast.
Serial plasma and urine samples were analyzed by use of liquid
chromatography-tandem mass spectrometry for ephedrine alkaloid and
caffeine concentrations, and heart rate and blood pressure were
monitored for 14 hours. RESULTS: Plasma clearance and elimination
half-lives for ephedrine, pseudoephedrine, and caffeine were
comparable to published values reported for drug formulations. A
prolonged half-life of ephedrine and pseudoephedrine was observed in
1 subject with the highest urine pH. Mean systolic blood pressure
increased significantly to a maximum of 14 mm Hg above baseline at
90 minutes after ingestion (P <.001). There was a lag in the mean
heart rate response that reached a maximum change of 15 beats/min
above baseline at 6 hours after ingestion (P <.001). Diastolic blood
pressure changes were insignificant. Two subjects who were taking
oral contraceptives had longer caffeine half-lives (15.5 +/- 0.3
hours versus 5.6 +/- 1.7 hours) and lower values for oral clearance
(0.34 +/- 0.01 mL/min. kg versus 0.99 +/- 0.41 mL/min. kg) than
subjects who were not taking oral contraceptives. CONCLUSIONS:
Botanical stimulants have disposition characteristics similar to
their pharmaceutical counterparts, and they can produce significant
cardiovascular responses after a single dose.
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