I have been finding more little companies selling this herb as an alternative to that nasty icky Ephedra (I had BAD reactions to a stacker product)

Anyone know more than the sales pitch?? or tried it??

At one of my regular supplement haunts online I found this about Citrus aurantium:

Supplement:
Synephrine

Description:
Synephrine is the main "active" compound found in the fruit of a plant called Citrus aurantium. The fruit is also known as zhi shi (in traditional Chinese medicine), and as green orange, sour orange and bitter orange in other parts of the world. Synephrine is chemically very similar to the ephedrine and pseudo-ephedrine found in many OTC cold/allergy medications and in a number of weight loss and energy supplements which contain Ma Huang.

Claims:
Increases metabolic rate
Increases caloric expenditure
Fat burner
Promotes weight loss
Increases energy levels


Theory:
Because synephrine is a stimulant, similar to caffeine and ephedrine, it is thought to have similar effects in terms of providing an energy boost, suppressing appetite and increasing metabolic rate and caloric expenditure. In traditional Chinese medicine (TCM), zhi shi is used to help stimulate the Qi (energy force). Although synephrine and several other compounds found in zhi shi are structurally similar to ephedrine and are known to act as stimulants (via adrenergic activity), zhi shi does not appear to have the same negative central nervous effects of ma huang (ephedra). Through its stimulation of specific adrenergic receptors (beta-3, but not beta-1, beta-2 or alpha-1), zhi shi is theorized to stimulate fat metabolism without the negative cardiovascular side effects experienced by some people with Ma Huang (which stimulates all beta-adrenergic receptors).

Scientific Support:
The effects of synephrine alone or in combination with other ingredients such as kola nut and guarana (both are caffeine sources) or with salicylates such as white willow (a natural form of aspirin) generally fall into the category of acting as a mild stimulant. The extract of citrus aurantium, in addition to synephrine, also contains tyramine and octopamine. Octopamine may be related in some way to appetite control, as it is thought to influence insect behavior by stopping bugs from eating the citrus fruit (so if you’re an insect, this may be the perfect weight loss supplement for you). Importantly, each of these related compounds (synephrine, ephedrine and octopamine) can result in elevated blood pressure

A recent study conducted in dogs suggests that synephrine and octopamine can increase metabolic rate in a specific type of fat tissue known as brown adipose tissue (BAT). This effect would be expected to increase fat loss in humans – except for one small details – adult humans don’t have brown adipose tissue.
As it stands now, citrus aurantium extract exists as one of the most over-hyped ingredients on the weight loss scene. There are some interesting theories on how it might work to increase metabolic rate and promote weight loss, but most are couched in pseudo-scientific mumbo jumbo and none are backed by any credible scientific evidence of effectiveness in humans.


Safety:
Both isolated synephrine and citrus aurantium extract have been shown to raise blood pressure in animal studies. Until more studies are conducted on the safety, pharmacology and efficacy of citrus aurantium as a thermogenic supplement, it should be treated as an ingredient with mild stimulant properties and should be avoided by individuals with cardiovascular concerns such as hypertension.

Value:
The most likely explanation for weight loss effects attributed to citrus aurantium supplements is the amphetamine-like effects of the alkaloids. Although this effect is likely to be somewhat less dramatic that effects induced by Ma Huang (ephedra alkaloids), users can expect variable effects including reduced appetite and heightened feelings of energy (similar to caffeine) – both of which are likely to result in weight loss.

Dosage:
Because synephrine is but one small component of the Citrus aurantium fruit, a standardized extract is recommended. A dose of 4-20 mg of synephrine per day is a typical dose found in products providing 200-600 mg of a standardized citrus aurantium extract (3-6% synephrine).

References
1. Candelore MR, Deng L, Tota L, Guan XM, Amend A, Liu Y, Newbold R, Cascieri MA, Weber AE. Potent and selective human beta(3)-adrenergic receptor antagonists. J Pharmacol Exp Ther. 1999 Aug;290(2):649-55.

2. Carpene C, Galitzky J, Fontana E, Atgie C, Lafontan M, Berlan M. Selective activation of beta3-adrenoceptors by octopamine: comparative studies in mammalian fat cells. Naunyn Schmiedebergs Arch Pharmacol. 1999 Apr;359(4):310-21.

3. Chen X, Liu LY, Deng HW, Fang YX, Ye YW. The effects of Citrus aurantium and its active ingredient N-methyltyramine on the cardiovascular receptors. Yao Hsueh Hsueh Pao. 1981 Apr;16(4):253-9.

4. Fontana E, Morin N, Prevot D, Carpene C. Effects of octopamine on lipolysis, glucose transport and amine oxidation in mammalian fat cells. Comp Biochem Physiol C Pharmacol Toxicol Endocrinol. 2000 Jan;125(1):33-44.

5. Galitzky J, Carpene C, Bousquet-Melou A, Berlan M, Lafontan M. Differential activation of beta 1-, beta 2- and beta 3-adrenoceptors by catecholamines in white and brown adipocytes. Fundam Clin Pharmacol. 1995;9(4):324-31.

6. Galitzky J, Carpene C, Lafontan M, Berlan M. Specific stimulation of adipose tissue adrenergic beta 3 receptors by octopamine. C R Acad Sci III. 1993;316(5):519-23.

7. Hu S, Wang G. Textual studies on shangzhou zhiqiao fructus Aurantii. Chung Kuo Chung Yao Tsa Chih. 1996 Mar;21(3):137-8, 189.

8. Langin D, Portillo MP, Saulnier-Blache JS, Lafontan M. Coexistence of three beta-adrenoceptor subtypes in white fat cells of various mammalian species. Eur J Pharmacol. 1991 Jul 9;199(3):291-301.

9. Miyazawa M, Okuno Y, Fukuyama M, Nakamura S, Kosaka H. Antimutagenic activity of polymethoxyflavonoids from Citrus aurantium. J Agric Food Chem. 1999 Dec;47(12):5239-44.

10. Satoh Y, Tashiro S, Satoh M, Fujimoto Y, Xu JY, Ikekawa T. Studies on the bioactive constituents of Aurantii Fructus Immaturus. Yakugaku Zasshi. 1996 Mar;116(3):244-50.

11. Zhang ZZ, Fan CS, Huang AH. A study on the quality of fruits of Citrus aurantium L. (zhishi and Zhiqiao) produced in Jiangxi. Chung Kuo Chung Yao Tsa Chih. 1989 Sep;14(9):520-2, 573.

12. Zhao NK. Cultivation of Citrus aurantium. Chung Yao Tung Pao. 1984 Mar;9(2):56-7.


I havent tried it myself (I take an ECA stack with no side effects); I'm sure Dan will have some input for you.

Nat

Wow.. thanks for the info.. I found a pre-made ECA stack that uses this as its "E"...

Synephrine does NOT work. There is no science that supports its effects in humans, and from personal experience I can say that it didn't work for me.

All of what Nat posted is on the mark.