Nature: bitter, acrid, slightly cold

Enters: Spleen, Stomach, Large Intestine

Actions: Strongly moves/regulates Qi; directs Qi downward; eliminates food retention (particularly in the large intestine), breaks up stagnation and accumulation; resolves phlegm; relieves distention; unblocks the bowels

• Accumulation and stagnation: epigastric or abdominal pain and distention or indigestion with focal distention or gas.
• Accumulation and stagnation, including due to food retention in the large intestine: distention in the abdomen, constipation or diarrhea with tenesmus.
• Phlegm obstruction with Qi stagnation: distention and fullness in the chest and epigastrium.
• Particularly useful for stagnation in the chest and upper back.
• Lifts prolapse of the stomach, uterus, or rectum. Used with Qi tonics for gastriectasis, gastroptosis, rectal prolapse, uterine prolaspe, etc.
• Raises blood pressure.
• Contains cirantin (inhibits activity of periovicular hyaluronidase) which may account for its reported contraceptive effect.
• Recent use in Western OTC weight loss products.
• The herb may have some use in treating cardiogenic shock.
Liu: For urinary stones, Zhi shi helps the urethra relax.
Hsu: Stimulates GI motor activities, increases digestion; contracts the uterus; purgative; raises blood pressure.
DY: With Bai zhu to supplement without producing stagnation and drain without damaging the correct Qi, to fortify the spleen, disperse food stagnation, and effectively eliminate accumulations and distention. For the following indications, except as otherwise indicated, the two herbs should be stir-fried:
– 1. Accumulation of food, distention and fullness of the abdomen and epigastrium, and difficult bowel movements due to spleen Qi deficiency and Qi stagnation. (Zhi Zhu Wan) When the patient’s main complaint is abdominal and epigastric distention due to Qi deficiency and spleen deficiency with or without dampness, the dosage for Bai zhu should be very high – as much as 100g per day. In this case Bai zhu is generally used alone.
– 2. Splenomegaly and hepatomegaly due to Qi deficiency and stagnation.
– 3. Ptosis of the organs (stomach, uterus, and anus) due to central Qi deficiency. For these indications, honey mix-fried Huang qi, stir-fried Chai hu, and honey mix-fried Sheng ma should be added.

K&R: (maturity not stated) Sedative (CNS), antispasmodic, expectorant, eupeptic, sympatholytic.
• Bitter-cooling; fire excess, wood excess.
• Fire: tachycardia, anguish, nervousness, anxiety, insomnia, epilepsy.
• Wood: aerophagia, dyspepsia, digestive spasms, tachycardia of emotional origin, anxiety, insomnia.
• Good for cooling liver fire stemming from heart fire.

Dose: 3-9g

Examine.com on synephrine:

A recommended dosage is 10-20mg, taken thrice a day.

Acute dosages of 50mg are also frequently used, although not thrice a day.

1. Sources and pharmacology

Synephrine is found from the Bitter orange plant, latin name Citrus aurantium. The plant contains a few active ingredients, namely para-synephrine(p-synephrine) and octopamine.^[1][2] Although meta-synephrine and ortho-synephrine could exist in fruits, they have not been observed in C.aurantium.^[3]

Typically, ‘synephrine’ in supplements refers to P-synephrine despite m-synephrine (also known as phenylephrine) having many of the same properties.^[4]

2. Effects on fat metabolism

2.1. Mechanisms

P-synephrine is a beta-agonist compound similar to Ephedrine^[5][6]. It can increase the metabolic rate via increasing lipolysis and basal metabolic rate.^[1] These effects are independent of diet for the most part, and can exert a passive increase in basal metabolic rate to produce weight loss over an extended period of time.

Synephrine also has alpha-adrenergic antagonist capabilities. Affecting both the A1 and A2 receptors, albeit with a different potency.^[7] In both the cases of alpha and beta agonism, the effects of both forms of synephrine are much less than that of noradrenaline.

2.2. Human studies

It has been implicated in increasing the thermic effect of food, but one study noted this effect only in women.^[8]

3. Potential Synergism

P-synephrine (50mg) was shown to be highly synergistic with both the Bioflavonoids naringin and hesperidin, but not both, in regards to increases in basal metabolic rate.^[9]

Like Ephedrine, P-synephrine also shows synergism with Caffeine and is more pronounced in naive caffeine users.^[10]

 4. Safety profile

P-synephrine does not seem to be a causative agent in increasing blood pressure^[11][12][8]

The Bitter Orange itself (the parent plant) has been linked to increased systolic and diastolic blood pressure.^[13] Additionally, a common patented blend of P-synephrine known as Advantra-Z (which contains active bioflavonoids such as naringen and Hesperidin) has been linked to an increase in blood pressure.^[11]

Overall, usage of P-synephrine appears to be quite safe and free of most adverse side effects.^[14]