Huang Qi (黄芪 astragalus) and Mi Zhi Huang Qi (蜜炙黄芪 honey-fried astragalus)
At Fat Turtle Herb Company, Huang Qi is one the most popular herbs. Because it's generally safe in dosages up to 30 grams, practitioners freely prescribe Huang Qi in many different formulas. Yu Ping Feng San (玉屏风散 Jade Windscreen Powder) and Bu Zhong Yi Qi Tang (补中益气汤 Tonify the Middle and Benefit the Qi Decoction) are two of the most popular base formulas that use Huang Qi.
According to an article in Hei Long Jiang Zhong Yi Yao (黑龙江中医药 Heilongjiang Chinese Medicine & Pharmacology), translated and abstracted by Bob Flaws and available for free at Blue Poppy's TCM Infoline, regular Huang Qi is used in Yu Ping Feng San to help secure the exterior, disinhibit water and disperse swelling. Mi Zhi Huang Qi is used in Bu Zhong Yi Qi Tang to "upbear yang & lift the fallen, secure the qi & restrain desertion."
Benksy, Clavey and Stoger's 3rd Edition Materia Medica says that honey-fried Huang Qi
induces the astragalus to travel internally, and to specifically tonify and raise the clear qi of the middle burner. It is also somewhat moistening and is therefore more appropriate when the pattern involves blood deficiency, or dryness of the Spleen.
Chen and Chen's Chinese Medical Herbology and Pharmacology says
unprocessed Huang Qi (fresh or dried) has qualities better suited to treat exterior disorders, as it tonifies wei (defensive) qi, stops perspiration, regulates circulation of water, reduces edema, and promotes generation of flesh. The honey-processed herb has an enhanced ability to treat imbalances of the interior, such as Spleen and Lung qi deficiencies and yang deficiency. It is also commonly used to treat chronic cases of fatigue, diarrhea, organ prolapse, and all cases of deficiency.
When writing prescriptions, make sure you're using the right type of Huang Qi for the condition. Fat Turtle Herb Company carries regular Huang Qi and Mi Zhi Huang Qi in both raw and granule powder format.