Red powder
1、 Red powder pharmacopoeia standard           This product is red mercury oxide (HGO).
        [character]   This product is orange red flake or powdery crystal. One side of the flake is smooth and slightly shiny, and the other side is rough. Powder orange. Hard and brittle; The color gradually darkens when exposed to light. Qiwei.
        [identification]   Take 0.5g of this product, add 10ml of water, mix well, slowly add an appropriate amount of hydrochloric acid to dissolve, and the solution shows the identification reaction of mercury salt (general rule 0301).
        [check]   Take 0.5g of mercurous compound and add 25ml of dilute hydrochloric acid. After dissolution, the solution is allowed to be slightly turbid.
        . If it is muddy, it shall not be thicker (0.006%) than the control solution made of 3ml of standard sodium chloride solution.
        [content determination]   Take about 0.2g of this product, weigh accurately, add 25ml of dilute nitric acid to dissolve, add 80ml of water and 2ml of ammonium ferric sulfate indicator solution, and titrate with ammonium thiocyanate titrant (0.1mol/l). Each 1ml ammonium thiocyanate titrant (0.1mol/l) is equivalent to 10.83mg of mercury oxide (HGO).
        The content of mercury oxide (HGO) in this product shall not be less than 99.0%.
        [nature, taste and meridian tropism]   ; It is highly toxic. Return to the lung and spleen meridians.
        ; Detoxify, remove pus, remove decay, and regenerate muscle. It is used for carbuncle, rash, syphilis, chancre, all kinds of sores, dark purple and black meat, rotting meat, sinus fistula, pus dripping, and long-term failure to close.
        [usage and dosage]   For external use, grind very fine powder for single use or combine with other medicinal flavors to form powder or medicine twist.
        [note]   This product is toxic and can only be used externally, not orally; It is also not suitable for long-term use; Forbidden for pregnant women.
        ; Place in a dry place, shaded and sealed.


2、 Chemical composition of red powder
It mainly contains mercury oxide (HGO) and mercury nitrate [hg (NO3) 2].

3、 Pharmacological action of red powder
. However, due to the different compatibility and refining methods of red powder, there are also differences in drug composition, bactericidal power and curative effect.
2. promote wound healing: for postoperative wound infection, wipe the wound with normal saline cotton ball, sprinkle a thin layer of red powder, and cover it with sterile dressing. When the pus is reduced and the granulation is regenerated, use normal saline gauze. Compared with the surgical incision infection cases using rivanol gauze alone, the wound healed in advance, and the curative effect was significantly different.
3. in vivo process: after cutting off the 2cm × 2cm wound of the full-thickness skin of rats and spreading the red powder dry powder on it for 4 hours, the mercury content of blood, brain, liver, kidney and other tissues increased significantly, and the mercury content of visceral tissues increased with the increase of the dose, with kidney containing the most mercury, followed by liver, blood and brain. There was a significant difference from the control group.
4. toxicity: the median lethal dose of Hongfen suspension by gavage in mice is 120.98 ± 1.71mg/kg, which is a moderately toxic drug. It was also reported that the median lethal dose of mercuric oxide administered by gavage was 22mg/kg in mice and 18mg / kg in rats. The lethal dose of crude mercury oxide to human is 1-1.5g, and that of mercury oxide is 0.1-0.7g.