Probable Cause



Alcohol is not completely volatile.

Inject after the alcohol is completely volatile.

Injection Angle, speed, or push speed.

Inject quickly, push slowly, and pull out slowly.

Swell on the inject site

The injection angle is too tilted.

Adjust the injection angle to 45-90.


Inject into capillaries

After pulling the needle, the swab should be pressed.

Overflow of drug solution

Pull the needle too slowly or the drug solution is not absorbed.

Cotton swabs are pressed.

After the drug solution is completely pushed into then stays for 15 seconds before push the neddld out.

The needle is too shallow to enter the skin layer.

Adjust the injection angle.


Push the neddle to quickly or shaking during preparetion the drug solution

The drug solution should not be shaken violently and the powder should be dissolved naturally.

The liquid won't pull out.

The negative pressure in the bottle is too high.

Inject air into the vial before dispensing.

Leakage of the syringe

Change a new syringe.

Subcutaneous scleroma

Inject the same site for a long time

Change the injection site every time, the injection site should be at least 2cm apart form the other one.

Take the hot compress to alleviate or eliminated the subcutaneous scleroma.