Penicillin skin test solution is prepared by mixing 800,000 U of penicillin with 0.9% sodium chloride and finally taking 0.1 ml or 50 U of penicillin skin test. The 800,000 U of penicillin is matched with 4 ml of 0.9% sodium chloride, at which point 1 ml of liquid contains 200,000 U of penicillin. Another 0.1 ml of liquid was taken and mixed with 0.9 ml of 0.9% sodium chloride, and 20,000 U of penicillin was present in the liquid obtained. Take another 0.1 ml of the prepared liquid and match it with 0.9 ml of 0.9% sodium chloride, at this time the liquid contains 2,000 U of penicillin, take 0.25 ml of the liquid and match it with 0.75 ml of 0.9% sodium chloride, at this time the liquid contains 500 U of penicillin, and take 0.1 ml of it, i.e., 50 U of penicillin liquid, for the skin test. During the skin test, you should always observe the changes in the person being skin tested. Please have it done by a specialized physician.