A natural cosmetics ingredient relieves retinol’s side effects

As we know, retinol is outstanding for anti-aging, anti-wrinkle, but retinol’s side effects to the skin is unavoidable, due to its irritation on face. Especially when you are sensitive skin, after using cosmetics containing retinol, the skin may appear redness, tingling, peeling, and others. According to statistics, the rate of sensitive skin is around 50%, and the rate is increasing year by year because of UV, bad environment, stress, bad eating habits and lifestyle. Therefore, we can conclude that almost every cosmetics formulation need to add ingredients effectively but gently for soothing, and calming.

Plamed mainly focuses on natural cosmetics for sensitive skin. We develop PMSoothe^® Kava to relieve the irritation caused by retinol. We did the test by the third party lab to prove that.

• Relieve Retinol’s Side Effects Test

The test is based on hen’s egg test on the chorioallantoic membrane (HET-CAM). Due to the variety of chemical stimulation responses to CAM, the HET-CAM used hemorrhage, vessel lysis, and coagulation as the observation endpoint, that is, at the 9th day of embryo development, when nerve tissue and pain were not formed, to detect the severity of the three reactions caused by the subject. Generally, retiniol’s side effect to the skin will appear during the process of CAM test.

The sample retinol was diluted with olive oil to 10% concentration; the sample PMSoothe^® Kava + retinol was dissolved in oil and diluted to 1% PMSoothe^® Kava + 10% retinol. Negative control (0.9% sodium chloride solution) and positive control (1% sodium dodecyl sulfate) were also set up. All the sample groups are based on reaction time method for detection.

CAM preparation: 9-day-old chicken embryos were subjected to egg examination. The eggshell in the air chamber was peeled with dental zigzag bending forceps to expose the white egg membrane. Careful operation was performed without damaging the integrity of the egg membrane. Moisten the egg membrane with a drop of 0.9% sodium chloride (NaCl) solution, and carefully remove the inner membrane with tweezers to ensure that the vascular membrane is not damaged. Then observe the structure of the vascular system again, and determine its integrity and suitability for the test.

More information, please visit PMSoothe Kava Introduction

• Relieve Retinol’s Side Effects Test Method

Reaction time method: Apply 0.3mL of the subject to the CAM to ensure that at least 50% of the CAM surface is covered by the subject. The reaction of CAM was observed, and record the time when each toxic effect occurs within 5 minutes of action.

Result evaluation: irritation score (IS), a test conducted using the reaction time method, applies the below formula to calculate the irritation score (IS), and the result is retained after two decimal places:

Sec H (hemorrhage time)- the average time of hemorrhage observed on the CAM membrane, in seconds (s).

Sec L(vessel lysis time)- the average time (in seconds) when vessel lysis begins to occur observed on a CAM membrane. 

Sec C(coagulation time)- the mean time, in seconds (s), when coagulation begins to appear is observed on the CAM membrane.

Chart. Results evaluation of irritation score method

• Relieve Retinol’s Side Effects Test result

1. Sample retinol

2. Sample PMSoothe^®Kava + retinol

The results showed that at 10% concentration of retinol can cause moderate irritation; at concentration of 1% PMSoothe^® Kava + 10% retinol, it showed no irritation on CAM. In conclusion, PMSoothe^® Kava can relieve retinol’s side effects, including irritation to the skin.

Salicylic acid is another potent effect of softening cutin, anti-acne and antibacterial, but if salicylic acid is used in large doses for a long time, it may cause skin irritation and damage the skin barrier, resulting in sensitive skin. Therefore, we also did the same test using 1.25% salicylic acid and 1% PMSoothe^® Kava + 1.25% salicylic acid as samples, the results as below:

1. Sample salicylic acid (99% purity)

2. Sample PMSoothe^®Kava + salicylic acid

The results showed that at concentration of 1.25%, salicylic acid can cause moderate irritation; at concentration of 1% PMSoothe^® Kava + 1.25% salicylic acid, it showed no irritation on CAM. Therefore, PMSoothe^® Kava can soothe salicylic acid’s irritation in cosmetics formulation.

Besides retinol’s side effects, Phenylethyl Resorcinol also have side effects, it maybe cause allergic contact dermatitis when overdose. Although it is a widely used synthetic ingredient for skin whitening and anti-freckle. Thus Plamed test 10% Phenylethyl Resorcinol and 1% PMSoothe^® Kava+ 10% Phenylethyl Resorcinol on CAM. The results as below:

1. Sample Phenylethyl Resorcinol

2. Sample PMSoothe^®Kava + Phenylethyl Resorcinol

The results showed that at concentration of 10%, Phenylethyl Resorcinol can cause moderate irritation; at concentration of 1% PMSoothe^® Kava + 10% Phenylethyl Resorcinol, it showed no irritation on CAM. Therefore, PMSoothe^® Kava can relieve the irritation caused by Phenylethyl Resorcinol.

Figure. PMSoothe^® Kava soothes retinol’s side effect result on CAM

Choosing a soothing ingredients to improve retinol’s side effect is important for cosmetics formulation. Plamed PMSoothe® Kava can provide you an effective solution to solve this. PMSoothe® Kava not only can soothe retinol’s irritation, also relieve other irritating ingredients, including salicylic acid, Phenylethyl Resorcinol. In skincare products, PMSoothe® Kava can inhibit the overreaction of sensory nerves, thus significantly improving the skin’s tolerance to external stimuli, including some irritating ingredients. Also we recommend to add 0.5%~1.4% PMSoothe® Kava, according to the intensity of irritants.

Related Reading

1. PMSoothe® Kava introduction