In the past two years, a popular combination of ointments has emerged:
Urea cream + Retinoid cream. This popular duo is widely used for skin whitening, underarm darkening, dark buttocks from sitting, joint hyperpigmentation, keratosis pilaris… Is the effect really that magical?
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Is it effective? Let’s start with the conclusion.
Yes, for some people, it may indeed have a noticeable effect on refining the skin and brightening the complexion, but it is absolutely not suitable for any keratosis pilaris, skin darkening, or roughness.
After stating the conclusion, let’s discuss the evidence:
01 Urea Cream Low concentration (2%-10%):
Medium concentration (10%-30%):
High concentration (30%-50%):
The urea cream on the market currently has a common concentration of 10%, indications include: keratosis,手足皲裂, dry skin syndrome, ichthyosis, etc..
Urea Cream, Retinoid Cream
What are their respective effects? How to use them?
Moisturizing, maintaining skin barrier function, especially suitable for elderly skin dryness.
Moisturizing + promoting keratin metabolism, keratin metabolism can also promote the increase of the permeability efficiency of subsequent topical drugs, so the combined use of urea cream with other ointments also has a certain basis.
Keratin peeling, keratin peeling can be understood as a stronger promotion of keratin metabolism, often used for abnormal keratinization, such as the treatment of hyperkeratosis of the soles of the feet, such as corns, calluses (commonly known as “old calluses”).
Foot Crack
It can be used alone as a hand cream during the daily use period (short-term is better), and it is also used to improve skin flaking, skin roughness, and can also be used for not too severe hand and foot eczema; in addition, it can also be used in combination with glucocorticoid ointments or antifungal ointments for hyperkeratotic hand and foot eczema or fungal infections.
02 Retinoid Cream Promotes epidermal cell renewal:
Regulates epidermal cell proliferation and differentiation:
Inhibits sebaceous gland secretion:
Anti-inflammatory effect:
Regulates melanin production:
Stimulates the growth and division of epidermal cells, accelerating the shedding of the stratum corneum.
By regulating the proliferation and differentiation of epidermal cells, it makes the epidermis orderly.
Reduces skin oil production.
It has the effect of inhibiting the chemotaxis of white blood cells, so it has a certain anti-inflammatory effect.
Retinoic acid can affect the production of melanin in melanocytes, and it has an inhibitory effect on the activity of three types of catalytic enzymes such as tyrosinase, dopamine oxidase, and dihydroxyindole oxidase, thereby reducing the formation of melanin and lightening skin pigmentation. However, retinoic acid has no effect on the activity of tyrosinase in normal melanocytes and the components of melanin.
The indications in the instructions of retinoid cream can be used forcommon acne, flat warts, mucosal leukoplakia, pityriasis rubra pilaris, keratosis pilaris, and psoriasis as an adjuvant treatment.
Common Acne ←Slide left and right to view→
Similarly, there are different concentrations of retinoid cream, and two common concentrations are: 0.025% and 0.1%.
● The higher concentration 0.1% retinoid cream can be used for pityriasis rubra pilaris, keratosis pilaris, and psoriasis to play an auxiliary role;
● And 0.025% is commonly used for the treatment of common acne (but now it is mostly replaced by adapalene gel) and for situations where 0.1% retinoid cream is not tolerated
In addition, some disease guidelines also recommend the use of retinoid cream, such as the chicken skin mentioned at the beginning (“keratosis pilaris”) and post-inflammatory hyperpigmentation.
Back to the popular combination of urea cream + retinoid cream mentioned at the beginning, from the principle, this CP can indeed achieve less rough skin, orderly skin structure, and even a slight whitening effect through moisturizing + promoting skin renewal metabolism, etc.
But why did we just mention that it is not suitable for any situation? Let’s take the two situations that are most often mentioned by the bloggers as having miraculous effects as examples:
.
(but this whitening is mainly through promoting epidermal metabolism and even epidermal peeling, and indeed exists in areas with post-inflammatory hyperpigmentation).
01 Chicken skin Keratosis pilaris (keratosis pilaris, KP) is a common follicular keratinization disease, characterized by keratinized follicular papules with varying degrees of perifollicular erythema. It is prone to occur on the extensor sides of the upper arms and thighs and cheeks.
These risks should not be ignored
Chicken skin ←Slide left and right to view→
Many people with chicken skin also have perifollicular inflammation, and in this case, if only this CP is used, the irritability of retinoic acid may instead aggravate inflammation, cause more severe itching, more obvious erythema, and possibly worsen the rash. Therefore, in the treatment of keratosis pilaris, dermatologists often diagnose the condition of the rash, and if the inflammation is severe, they will first use or combine the use of glucocorticoid ointments to improve inflammation.
02 Dark buttocks from sitting The essence of dark buttocks from sitting is post-inflammatory hyperpigmentation (postinflammatory hyperpigmentation, PIH), caused by long-term sitting that压迫s and rubs the skin of the buttocks, leading to melanin pigmentation and thickening of the stratum corneum. So, in a sense, dark buttocks from sitting is also our skin’s adaptation and protection against sitting behavior.
If you simply use the urea cream and retinoid cream CP, it may indeed fade the dark buttocks from sitting, but it will also thin the skin, making the buttocks more susceptible to pressure and friction damage. So, when dealing with dark buttocks from sitting, we need to consider more than just lightening the color; we also need to address why it’s dark.
The most core recommendation for handling is to change the living habits that involve using the buttocks:
● Get up and move around for 5-10 minutes every half an hour of sitting; ● Additionally, consider using seat cushions/pressure sores for long periods to alleviate the pressure on the skin of the buttocks.
Furthermore, for better results:
● You can indeed try using retinoid cream, hydroquinone, etc. or persistently use moisturizing creams containing glycolic acid, niacinamide, etc.; ● If you are strongly willing, you can also seek adjuvant therapy such as intense pulsed light/laser.
So when can we try this popular combination?
01 Preliminary assessment of whether it is suitable for you to use Such as dark buttocks from sitting, if the long-term pressure factor cannot be removed, even if it works, new dark marks, redness, and itching will reappear quickly, and obvious chicken skin is also recommended to seek medical attention first.
So it is more suitable to try on your own simple roughness of elbows and knees, especially during the application process, pay attention to reducing friction on elbows and knees.
Once a day for each, urea cream in the morning and retinoid cream in the evening.
When can you try it?
Images from the internet
02 Start with low concentration and build tolerance Retinoid cream has certain irritancy, pay attention to start with low concentration and gradually build tolerance, avoid occlusion (Do not use plastic wrap, facial mask paper, etc., to cover the skin surface), stop using immediately if adverse reactions occur.
In the past, when using retinoid cream for facial acne, we would repeatedly advise spot application, do not apply over a large area, otherwise, peeling is likely to occur.
It is recommended to start with 10% urea cream and 0.025% concentration retinoid cream low concentration, 2-3 weeks later, based on the situation, if there is no itching or burning sensation at all, consider increasing the concentration to 15% urea cream and 0.1% retinoid cream.
* Retinoid cream is photosensitive, do not use it during the day.
Finally, a splash of cold water, in fact, to improve roughness and darkening, in many cases, simply applying moisturizing cream and reducing friction with basic care can achieve results (but it does require long-term persistence).
For conditions involving skin diseases such as “chicken skin” or peeling of hands and feet, it is best to consult a dermatologist for an assessment before using medication.
References