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How to Create a Stable Urea Formula (8/25 Exclusive)

Is naturally found in our skin. It is one of the many Natural Moisturizing Factors (NMF) located in the stratum corneum (SC). Other NMFs are amino acids, hyaluronic acid, sodium PCA, lactic acid, ceramides, fatty acids, phospholipids, glycerin, saccharides, pyrrolidone, carboxylic acid, and triglycerides. 


Why use Urea?

Urea is commonly used in products to help repair dry flakey skin. At lower concentrations it can help moisturize and hydrate the skin. At higher concentrations if can actually act as an exfoliant. You may find Urea in lotions formulated to treat dryer areas of the body like elbow, knees, and feet. This is why you will commonly see this ingredient in a foot cream. 


Urea Usage Rate

  • Depending on the amount of urea used you will see different results

  • 1- 3% - For sensitive skin. Acts as a humectant & emollient. 

  • 4-5% - Should still be non exfoliating for most people. 

  • 10% or more - Exfoliates, hydrates, & moisturizes


Important Formulating Info

  • Urea is extremely unstable

  • It’s most stable between at pH of 4-8. (7.5 and above may produce odor)

  • Temperatures of 95°F / 35°C causes the pH of Urea to increase over time. In only 3 months the pH can increase to 11 and produce an odor. 

  • Use 1.5% Gluconolactone for ever 10% Urea to help keep the pH stable.

  • Using Triacetin can help reduce odor (1part Triacetin : 10 part Urea)


My Experience w/ Urea

There is no way around NOT using Gluconolactone as a stabilizer. I tried using lactic acid and it did work out. The pH increase too much at 35°C / 95°F for 3 months. This method wouldn’t work if you want to sell a product with Urea. If you are making it for yourself and want to try this, make sure you check the pH daily as it can increase overtime. Some other suggestions I have received from patrons:


“ for my formulation using urea I’m doing a combo of 3 groups to stabilize my emulsion. A chelating agent ( tetrasodium glutamate diacetate) , a buffer solution (sodium citrate, citric acid) and an acid (gluconolactone). There’s a possibility to use glycol triacetate to improve the stability the more.”


“Have you tried to buffer the urea with sodium lactate? Use 2% sodium lactate based on your urea.”


5% Urea Lotion Formula

Phase A


Phase B


Phase C


Phase D

Natural pH - 3.4

Adjusted pH - 4

pH at room temperature (70°F / 21°C) after 3 months - 4.3

pH at 95°F / 35°C after 3 months - 7.2


  • Formula is stable enough for home crafters to use on themselves, but I wouldn’t recommend selling this unless you do further testing. It is a good STARTING formula that you can adjust for selling purposes after doing proper testing.

  • Store in a cool dry area to prevent pH from raising. Check pH periodically if you have the product for a long time. (Use at own risk)


10% Urea Lotion Formula

Phase A


Phase B


Phase C


Phase D

Natural pH - 3.18

Adjusted pH - 4

pH at room temperature (70°F / 21°C) after 3 months - 4.5

pH at 95°F / 35°C after 3 months - 6.8


  • Formula is stable enough for home crafters to use on themselves, but I wouldn’t recommend selling this unless you do further testing. It is a good STARTING formula that you can adjust for selling purposes after doing proper testing.

  • Store in a cool dry area to prevent pH from raising. Check pH periodically if you have the product for a long time. (Use at own risk)


Directions to make lotions;

  1. Combine phase A in a heat safe beaker.

  2. Combine phase B in a heat safe beaker.

  3. Pour phase B into A and mix well.

  4. Tare scale and weight phase A/B. Take not of the weight. We will be heating it up and some of the water will evaporate and we will need to replace that water after heating.

  5. In another heat safe sanitized beaker, combine phase C.

  6. Create a water bath by filling a pan with about an inch of water and place over medium heat.

  7. Place both phase A/B and C in the water bath and heat until phase C is melted and phase A/B is around the same temperature.

  8. Once phase A/B is around the same temperature as phase C and phase C is melted, you can remove from heat.

  9. Before pouring phase A/B into phase C make sure you replace any water in phase A/B that evaporate.

  10. Then after you pour phase A/B into phase C, you can mix with an immersion blender.

  11. Let cool.

  12. In another sanitized beaker, combine all ingredients in phase D and mix until Gluconolactone has dissolved.

  13. Once lotion has cooled to around 104°F / 40°C you can add in the phase D ingredients & mix to combine.

pH adjusting - raise pH to 4 using either a 10% dilution of sodium hydroxide, Triethanolamine, or by using L-arginine. (I used 0.5% of a 10% dilution of sodium hydroxide to raise pH from 3.4 to 4.)


Plans for my next Urea lotion


Other Urea Info

  • White to off-white crystal/powder

  • Water soluble. (Meaning it will dissolve in water.)

  • 1 gram or urea will dissolve in; 1 ml of water, 10 ml of 95% alcohol, or 2 ml of glycerol. (I will be using water to dissolve it.)

  • Has moisturizing and hydrating benefits

  • Replenishes natural skin urea lost to cleansing

  • Exfoliates the skin

  • Can act as an anti-inflammatory on damaged skin

  • Add to water phase of formulations

  • Recommended usage rate; 2-5% or up to 40%

  • Can work as a keratolytic agent (reduce dead skin build up) when used at high amounts. (10-20%)

  • Can be used to treat nail fungus at 20% or higher

  • Has deodorizing effects, which make is great for foot products and deodorants.

  • Most stable in a pH between 4-8

  • pH of products using urea will increase in hot climates causing instability. (Might need paired with a low pH ingredient like an AHA or BHA to keep pH stable.)

  • Fun Fact, Urea can be found in the urine of mammals, but we make it synthetically for our cosmetics. So don’t worry, we aren’t using urine here.



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