What Is Carboxymethyl Chitosan Myristamide?
Carboxymethyl Chitosan Myristamide is a modified form of chitosan, the naturally occurring polymer obtained from the shells of shrimp, crab or other crustaceans. Chemists first convert chitosan into carboxymethyl chitosan to improve its water solubility, then react it with myristic acid, a fatty acid that also occurs in nutmeg butter and coconut oil. The result is a hybrid molecule that combines the moisture-loving backbone of chitosan with a skin-conditioning lipid tail.
Interest in this ingredient grew in the early 2000s when formulators looked for gentler alternatives to synthetic moisturizers. By attaching a natural fatty acid to chitosan, researchers created a humectant that not only attracts water but also has a silky skin feel. Production typically involves dissolving carboxymethyl chitosan in a controlled alkaline solution, adding activated myristic acid, then neutralizing and purifying the final material.
You will most often see Carboxymethyl Chitosan Myristamide in hydrating serums, sheet masks, lightweight lotions, gel creams, after-sun products and soothing overnight treatments where long-lasting moisture is a key selling point.
Carboxymethyl Chitosan Myristamide’s Cosmetic Benefits/Uses
Formulators reach for this ingredient because it excels at drawing water into the skin surface, leaving it plumper and smoother.
As a humectant, Carboxymethyl Chitosan Myristamide binds atmospheric moisture and holds it against the skin. This helps maintain a healthy hydration balance, softens rough patches and can enhance the spreadability of other actives within a formula, ultimately giving products a comfortable, non-sticky finish.
Who Can Use Carboxymethyl Chitosan Myristamide
This humectant is generally well tolerated by most skin types including dry, normal, combination and even oily complexions looking for light hydration without heaviness. Its water binding ability makes it particularly helpful for dehydrated or mature skin that needs extra moisture support. Sensitive skin users also tend to do well since the ingredient is non acidic and has a smooth, cushiony feel.
Because it is derived from chitosan obtained from crustacean shells, it is not considered vegan or vegetarian friendly. Anyone following strict plant based routines will want to choose alternatives sourced from plants or synthetic fermentation.
No specific data link Carboxymethyl Chitosan Myristamide to risks during pregnancy or breastfeeding. The molecule stays on the skin surface and is not known to penetrate deeply or act hormonally. That said this is not medical advice. Pregnant or nursing individuals should review any skincare products with their healthcare provider to be extra cautious.
The ingredient does not increase sun sensitivity, so it will not make skin more prone to burning. Standard daytime sun protection practices still apply, but there is no special photo caution beyond normal SPF use.
Potential Side Effects/Adverse Reactions
Reactions to topical Carboxymethyl Chitosan Myristamide vary from person to person. The effects listed below are possible yet uncommon when the ingredient is properly formulated and used as directed.
- Allergic response in individuals with shellfish allergy redness, swelling or hives may occur because the base material comes from crustaceans
- Mild irritation slight stinging or itching can appear on very reactive or compromised skin barriers
- Contact dermatitis rare inflammatory rash may develop from individual sensitivity to chitosan derivatives
- Eye discomfort watering or burning if the product accidentally migrates into the eyes
If any of these issues arise discontinue use immediately and consult a healthcare professional or dermatologist for assessment and guidance.
Comedogenic Rating
Rating: 1 / 5
Although the molecule carries a myristic acid tail, it is attached to a large water-soluble chitosan backbone that stays mainly on the skin surface. This bulky structure limits its ability to slip into pores and solidify, so the ingredient has a very low tendency to clog. The tiny amount typically used in formulas, usually below 2 percent, further reduces any pore-blocking risk.
Suitable for acne-prone or breakout-prone skin in most cases.
Because the base material comes from shellfish, anyone testing for potential breakouts should also watch for allergy-related redness that can mimic acne.
Summary
Carboxymethyl Chitosan Myristamide works mainly as a humectant, pulling water from the air and binding it to the skin surface. The chitosan backbone attracts and holds moisture while the myristic tail adds a soft, conditioned feel, so formulas get long-lasting hydration without greasiness.
It remains a niche ingredient rather than a mainstream bestseller, yet formulators who want a natural-leaning hydrator with a silky glide keep it on their short list.
Overall safety data are favorable with only shellfish allergies and rare irritation to consider. As with any new skincare product a quick patch test on a small area is a smart precaution before full-face use.