What Is Ammonium Bicarbonate?
Ammonium bicarbonate, also called ammonium hydrogencarbonate, is a white crystalline powder made from ammonia, carbon dioxide and water. Chemically, it is a salt that releases small amounts of carbon dioxide when it meets acids or heat. This mild fizzing action once made it popular in old-fashioned baking powder. Today, that same steady release of gas makes it useful in cosmetics.
Centuries ago apothecaries produced ammonium bicarbonate by heating deer horn shavings, which is why you may see it called “salt of hartshorn” in historical texts. Modern production is simpler and greener: manufacturers combine liquid ammonia with carbon dioxide under controlled pressure, then cool and dry the mixture to form the powder.
In beauty products ammonium bicarbonate shows up mainly where a steady, gentle control of pH is needed. You will most often find it in rinse-off masks, clay masks, peel-off treatments, bath bombs, some hair tonics, certain facial cleansers and the occasional effervescent foot soak. Its presence keeps formulas stable and comfortable on the skin.
Ammonium Bicarbonate’s Cosmetic Benefits/Uses
The main reason formulators choose ammonium bicarbonate is its reliable buffering ability.
As a buffering agent it helps a product stay at the right pH all through its shelf life and while it sits on your skin. A balanced pH means the formula feels gentler, the active ingredients work as intended and preservatives stay effective. For the user this translates to better texture, less irritation and consistent results each time the product is applied.
Who Can Use Ammonium Bicarbonate
Because ammonium bicarbonate mainly acts as a pH buffer and rinses away easily, it suits most skin types including normal, oily, combination and even sensitive skin. People with very dry or compromised skin should still watch how their skin feels, since any salt can be mildly drying if left on too long.
Modern ammonium bicarbonate is synthesized from ammonia, carbon dioxide and water, so it contains no animal matter and is considered suitable for both vegans and vegetarians.
Current cosmetic safety data show no specific risks for pregnant or breastfeeding women when ammonium bicarbonate is used in rinse-off or short-contact products. This is not medical advice and anyone who is expecting or nursing should run the product past a healthcare provider to be sure it fits their personal circumstances.
The ingredient does not make skin more sensitive to sunlight, so it has no known effect on photosensitivity. It is also odorless, which makes it a good choice for people who avoid fragranced formulas.
Potential Side Effects/Adverse Reactions
Reactions to topical ammonium bicarbonate differ from person to person. The following points list potential side effects, but most users will not experience them when the ingredient is used correctly in a well-formulated product.
- Temporary tingling or mild stinging especially on freshly exfoliated or broken skin
- Short-lived redness in sensitive skin after application
- Dryness or tightness if the product is left on for longer than directed
- Rare allergic contact dermatitis presenting as itching, swelling or rash
- Eye irritation if the powder or product accidentally gets into the eyes
- Worsening of pre-existing skin conditions such as eczema when used in very high concentrations
If you notice any discomfort or persistent irritation stop using the product and seek advice from a healthcare professional.
Comedogenic Rating
Rating: 0 / 5
Ammonium bicarbonate is a water-soluble salt that does not leave any oily or waxy residue on the skin so it has no tendency to block pores. Because it is usually used in rinse-off masks, cleansers or short-contact treatments its contact time with the skin is brief, further lowering any clogging risk. For these reasons it earns a solid zero on the comedogenic scale.
This makes the ingredient suitable for people prone to acne or frequent breakouts. If irritation does occur it is more likely linked to individual sensitivity than to pore blockage.
One extra note: while non-comedogenic, its alkaline nature can feel drying if left on too long, which might prompt some skin types to overproduce oil later. Following the product directions avoids that issue.
Summary
Ammonium bicarbonate is mainly valued as a buffering agent that steadies a product’s pH, helping actives stay effective, textures remain pleasant and preservatives function properly. It performs this role by releasing tiny amounts of carbon dioxide that nudge the formula toward a mild, skin-friendly acidity whenever the pH starts to drift.
The ingredient is more of an unsung workhorse than a trendy headline grabber. You will not see it splashed across marketing campaigns, yet formulators appreciate its reliability in niche items like clay masks, bath fizzies and certain cleansers.
Safety data rate ammonium bicarbonate as low risk when used at cosmetic levels, especially in rinse-off products. Serious side effects are uncommon though any new skincare step can trigger an unexpected reaction, so it is wise to patch test a product containing this ingredient before applying it to a larger area.