What Is Ammonium Lactate Lotion?

Ammonium lactate lotion is a prescription lotion designed to heal excessively dry, chapped, irritated skin, or scaly skin. It also provides temporary relief of the itching associated with these conditions. Composed of an alpha-hydroxy acid, it is effective at hydrating the outlayer of the skin. Although relatively safe, treated areas should not be exposed to ultraviolet light.

Chemistry

Ammonium lactate contains 12 percent lactic acid neutralized with ammonium hydroxide. This produces a slightly acidic lotion of ammonium lactate, an ammonium salt of the alpha-hydroxy acid known as lactic acid, or 2-hydroxypropanoic acid. Lactic acid has the chemical formula COOHCHOHCH3.

In addition, the commonly prescribed 12 percent ammonium lactate formulation also contains mineral oil, glyceryl stearate, PEG-100 stearate, propylene glycol, polyoxyl 40 stearate, glycerin, magnesium aluminum silicate, laureth-4, cetyl alcohol, methyl and propyl parabens, methylcellulose, fragrance and water.

Pharmacology

Amonnium lactate acts to moisturize skin. The outermost layer of the epidermis of the skin is known as the stratum corneum. The amount of water contained in this layer determines whether skin is sufficiently moisturized. When the stratum corneum contains 10 percent or more water, the skin is moisturized, soft and pliable; below 10 percent, the skin is rough, dry, cracked and can become scaly and irritated, says the National Institutes of Health.

Ammonium lactate provides relief to irritated and dry skin by increasing the moisture content of the stratum corneum layer of the skin. Lactic acid, and the ammonium salt of lactic acid, work as hygroscopic compounds, absorbing and distributing relatively large volumes of water.

In addition to providing symptomatic relief of dry skin, prescription labeling of the ammonium lactate indicates that lactic acid and ammonium lactate reduce excessive epidermal keratinization, the thick skin found in patients with conditions such as icthyiosis, usually a genetic disease characterized by dry, thickened, scaly or flaky skin. Furthermore, a 1989 study conducted at the Dermatology Branch of the National Cancer Institute showed that ammonium lactate was also able to treat large inflammatory cysts and abscesses.

Side Effects

The most frequent side effect of using topical 12 percent ammonium lactate lotion is a stinging or burning sensation at the site of use, occuring in about 3 percent of all patients, but in about 10 percent of all patients with icthyosis. Erythema or rash and peeling occurs in about 2 percent of patients. Much less frequently occurring side effects include irritation, dryness, eczema, hyperpigmentation or increased coloring of the skin, or petechiae, small red or purple spots caused by broken capillary blood vessels.

Toxicity

Laboratory studies in rats reported by the National Library of Medicine and National Institutes of Health indicates that the topical treatment of mice with up to 30 percent ammonium lactate formulations for two-years was not toxic. It did not increase tumor formation. However, topically applied 12 percent ammonium lactate in mice did enhance the rate of tumor formation when exposed to ultraviolet light. Therefore, when using ammonium lactate formulations, patients should avoid using on skin areas that can be exposed to ultraviolet light.

Use in Pregnant or Lactating Women

While laboratory experiments in animals did not indicate any negative effects on fetuses or impaired fertility, there is not enough evidence to indicate the same is true for humans. Therefore, 12 percent ammonium lactate should only be used on pregnant or lactating women if clearly necessary according to research reported at drugs.com.