RX only.

*Lac-Hydrin, specially formulates 12% lactic acid, neutralized with ammonium hydroxide, as ammonium lactate to provide a lotion pH of 4.5-5.5. Lac-Hydrin also contains light mineral oil, glyceryl stearate, PEG-100 stearate, propylene glycol, polyoxyl 40 stearate, glycerin, magnesium aluminum silicate, laureth-4, cetyl alcohol, methyl and propylparabens, methylcellulose, fragrance, and water. Lactic acid is a racemic mixture of 2-hydroxypropanoic acid and has the following structural formula:


It is generally accepted that the water content of the stratum corneum is a controlling factor in maintaining skin flexibility. When the stratum corneum contains more than 10% water it remains soft and pliable; however, when the water content drops below 10% the stratum corneum becomes less flexible and rough, and may exhibit scaling and cracking and the underlying skin may become irritated.

Symptomatic relief of dry skin is provided by skin protectants containing hygroscopic substances (humectants) which increase skin moisture. Lactic acid, an (alpha)-hydroxy acid, is reported to be one of the most effective naturally occurring humectants in the skin. The (alpha)-hydroxy acids (and their salts), in addition to having beneficial effects on dry skin, have also been shown to reduce excessive epidermal keratinization in patients with hyperkeratotic conditions (e.g., ichthyosis).

:   The mechanism of action of topically applied neutralized lactic acid is not yet known.

Lac-Hydrin is indicated for the treatment of dry, scaly skin (xerosis) and ichthyosis vulgaris and for temporary relief of itching associated with these conditions.


Known hypersensitivity to any of the label ingredients.


General:  For external use only. Avoid contact with eyes, lips or mucous membranes. Stinging or burning may occur when applied to skin with fissures, erosions or that is otherwise abraded (for example, after shaving the legs). Caution is advised when used on the face because of the potential for irritation. The potential for post-inflammatory hypo- or hyperpigmentation has not been studied.

Information for Patients:  Patients using Lac-Hydrin (ammonium lactate) Lotion should receive the following information and instructions:

  1. This medication is to be used as directed by the physician, and should not be used for any disorder other than for which it was prescribed. Caution is advised when used on the face because of the potential for irritation. It is for external use only. Avoid contact with eyes, lips, or mucous membranes.
  2. Patients should minimize or avoid use of this product on areas of the skin that may be exposed to natural or artificial sunlight, including the face. If sun exposure is unavoidable, clothing should be worn to protect the skin.
  3. This medication may cause transient stinging or burning when applied to skin with fissures, erosions, or abrasions (for example, after shaving the legs).
  4. If the skin condition worsens with treatment, the medication should be promptly discontinued.

Carcinogenesis, Mutagenesis, Impairment of Fertility: A long-term photocarcinogenicity study in hairless albino mice suggested that topically applied 12% ammonium lactate cream enhanced the rate of ultraviolet light-induced skin tumor formation. Although the biological significance of these results to humans is not clear, patients should minimize or avoid use of this product on areas of the skin that may be exposed to natural or artificial sunlight, including the face. Long-term dermal carcinogenicity studies in animals have not been conducted to evaluate the carcinogenic potential of ammonium lactate.

Pregnancy (Category C):   Animal reproduction studies have not been conducted with Lac-Hydrin. It is also not known whether Lac-Hydrin can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Lac-Hydrin should be given to a pregnant woman only if clearly needed.

Nursing Mothers:   Although lactic acid is a normal constituent of blood and tissues, it is not known to what extent this drug affects normal lactic acid levels in human milk. Because many drugs are excreted in human milk, caution should be exercised when Lac-Hydrin is administered to a nursing woman.

Pediatric Use:   Safety and effectiveness of Lac-Hydrin have been demonstrated in infants and children. No unusual toxic effects were reported.


The most frequent adverse experiences in patients with xerosis are transient stinging (1 in 30 patients), burning (1 in 30 patients), erythema (1 in 50 patients) and peeling (1 in 60 patients). Other adverse reactions which occur less frequently are irritation, eczema, petechiae, dryness and hyperpigmentation.

Due to the more severe initial skin conditions associated with ichthyosis, there was a higher incidence of transient stinging, burning and erythema (each occurring in 1 in 10 patients).


The oral administration of Lac-Hydrin to rats and mice showed this drug to be practically non-toxic (LD 50 >15 mL/kg).


Shake well. Apply to the affected areas and rub in thoroughly. Use twice daily or as directed by a physician.


225g (NDC 0072-5712-08; NSN 6505-01-216-6274) plastic bottle and 400g (NDC 0072-5712-14) plastic bottle.

Store at controlled room temperature (15°-30°C; 59°-86°F).


  1. Blank IH: Further observation on factors which influence the water content of the stratum corneum. J Invest Dermatol 21:259-271, 1953.
  2. Blank IH: Factors which influence the water content of the stratum corneum. J Invest Dermatol 18:433-440, 1952.
  3. Middleton JD: Sodium lactate as a moisturizer. Cosmetics and Toiletries 93:85-86, 1978.
  4. VanScott EJ and Yu RJ: Modulations of keratinization with (alpha)-hydroxy acids and related compounds. In Recent Advances in Dermatopharmacology, P. Frost, E.E. Gomez and N. Zaias (eds) Spectrum Publications, Inc. NY, 211-217, 1977.


Princeton, NJ USA 08543                              Revised August 1999

A Bristol-Myers Squibb Company                       E7-B001B-08-99