Ammonium lactate is the ammonium salt of lactic acid. It is a medication that is used to treat scaly and dry skin conditions by increasing the moisture content in the skin. Lactic acid is a part of blood and tissues and so it decreases the corneocyte cohesion. Ammonium lactate cream is used to treat vulgaris, xerosis and ichthyosis. The side effects include burning, reddening or stinging on the skin. If the condition persists then it is better to consult a doctor.