Eumovate cream and ointment both contain the active ingredient clobetasone butyrate, which is a type of medicine called a topical corticosteroid.
Corticosteroids are medicines used for reducing inflammation. Inflammation of the skin happens as a result of allergy or irritation of the skin, and is caused by the release of various substances that are important in the immune system. These substances cause blood vessels to widen and result in the irritated area becoming red, swollen, itchy and painful, such as is seen in dermatitis or eczema.
When clobetasone is applied to the skin it works by acting inside the skin cells to decrease the release of these inflammatory substances. This reduces inflammation, redness and itch.
There is a range of potencies of corticosteroids that can be applied to the skin. Clobetasone butyrate is classed as a moderately potent corticosteroid. It is prescribed for the treatment of eczema and dermatitis, and may also be used as maintenance treatment between courses of more potent steroids. (Smaller tubes of clobetasone can also be bought from pharmacies for the short-term treatment of eczema and dermatitis flare-ups.