Clobetasol works by lowering your body's inflammatory reaction. It also suppresses the immune system's functioning. This means that taking clobetasol after other medications that suppress the immune system may cause those medications to work less effectively. If you take clobetasol regularly, it is important to understand its side effects and risks. Clobetasol belongs to a class of drugs called corticosteroids. Like other steroids, such as cortisol and prednisone, clobetasol can have many negative effects on your health if used incorrectly or for too long. The most common side effect of clobetasol is skin thinning. Your skin will become thinner over time if you use this medication regularly. Skin thinning may lead to more cuts, bruises, and wounds on your body. There is some evidence that people who take clobetasol for long periods of time may be at increased risk for diabetes. Long-term use of high doses of clobetasol may also lead to osteoporosis (brittle bone disease). People who take clobetasol should not receive blood products because it could affect their ability to fight off infection.