Cleo 35 is a combination oral contraceptive tablet containing 2 mg of Cyproterone Acetate and 35 mcg of Ethinylestradiol. Cyproterone Acetate is a synthetic progestogen with antiandrogenic properties, while Ethinylestradiol is a synthetic estrogen. Together, they work to regulate hormonal activity, making Cleo 35 effective in treating conditions such as severe acne, hirsutism (excessive hair growth), and as a contraceptive method. The medication is typically taken in 28-day cycles, with 21 active tablets followed by 7 inactive tablets, and is usually started on the first day of the menstrual cycle.