Dosages, treatment schedule and duration of treatment may be adapted to the severity of the dysfunction and the clinical response. Dysfunctional uterine bleeding: When treatment is started to arrest a bleeding episode Duphaston 10 mg b.d.(twice a day) for five to seven days. For continuous treatment Duphaston 10 mg b.d. from day 11 to day 25 of the cycle. Withdrawal bleeding occurs if the endometrium has been adequately primed with either endogenous or exogenous estrogen. Secondary amenorrhoea: Duphaston 10 mg b.d. from day 11 to 25 to produce an optimum secretory transformation of an endometrium that has been adequately primed with either endogenous or exogenous estrogen. Pre-menstrual syndrome: Duphaston 10 mg b.d. from day 12 to 26 of the cycle. The dosage may be increased if necessary. Endometriosis: Duphaston 10 mg two to three times daily from day 5 to 25 of the cycle, or continuously. Dysmenorrhoea: Duphaston 10 mg b.d. from day 5 to 25 of the cycle. Irregular cycles: Duphaston 10 mg b.d. from day 11 to 25 of the cycle. Infertility due to luteal insufficiency: Duphaston 10 mg b.d. from day 11 to 25 of the cycle.Treatment should be maintained for at least three consecutive cycles. Hormone replacement therapy: The standard dose is 10 mg Duphaston daily for the last 14 days of each 28-day estrogen treatment cycle. The dose may be increased to 10 mg twice daily if either early withdrawal bleeding occurs, or if endometrial biopsy reveals inadequate progestational response. In women who are not taking hormone replacement therapy, have established amenorrhoea or women who switch from a continuous combined hormone replacement therapy, treatment may be started on any convenient day. In women transferring from a cyclic or continuous sequential HRT regimen, treatment should begin the day following completion of the prior regimen. If the patient is menstruating, treatment is started within five days of the start of bleeding. For initiation and continuation of treatment of postmenopausal symptoms, the lowest effective dose for the shortest duration (see also section 4.4) should be used. Forgotten dose: If a dose has been forgotten, it should be taken as soon as possible. When more than 12 hours have elapsed, it is recommended to continue with the next dose without taking the forgotten tablet. The likelihood of breakthrough bleeding or spotting may be increased. There is no relevant use of dydrogesterone before menarche. The safety and efficacy of dydrogesterone in adolescents aged 12-18 years has not been established. Currently available data are described in section 4.8 and 5.1, but no recommendation on a posology can be made. Method of administration For oral use. For administration of higher dosages the tablets should be taken evenly distributed over the day.