This study will be done to compare the impact of Rose Essence and placebo in improving sexual dysfunction , caused by methadone and increase of happiness in men treated with methadone . The research is a double blind clinical trial. The study sample population is consist of all male drug addicts referring to the addiction treatment center of Farabi Hospital in Kermanshah, which 60 of them will be selected by convenience method, and will be categorized into control and experiment. The subjects of both groups will be matched in terms of age, and the erectile function and happiness questionnaires will be distributed among them. In the experimental group, the participants will receive a capsule of rose essence daily , while the control group will receive a placebo capsule daily. The questionnaire will be re-distributed among both groups at the first, 4 weeks later, and at the end of the study (8 weeks after the start of the study), and the happiness and sexual function will be measured . In addition, at the beginning and end of the study, the blood sample will be sent to the laboratory in order to determine the level of the hormones.. Inclusion criteria: patients under methadone treatment; at least elementary education;be married; age between 20-48 years; have not sexual problems before treatment with methadone; no history of any glands disease, such as elevated prolactin and thyroid disorder. Exclusion criteria: allergy to products made from rose essence; changes in sexual activity because of (wife pregnancy, remarried, divorce).