One of the known side effects of Betaone (metoprolol) is loss of libido and erectile dysfunction in males. However, there is another aspect that needs to be considered. Metoprolol is known to precipitate diabetes. It is because of this reason that the internationally reputed British National Institute of Clinical Excellence (NICE) has placed propranolol (and other similar 'olols' such as atenolol, propranolol, etc.) at the bottom of anti-hypertensive therapy, i.e. to be used only when other treatments are not effective. In the case of sexually active young males under the age of 55 years, the first option is enalapril (sold as Enam) 5-10 mg 1-2 times daily as per response.