Betalucil extended-release tablets, also known as metoprolol succinate extended-release tablets, are generally effective for 24 hours. Metoprolol succinate extended-release tablets are a selective beta-blocker that is primarily used to treat various types of high blood pressure and angina pectoris. This medication comes in a multi-unit, small pill form, and each pellet will be individually wrapped in a film so that the rate of release of the medication can be controlled. Upper abdominal discomfort, fatigue, or sleep abnormalities may occur after taking this medication and may disappear with prolonged use. In addition, it should be used with caution in pregnant and breastfeeding women, those with hepatic insufficiency, and should not be used by those with II or III degree AV block, or those with severe bradycardia. This drug is a prescription drug, should be taken under the guidance of a doctor, do not apply without authorization.