What are the daily maximum dosages for lopressor and toprol (metoprolol) xl?

Beta blockers: Lopressor is metoprolol tartrate, which is the short acting version and should be taken every 6 or 8 hours. Toprol xl is metoprolol succinate, which is the long acting version and can be taken once daily or divided into 2 doses per day. In each case, the maximum daily dose is approximately 400mg per day. In most cases, the dose is gradually increased until the desired treatment effect is reached.

Up to 450 mg/day: The usual initial dosage of Lopressor (metoprolol tartrate) tablets is 25-100 mg daily in single or divided doses. In general, the maximum effect of any given dosage level will be apparent after 1 week of therapy. The effective dosage range of Lopressor (metoprolol tartrate) tablets is 100-450 mg per day. Dosages above 450 mg per day have not been studied.