Metropolol half life is 3-7 hours. how can metropolol succinate stay in the bloodstream for 24 hours if half life is only 3-7 hours?

Different forms: Half-life elimination and duration of action are two different things. Metoprolol given IV has a different duration of action from oral metoprolol tartrate or metoprolol succinate. Metoprolol succinate (Toprol-XL) is the extended release formulation with a duration of action ~24hrs. ..

They are different: Metoprolol does have a 3-7 half-life, but that’s metoprolol tartrate, which is immediately absorbed into the bloodstream. The succinate version of metoprolol, however, also comes in a tablet (“extended-release”) that gives a person small amounts of medication over 24 hours. So the half-life - the rate the person eliminates the drug - is not different, but the rate the tablet releases it is.