(7.1) • CYP2D6 Inhibitors are likely to increase metoprolol concentration. (7.2) • Beta-blockers including metoprolol, may exacerbate the rebound hypertension that can follow the withdrawal of clonidine. Observe patients treated with metoprolol succinate extended-release plus a catecholamine depletor for evidence of hypotension or marked bradycardia, which may produce vertigo, syncope, or postural hypotension.
Source: FDA drug label - metoprolol succinate