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penbutolol

n. A beta blocker used in the treatment of high blood pressure.

Wikipedia
Penbutolol

Penbutolol (Levatol, Levatolol, Lobeta, Paginol, Hostabloc, Betapressin) is a medication in the class of beta blockers, used in the treatment of high blood pressure. Penbutolol is able to bind to both beta-1 adrenergic receptors and beta-2 adrenergic receptors (the two subtypes), thus making it a non-selective β blocker. Penbutolol is a sympathomimetic drug with properties allowing it to act as a partial agonist at β adrenergic receptors.

It was approved by the FDA in 1987 and was withdrawn from the US market by January 2015.