Betaxolol is a selective beta₁ receptor blocker used in the treatment of hypertension and glaucoma. Being selective for beta₁ receptors, it typically has fewer systemic side effects than non-selective beta-blockers, for example, not causing bronchospasm (mediated by beta₂ receptors) as timolol may. Betaxolol also shows greater affinity for beta₁ receptors than metoprolol. In addition to its effect on the heart, betaxolol reduces the pressure within the eye (intraocular pressure). This effect is thought to be caused by reducing the production of the liquid (which is called the aqueous humor) within the eye. The precise mechanism of this effect is not known. The reduction in intraocular pressure reduces the risk of damage to the optic nerve and loss of vision in patients with elevated intraocular pressure due to glaucoma.