Betaxolol is a selective
beta1 receptor blocker used in the treatment of
hypertension and
angina.[1] It is also a
adrenergic blocker with no partial agonist action and minimal membrane stabilizing activity.[2] 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.
It was patented in 1975 and approved for medical use in 1983.[3]
Medical uses
Hypertension
Betaxolol is most commonly ingested orally alone or with other medications for the management of
essential hypertension.[4] It is a cardioselective beta blocker, targeting beta-1 adrenergic receptors found in the cardiac muscle. Blood pressure is decreased by the mechanism of blood vessels relaxing and improving the flow of blood.[5][6]
Glaucoma
Ophthalmic betaxolol is an available treatment for
primary open angle glaucoma (POAG) and optical hypertension. Betaxolol effectively prevents the increase of intracellular calcium, which leads to increased production of the aqueous humor. In the context of open angle glaucoma, increased aqueous humor produced by ciliary bodies increases intraocular pressure, causing degeneration of
retinal ganglion cells and the optic nerve.[7]
Furthermore, betaxolol is additionally able to protect retinal neurones following topical application from
excitotoxicity or
ischemia-reperfusion, providing a neuroprotective effect. This is thought to be attributed to its capacity to attenuate neuronal calcium and sodium influx.[8] Betaxolol is also an effective treatment for
Intraocular pressure[9]
Paronychia
One study showed that topical betaxolol can be used in treating relapsed
paronychia.[10]
Contraindications
Hypersensitivity to the drug
Patients with
sinus bradycardia, heart block greater than first degree, cardiogenic shock, and overt cardiac failure
Side effects
This section needs expansion. You can help by
adding to it. (January 2019)
The adverse side-effects of betaxolol can be categorized into local and systemic effects.[7] The local effects include:
Betaxolol was approved by the U.S.
Food and Drug Administration (FDA) for ocular use as a 0.5% solution (Betoptic) in 1985 and as a 0.25% solution (Betoptic S) in 1989.
Society and culture
Brand names
Brand names include Betoptic, Betoptic S, Lokren, Kerlone.
^Buckley MM, Goa KL, Clissold SP (July 1990). "Ocular betaxolol. A review of its pharmacological properties, and therapeutic efficacy in glaucoma and ocular hypertension". Drugs. 40 (1): 75–90.
doi:
10.2165/00003495-199040010-00005.
PMID2202584.
S2CID46962082.
^
abTajran J, Goyal A (2022).
"Betaxolol". StatPearls. Treasure Island (FL): StatPearls Publishing.
PMID32491793. Retrieved 2023-01-12.
^Wood JP, Schmidt KG, Melena J, Chidlow G, Allmeier H, Osborne NN (April 2003). "The beta-adrenoceptor antagonists metipranolol and timolol are retinal neuroprotectants: comparison with betaxolol". Experimental Eye Research. 76 (4): 505–516.
doi:
10.1016/s0014-4835(02)00335-4.
PMID12634114.
^Goldberg I, Goldberg H (February 1995). "Betaxolol eye drops. A clinical trial of safety and efficacy". Australian and New Zealand Journal of Ophthalmology. 23 (1): 17–24.
doi:
10.1111/j.1442-9071.1995.tb01640.x.
PMID7619450.
^Yen CF, Hsu CK, Lu CW (June 2018). "Topical betaxolol for treating relapsing paronychia with pyogenic granuloma-like lesions induced by epidermal growth factor receptor inhibitors". Journal of the American Academy of Dermatology. 78 (6): e143–e144.
doi:
10.1016/j.jaad.2018.01.015.
PMID29339238.
S2CID39861588.
^Buckley MM, Goa KL, Clissold SP (July 1990). "Ocular betaxolol. A review of its pharmacological properties, and therapeutic efficacy in glaucoma and ocular hypertension". Drugs. 40 (1): 75–90.
doi:
10.2165/00003495-199040010-00005.
PMID2202584.
S2CID46962082.