Beta-blocker betaxolol

Rey E, Jammet P, d Athis P, de Lauture D, Christoforov B, Weber S, Olive G. Effect of cimetidine on the pharmacokinetics of the new beta-blocker betaxolol. Arzneimittelforschmg... 

Lee, C.R., Coste, A.C., and Allen, J. (2988) Determination of the beta-blocker betaxolol and labelled analogues by gas chromatography/mass spectrometry with selected ion monitoring of the alpha-cleavage fragment (m/z 72). Biomedical and Environmental Mass Spectrometry, 16, 387-392. 

Beta-blockers are medications that reduce the workload of the heart and lower blood pressure. They are commonly prescribed to relieve angina (a type of chest pain, pressure, or discomfort) or treat heart failure. They also are prescribed for people who have high blood pressure (hypertension). Several beta-blockers (metoprolol, propanolol, betaxolol, bisoprolol, and nadolol) have been detected in municipal sewage effluents up to the pg/L level (Temes 1998) and in groundwater samples (Sacher et al. 2001). 

Benzbromarone, 127 Benzodiazepines, 48 Betaxolol, 26 Beta-blockers, 19,25,41 Biclodil, 38 Bifonazole, 93... 

Geriatric Considerations - Summary Systemic absorption of ophthalmic drugs may occur and cause adverse effects in older adults. Since betaxolol is beta-selective, cardiovascular, respiratory and CNS adverse effects occur less frequently than with beta-nonselective topical opthalmics. These effects may still occur therefore close monitoring for systemic side effects is warranted. Betaxolol maybe less effective than the nonselective topical beta-blockers with an average lOP reduction of 18%-26%. Tachyphylaxis may occur after long-term therapy. 

Beta-blockers, including carvedilol (Coreg), atenolol (Tenormin), betaxolol (Kerlone), metopro-lol (Lopressor, Toprol XL), penbutolol (Levatol), and propranolol (Inderal). 

The ongoing BETACAR study is comparing the safety and efficacy of betaxolol compared to carvedilol in heart failure [113]. The two beta-blockers appear to have similar effects on left ventricular ejection fraction [New York Heart Association (NYHA) class], exercise capacity and quality of life over 6 months [114]. However, final results are not yet available. 

The utility of hair in the detection of chronic beta-blocker administration was examined by Kintz and Mangin in 8 hypertensive patients. Betaxolol (3 cases, 1.2-2.7 ng/mg), sotalol (2 cases, 4.4-5.3 ng/mg), atenolol (1 case, 0.9 ng/mg), and propanolol (2 cases, 1.6-2.4 ng/mg) were identified. Relative changes in observance of treatment was revealed by sectional hair analysis in a case of betaxolol treatment. 

ACEBUTOLOL, ATENOLOL, BETAXOLOL, BISOPROLOL, METOPROLOL, PROPANOLOL CICLOSPORIN t risk of hyperkalaemia Beta-blockers cause an efflux of potassium from cells, and side-effect has been observed during cidosporin therapy Monitor serum potassium levels during co-administration > For signs and symptoms of hyperkalaemia, see Clinical Features of Some Adverse Drug Interactions, Hyperkalaemia... 

The respiratory and cardiovascular adverse effects of topical therapy with timolol or betaxolol have been studied in a randomized, controlled trial in 40 elderly patients with glaucoma (83). Five of the 20 allocated to timolol discontinued treatment for respiratory reasons, compared with three of the 20 patients allocated to betaxolol There were no significant differences in mean values of spirometry, pulse, or blood pressure between the groups. This study confirms that beta-blockers administered as eye-drops can reach the systemic circulation and that serious adverse respiratory events can occur in elderly people, even if they are screened before treatment for cardiac and respiratory disease. These events can occur using either the selective betaxolol agent or the non-selective timolol. 

Bronchospasm, which can be life-threatening, can be precipitated by beta-blocker eye-drops. Even betai-selective antagonists, such as betaxolol, can cause a substantial reduction in forced expiratory volume. Wheezing and dyspnea have been reported among patients using betaxolol the symptoms resolved after withdrawal. A cross-sectional study has shown that ophthalmologists were more aware than chest physicians about the use of beta-blocker eye-drops by patients with obstructive airways disease patient awareness was also poor (38,107). 

A 70-year-old woman treated with topical timolol for glaucoma developed a papular eruption on the arms and back, consistent with prurigo. All tests were within the reference ranges. There was no improvement after 1 month of topical corticosteroids. The eruption cleared completely within 1 month of timolol withdrawal. Betaxolol eye-drops were introduced and the eruption recurred within 1 week. When beta-blocker therapy was replaced by synthetic cholinergic eye-drops (drug unspecified) the eruption cleared completely without any recurrence a year later. 

Although cutaneous adverse effects have been previously described after oral beta-blockers, including timolol, this observation further suggests a class effect of topical beta-blockers. This case also suggests a cross-reaction between timolol and betaxolol. 

Beta-blockers that are available as eye-drops include timolol, metipranolol, and levobunolol, which are non-selective betai- and beta2-adrenoceptor antagonists, and betaxolol, a relatively cardioselective betai-adrenoceptor antagonist. Although selective betai-blockers are less likely to precipitate bronchospasm, this and other systemic effects can nevertheless occur (SED-12,1200). 

Beta-adrenergic blockers Betaxolol Carteolol Levobunolol Metipranolol Timolol Decrease aqueous inflow Stinging, dry eyes, blurred vision, blepharitis... 

Betaxolol, timolol Beta blockers Block actions of NE at ciliary epithelium 4- aqueous humor formation... 

Beta-blockers Timolol, betaxolol Reduce aqueous humour production Treatment of glaucoma Eye-drop solution, suspension, gelforming solution... 

Beta-blockers Timolol, betaxolol, carteolol, levobunolol, metipranolol Decreased aqueous secretion from the ciliary epithelium Topical drops... 

Which client would the nurse question administering the beta-adrenergic blocker betaxolol (Betoptic), ophthalmic drops ... 

In 6 patients stabilised on warfarin, acebutolol 300 mg three times daily for 3 days had no effect on prothrombin time response. Similarly, in one patient taking warfarin, neither atenolol 100 mg daily nor metoprolol 100 mg twice daily for 3 weeks had any effect on prothrombin time. Similarly, in studies in healthy subjects the following beta blockers had no clinically relevant effects on the pharmacokinetics and/or anticoagulant response to warfarin atenolol 100 mg daily, betaxolol 20 mg daily, bisoprolol 10 mg daily, esmolol, or metoprolol 100 mg twice daily. In contrast, the minimum steady state plasma warfarin levels of 6 healthy subjects rose by 15% when they took propranolol 80 mg twice daily in one study." Similarly, in another study in 6 healthy subjects given propranolol 80 mg twice daily for 7 days with a single dose of warfarin on day 4, the AUC of warfarin was increased by 16.3% and the in maximum serum level was increased by 23%, but there was no change in the prothrombin time. A patient stabilised on warfarin had a rise in his Brit-... 

One experimental study indicated that no interaetion occurred between betaxolol and metformin, but direct information about other beta blockers seems to be lacking. 

Nifedipine 10 mg three times daily did not alter the pharmacokinetics of atenolol 100 mg daily, betaxolol, metoprolol 100 mg twice daily 47 or propranolol 80 mg twice daily. A single-dose study also found no pharmacokinetie interaetion between nifedipine and atenolol. However, another study found that nifedipine 10 mg three times daily eaused an inerease in the peak plasma level and AUC of propranolol 80 mg twiee daily of 56% and 23%, respectively. Another study found that the absorption of a single-dose of propranolol appeared to be faster, leading to higher initial eoncentrations, when it was given after nifedipine. Regardless of the pharmacokinetic changes, none of these studies in healthy subjeets found any adverse haemodynamic effects from the eombination of nifedipine and these beta blockers. - ... 

A survey of 15 patients taking beta blockers (acebutolol, atenolol, betaxolol, nadolol, pindolol, propranolol or sotalol) for 6 to 8 weeks found no evidence of changes in antihypertensive effects or bradycardia while they were taking famotidine 40 mg daily. No interaction would be expected, and no special precautions would seem necessary if famotidine is taken with these or any other beta blocker. 

The cardioselective beta blockers would not be expected to affect the beta receptors in the bronchi, but bronchospasm can sometimes occur following their use by asthmatics and others with obstructive airways diseases, particularly if high doses are used. Deterioration of asthma was reported in a patient taking oral betaxolol with theophylline and pranlu-kast, although betaxolol is considered to be highly cardioselective and less likely to cause pulmonary adverse effects than other cardioselective beta blockers. ... 

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