Description
Betaxolol Pharmacodynamics
A selective beta1-adrenoblocker without intrinsic sympathomimetic activity. It has practically no membrane stabilizing (local anesthetic effect).
When used topically, betaxolol reduces intraocular pressure by reducing intraocular fluid production.
Betaxolol may improve ocular circulation (perfusion). It does not cause hemeralopia (unlike myotics).
The onset of hypotensive effect is observed 30 min after injection, time of maximum effect is 2 hours. After single instillation the effect on ophthalmotonus lasts for 12 hours.
Indications
Used to reduce intraocular pressure as monotherapy or in combination with other drugs:
– In ocular hypertension
– in open angle glaucoma
Contraindications
Hypersensitivity to the drug components, sinus bradycardia, sinus node weakness syndrome, II-III degree atrioventricular blockade, cardiogenic shock, severe forms of chronic obstructive pulmonary disease, severe forms of bronchial asthma (including anamnesis), children under 18 years of age.
Caution.
– In patients using other beta-adrenoblockers (especially systemic) due to the risk of cumulative potential effect on intraocular pressure and adverse systemic effects.
– In patients with unstable angina pectoris, 1st degree heart block, hypotension (tendency to bradycardia), coronary heart disease, heart failure.
– In patients with severe peripheral circulatory disorders (severe forms of Raynaud’s disease or Raynaud’s syndrome).
– In patients with mild/moderate forms of bronchial asthma (including history), patients with mild/moderate forms of chronic obstructive pulmonary disease
– In patients with diabetes mellitus, especially unstable (beta-adrenoblockers may mask symptoms of acute hypoglycemia).
– In patients with thyrotoxicosis (beta-adrenoblockers may mask symptoms of hyperthyroidism).
– Patients with dry eye syndrome, corneal disease or tear film formation disorders.
– In patients with closed-angle glaucoma (only in combination with myotics).
– Patients with a history of atopy or anaphylactic reactions.
– In patients with myasthenia gravis (beta-adrenoblockers may increase symptoms).
– In patients with pheochromocytoma.
– In patients after filtration procedures (due to the possibility of vascular detachment).
Administration during pregnancy and lactation
There is no sufficient experience of using the drug during pregnancy and lactation.
Administration during pregnancy and lactation is possible only in case when potential benefit for mother exceeds possible risk for fetus and child. When oral administration of ?-adrenoblockers during pregnancy, there is a risk of delayed intrauterine development of the fetus and development of signs of adrenoreceptor blockade. If, however, the drug was used before delivery, the newborn should be closely monitored during the first days of life.
A small amount of betaxolol penetrates into breast milk, but development of clinical symptoms of ?-adrenoreceptor blockade is unlikely if the drug is used in therapeutic doses.
Dosage and administration method
- Topically. To adults (including elderly patients) into conjunctival sac 1 drop 2 times a day; during the first month the treatment is carried out under control of intraocular pressure.
- To reduce systemic side effects, close the eyes carefully after injection and do not blink.
- Do not open your eyes for two minutes to allow for better absorption of the drug
- The duration of treatment is at the discretion of the attending physician.
