Pharmacological properties Xalacom Eye Drops:
combined and myotic antiglaucoma drug containing latanoprost and timolol maleate. The mechanism of reduction of elevated intraocular pressure in these components is different, that provides an additional reduction in intraocular pressure compared with the effect of which is achieved using each of these components separately.
Latanoprost – a prostaglandin analogue F2α-selective agonist is a prostaglandin F (FP) receptors and lowers intraocular pressure by increasing outflow of aqueous humor. The main mechanism of action is associated with an increase in uveoscleral outflow. Latanoprost has no significant effect on the production of aqueous humor and does not affect the blood aqueous barrier.
Timolol is a β1-blocker, and β2-adrenergic receptors (nonselective), has no significant intrinsic sympathomimetic activity, has no direct depressive effect on the myocardium and has no membrane stabilizing properties. The action of timolol associated with decreased formation of aqueous humor in the ciliary epithelium.
Effect of the drug Xalacom Eye Drops occurs within the first hours after application, and the maximum effect was observed for 6-8 hours
Latanoprost is well into the cornea, this is accompanied by its hydrolysis to a biologically active form – latanoprost acid. The maximum concentration in the aqueous humor is reached about 2 hours after topical drug application. Distributed mainly in the anterior chamber of the eye, the conjunctiva and eyelids. Only a small number of latanoprost reaching the back of the camera. In the acid of latanoprost eye tissues practically not metabolized; metabolism occurs primarily in the liver. In humans, the half-life of latanoprost acid was 17 min. The main metabolites have no or weak biological activity and are derived mainly from urine.
The maximum concentration of timolol in the aqueous humor is reached about the eye 1 part of the dose is systematically absorbed and maximum plasma concentration achieved within 10-20 minutes after topical application of 1 drop in each eye one time per day (300 mg daily). The half-life of timolol in plasma is approximately 6 hours Timolol is extensively metabolised in the liver. Metabolites, as well as some unchanged timolol excreted in the urine.
Indications Xalacom Eye Drops:
The drug is designed to reduce elevated intraocular pressure in patients with open angle glaucoma and elevated IOP.
USE Xalacom Eye Drops:
Adults, including elderly patients, prescribed by a drop in patient eye 1 time per day in the morning. If you have missed a dose, further treatment should be continued using the next scheduled dose. If the patient is assigned more than one drug for topical ophthalmic about the disease, these drugs should be used at intervals of not less than 5 minutes.
Contraindications Xalacom Eye Drops:
asthma or asthma attacks point to a history of severe COPD, sinus bradycardia, AV-block II-III degree, symptomatic heart failure, cardiogenic shock, hypersensitivity to the drug, pregnancy and breast-feeding, children’s age.
SIDE EFFECTS Xalacom Eye Drops:
a feeling of a foreign body in eye, burning, itching, conjunctival hyperemia, blepharitis, corneal damage, transient epithelial erosion point (in most cases are asymptomatic), increased pigmentation of the iris, headache, rare – rash on the skin.
SPECIAL INSTRUCTIONS Xalacom Eye Drops:
To date, no data on the use of the drug in inflammatory eye diseases, inflammatory, neovascular, congenital glaucoma and closed-, and there is little or no experience using the product in open-angle glaucoma in patients with pseudophakia, as well as pigmentary glaucoma. Therefore, under these conditions Xalacom recommended be used with caution.
The drug does not have or had little effect on the pupil, yet there are no data on the effects of the drug at the time of an acute attack of angle-closure glaucoma, the drug should be used with caution in this disease.
Xalacom contains benzalkonium chloride, which can be absorbed by contact lenses. Therefore, before instillation of eye drops contact lenses should be removed, they can be inserted only after 15 minutes after instillation.
As with other medicines for local use in ophthalmology, and instillation of eye drops may temporarily appear blurred vision.
Interactions Xalacom Eye Drops:
There is the possibility of additive effects, which can cause hypotension and / or marked bradycardia when eye drops with timolol are used concurrently with calcium channel blockers, drugs that reduce the activity of catecholamines, adrenergic β-blockers, as well as with antiarrhythmic drugs (including amiodarone and quinidine), cardiac glycosides from digitalis group, holinomimetikami, narcotic analgesics and monoamine oxidase inhibitors.
Topical application of two blockers of β-blockers or prostaglandin-two drugs are not recommended.
Although Xalacom when used as monotherapy has little effect or no effect on pupil size, mydriasis sometimes there were cases when the drug was used with epinephrine.
Β-adrenergic blockers may increase the hypoglycemic effect of antidiabetic agents.
OVERDOSAGE Xalacom Eye Drops:
In addition to eye irritation and redness of the conjunctiva of other side effects from the eye or systemic side effects of overdose of latanoprost have been identified. For timolol overdose is characterized by such symptoms – bradycardia, hypotension, bronchospasm and cardiac arrest. If you have the above symptoms shown symptomatic and supportive therapy. Tests have shown that timolol poorly displayed in hemodialysis. If latanoprost is accidentally taken by mouth, be aware that it undergoes extensive metabolism on first pass through the liver.
