Timox-D contains two active ingredients in its formula: Dorzolamide hydrochloride and Timolol maleate. Both components of the formula decrease elevated intraocular pressure by reducing the production of aqueous humor through different mechanisms of action. Dorzolamide is a carbonic anhydrase inhibitor for topical ophthalmic use. Carbonic anhydrase is an enzyme found in many tissues in the body, including the eye. When dorzolamide is applied topically, it reaches the circulation after chronic administrations. It binds moderately to plasma proteins and is metabolized in the liver to a metabolite that is also active. It is mainly eliminated via the urine as a free drug and as a metabolite. Timolol is a beta1, beta2-nonselective beta-adrenergic receptor blocking agent, lacking significant intrinsic sympathomimetic activity, direct myocardial depressant or local anesthetic (membrane stabilizer). The hypotensive mechanism of action of ophthalmic beta-blockers is not yet known, but appears to be related to reduced aqueous humor formation, as demonstrated by tomography and fluorometry. An additional mechanism may be a slight increase in the reflux or drainage of that aqueous humor. Timolol has no intrinsic agonist or local anesthetic activity. However, its systemic absorption can occur through the tear ducts; therefore, it should be used with caution in patients with asthma, emphysema, congestive heart failure, diabetes, and superior heart block. The onset of action of timolol is observed 30 minutes after a single dose is administered.
The duration of action of timodol ophthalmic solution can be maintained for 24 hours following single administration, with a significant decrease in intraocular pressure. The combined effect of these two active ingredients produces a further reduction in intraocular pressure when compared with that obtained with any of these components administered separately. Topical ocular administration of Timox-D reduces elevated intraocular pressure, regardless of the presence or absence of glaucoma. Timox-D reduces elevated intraocular pressure without the common side effects of parasympathomimetic antiglaucomatous agents, such as accommodation spasm or miosis.
Each ml contains:
Timolol (Maleate) 5 mg
Dorzolamide (HCl) 20 mg
Excipients and purified water C.S.P. 1 ml
Administration and posology
Administration route: Ophthalmic.
The recommended dosage is 1 drop of Timox-D in the affected eye (s) every 12 hours.
Keep at a temperature between 15 °C and 25 °C. Protect from freezing.
Box containing a dropper bottle with 5 ml of solution.
Timox-D ophthalmic solution is indicated for the treatment of elevated intraocular pressure (IOP) in patients with ocular hypertension, open-angle glaucoma, pseudoexfoliative glaucoma, or other secondary open-angle glaucomas when local treatment with a combination of an inhibitor is indicated. of carbonic anhydrase and a beta-adrenergic receptor blocker.
Burning sensation, blurred vision, altered taste, conjunctival hyperemia, superficial keratitis, itchy eyes, eye pain, corneal erosion, tearing may be present.
The combination dorzolamide hydrochloride – timolol maleate was used concomitantly with the following systemic products, with no evidence of unfavorable interactions: ACE inhibitors, calcium channel blockers, diuretics, nonsteroidal anti-inflammatory drugs (including acetylsalicylic acid) and hormones (estrogens, insulin , thyroxine). However, there may be additive effects and marked hypotension and / or bradycardia when timolol maleate is administered in ophthalmic solution together with calcium channel blockers, substances that cause catecholamine depletion or beta-adrenergic blockers. Enhanced systemic beta block has been reported during combination treatment with quinidine and timolol, probably due to the fact that quinidine inhibits timolol metabolism through the enzyme P-450 CYP2D6. Dorzolamide hydrochloride in ophthalmic solution has not been associated with acid-base balance disorders. However, these disorders have been reported with oral carbonic anhydrase inhibitors and, in certain cases, have produced drug interactions (eg, toxicity associated with the administration of high doses of salicylates). Consequently, this possibility and such interactions should be considered in patients treated with Timox-D.
Timox-D is contraindicated in patients with hypersensitivity to any of the components of the formula, bronchial asthma or a history of bronchial asthma or severe chronic obstructive pulmonary disease. Sinus bradycardia, second or third degree atrioventricular block, and overt heart failure.