Product Information
Registration Status: ActiveAZARGA 10MG/ML + 5MG/ML EYE DROPS, SUSPENSION is approved to be sold in Singapore with effective from 2010-05-19. It is marketed by NOVARTIS (SINGAPORE) PTE LTD, with the registration number of SIN13802P.
This product contains Brinzolamide 10mg/mL, and Timolol 5mg/mL in the form of SUSPENSION, STERILE. It is approved for OPHTHALMIC use.
This product is manufactured by S.A. Alcon Couvreur N.V in BELGIUM.
It is a Prescription Only Medicine that can only be obtained from a doctor or a dentist, or a pharmacist with a prescription from a Singapore-registered doctor or dentist.
Description
Brinzolamide is a highly specific, non-competitive, reversible carbonic anhydrase inhibitor. Carbonic anhydrase (CA) is an enzyme found in many tissues of the body including the eye. It catalyzes the reversible reaction involving the hydration of carbon dioxide and the dehydration of carbonic acid. In humans, carbonic anhydrase exists as a number of isoenzymes, the most active being carbonic anhydrase II (CA-II). Inhibition of carbonic anhydrase in the ciliary processes of the eye decreases aqueous humor secretion, presumably by slowing the formation of bicarbonate ions with subsequent reduction in sodium and fluid transport. The result is a reduction in intraocular pressure. Brinzolamide is indicated in the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.
Indication
For the treatment of elevated intraocular pressure in patients with ocular hypertension or open-angle glaucoma.
Mechanism of Action
Brinzolamide is a highly specific inhibitor of CA-II, which is the main CA isoenzyme involved in the secretion of aqueous humor. Inhibition of CA in the ciliary process of the eye slows the formation of bicarbonate, and reduces sodium and fluid transport. This results in a reduction in the rate of aqueous humor secretion and the intraocular pressure. Brinzolamide is absorbed systemically following topical ocular administration. Since it has a high affinity for CA-II, brinzolamide binds extensively to red blood cells, where CA-II is primarily found. As sufficient CA-II activity remains, adverse effects resulting from the systemic inhibition of CA by brinzolamide are not observed. The metabolite N-desethyl brinzolamide is also formed. This metabolite binds to CA and accumulates in red blood cells as well. In the presence of brinzolamide, the metabolite binds mainly to carbonic anhydrase I (CA-I).
Pharmacokinetics
- Absorption
- Absorbed into systemic circulation following topical ocular application
- Distribution
- Metabolism
- Ophthalmic
- Elimination
Active Ingredient/Synonyms
Brinzolamide | Brinzolamide |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.
Description
A beta-adrenergic antagonist similar in action to propranolol. The levo-isomer is the more active. Timolol has been proposed as an antihypertensive, antiarrhythmic, antiangina, and antiglaucoma agent. It is also used in the treatment of migraine disorders and tremor. [PubChem]
Indication
In its oral form it is used to treat high blood pressure and prevent heart attacks, and occasionally to prevent migraine headaches. In its opthalmic form it is used to treat open-angle and occasionally secondary glaucoma.
Mechanism of Action
Like propranolol and nadolol, timolol competes with adrenergic neurotransmitters such as catecholamines for binding at beta(1)-adrenergic receptors in the heart and vascular smooth muscle and beta(2)-receptors in the bronchial and vascular smooth muscle. Beta(1)-receptor blockade results in a decrease in resting and exercise heart rate and cardiac output, a decrease in both systolic and diastolic blood pressure, and, possibly, a reduction in reflex orthostatic hypotension. Beta(2)-blockade results in an increase in peripheral vascular resistance. The exact mechanism whereby timolol reduces ocular pressure is still not known. The most likely action is by decreasing the secretion of aqueous humor.
Pharmacokinetics
- Absorption
- Bioavailability is about 60%
- Distribution
- Metabolism
- Primarily hepatic (80%) via the cytochrome P450 2D6 isoenzyme.
- Elimination
Toxicity
LD50=1190 mg/kg (oral, mice), LD50=900 mg/kg (oral, rat). Symptoms of overdose include drowsiness, vertigo, headache, and atriventricular block.
Active Ingredient/Synonyms
(S)-1-(tert-butylamino)-3-[(4-morpholin-4-yl-1,2,5-thiadiazol-3-yl)oxy]propan-2-ol | Timolol | Timolol anhydrous | Timololo | Timololum | Timolol |
Source of information: Drugbank (External Link). Last updated on: 3rd July 18. *Trade Name used in the content below may not be the same as the HSA-registered product.