Cosopt general information
What is Cosopt used for?
Cosopt eye drops are used to treat raised intraocular pressure (IOP), which is a build up of fluid within the eye called aqueous humour that causes increased pressure within the eye and can lead to damage to the optic nerve and blindness, if allowed to progress untreated. Cosopt eye drops 2%/0.5% are used to lower raised IOP in several conditions including ocular hypertension, in which there is raised IOP but no damage to the optic nerve or loss of field of vision; open-angle glaucoma, which is the most common form of glaucoma, in which there is raised IOP and gradual loss of field of vision and this can be primary glaucoma (directly related to a gradual increase of IOP) or secondary glaucoma (due to another cause, such as injury). Cosopt eye drops are a combination medication suitable for those who are already using both medications concomitantly and also if monotherapy with a single medication is not providing sufficient improvement.
How does Cosopt work?
Cosopt eye drops are a combination medication containing dorzolamide, a carbonic anhydrase inhibitor, and timolol, a beta-blocker. Eye fluid (aqueous humour) is produced in the ciliary processes of the eye, by filtration from the capillaries (small blood vessels) in the eye and drains from the eye into the bloodstream through the sieve-like trabecular meshwork. Raised intraocular pressure (IOP) is usually caused either by over production of eye fluid, or a blockage in the drainage of the fluid. Carbonic anhydrase is an enzyme that is found in several tissues in the body, including the ciliary processes of the eye. Dorzolamide in Cosopt eye drops inhibits carbonic anhydrase in the ciliary processes, which interferes with the formation of bicarbonate ions, reduces sodium and fluid transport, and ultimately slows down the filtration process, resulting in decreased secretion of aqueous humour into the eye. Timolol in Cosopt eye drops acts by blocking the beta receptors on the cells of the ciliary processes and this action is thought to contribute to reduced aqueous formation. The combination of the two drugs in Cosopt eye drops results in reduction in intraocular pressure (IOP), to a greater extent than either drug administered alone, which relieves pressure on the optic nerve and this can prevent loss of sight due to increased IOP.
What does Cosopt contain?
Cosopt eye drops contain the active ingredients dorzolamide hydrochloride (20mg/ml or 2%) and timolol maleate (5mg/ml or 0.5%). They also contain sodium citrate, hydroxyethylcellulose, sodium hydroxide, mannitol, water for injection, and benzalkonium chloride (0.0075%) as preservative.
Treating glaucoma with Cosopt
Cosopt eye drops contain dorzolamide, a carbonic anhydrase inhibitor, and and timolol, a beta-blocker that work together, by different and synergistic mechanisms, to reduce production of aqueous humour (eye fluid) by the ciliary processes of the eye reducing intraocular pressure (IOP) that can cause glaucoma. Although aqueous humour is important for maintaining normal eye pressure and providing nutrients for the eye, increased production or decreased drainage from the eye increases IOP, which can cause damage to the optic nerve fibres that lead out of the back of the eye to the brain and may lead gradual loss of sight. This starts with loss of peripheral vision and eventually to total blindness in that eye. Cosopt eye drops help restore the balance in the flow of fluid into and out of the eye reducing IOP and reducing the risk of damage to the optic nerve, which helps prevent loss of sight that can happen if glaucoma progresses untreated.
What are the side effects of Cosopt?
The most commonly reported side effects when taking Cosopt include: burning, stinging, itching eyes, conjunctivitis, corneal erosion, watering of the eye(s), redness of the eye(s), inflammation and swelling of the eyelids(s), eye pain, blurred vision, crusting of the eyelids, nausea, bitter taste, headache, tiredness, weakness.
When should Cosopt not be used?
You should not use Cosopt eye drops if you:
- are allergic to dorzolamide or timolol or any ingredients in Cosopt eye drops
- have asthma, or a history of asthma, or other obstructive lung disorders
- have certain heart conditions, including bradycardia (very slow heart rate), irregular heart beat, or uncontrolled heart failure
- are pregnant or are breastfeeding
- have kidney or liver disease
- are taking medicines that interact with Cosopt, including: other beta-blockers for high blood pressure or heart conditions, the antiarrhythmic quinidine, calcium channel blockers like amlodipine, SSRI antidepressants
How should Cosopt be used?
You should take your Cosopt eye drops by applying one drop into the affected eye twice daily. If you are wearing contact lenses, you should remove them before applying your Cosopt eye drops and then replace them at least 15 minutes after applying your drops. You should continue to use your Cosopt eye drops daily for as long as recommended by your doctor, as they will help maintain normal eye pressure but will not cure glaucoma.
How long should you use Cosopt?
You should continue to use your Cosopt eye drops daily for as long as recommended by your doctor, as they will help maintain normal eye pressure but will not cure glaucoma.
Missed dose of Cosopt
If you miss a dose of Cosopt eye drops take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose. Do not take a double dose.
How should Cosopt be stored?
You should store your Cosopt eye drops in a cool place where the temperature stays below 30°C and always replace the top on the bottle to prevent contamination. Discard the bottle of Cosopt eye drops 4 weeks after opening.