Xalatan Eye Drops
Xalatan Eye Drops
Xalatan Eye Drops are sterile buffered, preserved colorless to slightly yellow solutions of latanoprost with each ml of xalatan contains 50 µg of latanoprost (0.005%). It is supplied as a 2.5 mL solution in a 5 mL bottle. Xalacom which also belong to prostaglandin analogue family consists of Latanoprost and another active ingredients called Timolol which belongs to Beta-blockers Family.
Ingredients of Xalatan Eye Drops
Latanoprost which is a prostaglandin analogue.
Sodium chloride, sodium dihydrogen phosphate monohydrate, disodium hydrogen phosphate anhydrous and water for injection. One drop contains approximately 1.5 μg of latanoprost.
0.02% Benzalkonium chloride.
Mechanism of Action of Xalatan Eye Drops
It reduces the intraocular pressure (IOP) by increasing the outflow of aqueous humor though uveoscleral pathway. Its action starts about 3 after topical administration and the maximum effect is reached after 8 to 12 hours. Duration of action can last for 24 hours. It is used once a day at bedtime.
Absorption and Metabolism
Latanoprost is a prodrug with isopropyl ester which will be hydrolyzed in the cornea through especial enzyme in the cornea called corneal esterase to the biological active drug. After topical administration, its peak concentration in the aqueous humor is reached about 2-3 hours. It is metabolized in the liver by oxidation mechanism and excreted through the kidney
Unused or Unopened bottle should be stored in refrigerator at 2° to 8°C. Opened bottle can be stored at room temperature up to 25°C for 6 weeks and should be away from moisture, heat, and light. Always keep your medications away from children.
Indications of Xalatan
The main indication of xalatan is to decrease the high intraocular pressure by increasing the outflow of aqueous humor through uveoscleral tracts. It is used in Open angle glaucoma, ocular hypertension and normal pressure glaucoma. Its usage in other types of glaucoma such as angle closure, neovascular glaucoma and inflammatory glaucoma is limited.
Side Effects of Xalatan Eye Drops
1- On Cornea
Burning sensation, Blurred of vision which can be temporary after each eye drop or due to dry eyes, eye pain, foreign body sensation, punctuate keratopathy. Sometimes xalatan application can flare up previous Herpes Eye Infection.
2- On Conjunctiva
Conjunctival hyperemia with eye redness, sometimes patient can’t tolerated the redness and this can lead to discontinuation of medication.
3- On Eyelid
Swelling, crusting, itching and pigmentation. This pigmentation that can occur in the eyelid and the skin around the eye can be reversible when the medication is discontinued.
4- On Eyelashes
This is one of the most common side effects of Xalatan. Some patients consider it as an advantage rather than side effect. In fact there is a prostaglandin analogue eye drops similar to Xalatans that is used to enhance eyelashes growth in patients with hypotrichosis and this medication is called Latisse.
After prolong usage of xalatan eye drops which can range from 5 months to years, the eyelashes will show some changes such as increasing in length, thickness, number of the lashes and also increase of the pigmentation. Those eyelashes can have misdirected growth in which they will grow toward the cornea causing injuries to the corneal surface. This complication can be reversible in some cases when the medication is discontinued.
Xalatan eye drops can increase iris pigmentation and a different color of the iris with prolongs use will occur. This pigmentation is irreversible in most of the cases even after discontinuation of medication. These color changes occurs mainly in patients with light iris color and in most of the patients it occurs within the first year of treatment.
6- Iritis and Uveitis
Xalatan eye drops can disrupt the blood ocular barrier which helps to prevent most of the blood components to pass to aqueous humor and vitreous body. This barrier can be disrupted by latanoprost causing cells and protein to appear in aqueous humor and vitreous. It should be used with caution in patients who have history of uveitis.
7- Macular Edema
For the same reason as above and especially in patients who are aphakic and pseudophakic patients with ruptured posterior capsule. Xalatan eye drops can diffuse in these cases to the back surface of the eye, causing disruption of blood-retina barrier. This disruption will cause fluid and cells to diffuse to retina layers, causing macular edema.
8- Allergy to xalatan or one of its components
Signs and symptoms can range from mild to severe and once you have allergic reaction you should stop the medication directly and contact your eye doctor or visit the emergency room as soon as possible. These signs and symptoms are skin rash, red eye, eyelids and lips swelling, eye discharge, difficulty breathing with swelling of tongue and throat.
9- Systemic side effects
Some of the systemic side effects are cough with breathing problems, flu-like symptoms, palpitations, angina pain. Systemic side effects of xalatan eye drops are rare but still dangerous and once you have any of these symptoms you should stop the medication and contact your doctor or the nearest emergency room as soon as possible. Flu-like symptoms such as cough, sneezing, sore throat are the most common systemic symptoms.
Xalatan Warnings and Precautions
1- You should follow the instructions that your eye doctor order regarding your treatment with Xalatan Eye Drops.
2- You should know that xalatan is not a cure for glaucoma; it controls only the high intraocular pressure. Don’t stop your eye drops unless your doctor orders that or you notice any of its side effects and at this case you should contact your eye doctor or emergency room.
3- Follow the instructions for storage.
4- Don’t share this medication and any other medications with any one. Keep your medications for yourself.
5- Don’t use Xalatan Eye Drops when you wear contact lens because it has benzalkonium chloride which can cause discoloration of contact lens and also can be participated as particles in contact lenses, causing corneal erosions. Take off your contact lens, apply the eye drop, wait at least ten to fifteen minutes and then wear your contact lens again.
6- Make sure that the bottle you are using is unopened and is not expired.
7- Xalatan is colorless solution, if its color change, stop using it.
8- In case you are on multiple eye drops, always use five minutes apart between them and always keep the gel or ointment to the last.
9- Before using Xalatan eye drops you should tell your doctor about your:
Medications: Eye drops (especially prostaglandin analogues) or oral, prescription or non prescription.
Diseases: systemic (especially kidney and liver diseases) or ocular diseases (inflammatory ocular diseases, ocular infections, ocular trauma...)
Ocular surgeries: If you had ocular surgery or planning to have.
Allergy: Any allergy you have.
Pregnancy: If you are pregnant or you are planning to be pregnant. Its safety in pregnancy has not been well established.
Breast feeding: Many medications can be excreted through the milk. The excretion of xalatan and its metabolites though the milk still not well known.
10- In this eye drop and all other types of eye drops you should avoid the tip of the bottle from touching your cornea, eyes lashes or even your fingers tips because the tip of the bottle can become contaminated with micro-organisms which can cause ocular infections.
11- In case you miss a dose, you should take it as soon as possible and one eye drop in each eye and once daily.
12- In case you think you are suffering from overdose, you should contact your doctor as soon as possible as overdoses can increase the chance of having side effects.
13- In case you notice any side effects, you should stop the medication and contact your eye doctor or visit the emergency room as soon as possible.