Latanoprost belongs to a class of medications called prostaglandin analogs. It works to reduce the pressure in the eye by allowing fluid in the eye to flow out of the eye better. It is used to treat people with open-angle glaucoma and intraocular hypertension (increased pressure in the eye). It may also be used to reduce pressure in the eye for people who have chronic angle-closure glaucoma who have had surgical treatment.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are being given this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

The recommended dose of latanoprost is 1 drop to the affected eye(s) once daily, preferably in the evening. This medication should not be used more than once a day.

Ask your doctor or pharmacist to show you the correct way to instill the eye drops. This medication is for external use only. Do not allow the dropper tip of the bottle to touch your eye or other surrounding structures, because this could contaminate the tip with common bacteria known to cause eye infections. Serious damage to the eye may result if you use eye drop solutions that have become contaminated.

Remove contact lenses before putting the drops in your eye(s). They may be reinserted 15 minutes after you have put latanoprost eye drops in your eye.

Latanoprost eye drops may be used with other eye medications intended to reduce pressure inside the eye. If more than one type of eye drop is being applied, use the medications at least 5 minutes apart.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. If you miss a dose, skip the missed dose and continue with your regular dosing schedule. Do not instill a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Before opening, keep the container of eye drops in the fridge, out of direct light. Once the bottle has been opened, keep the eye drops at room temperature. Latanoprost eye drops must be used within 6 weeks after opening the container.

Store this medication out of reach of children.

Latanoprost should not be used by anyone who is allergic to latanoprost or any ingredients of the medication.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• blurred vision, eye irritation, or tearing
• dryness of eye
• burning sensation in the eye
• feeling of "something in eye"
• itchy eye
• longer, thicker, and darker eyelashes
• stinging of eye
• excessively watering eye

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• blurred or wavy vision in the middle of the eye
• changed perception of colour
• cold or flu symptoms, sore throat, fever
• darkening of eyelid skin colour
• discharge from the eye
• double-vision
• eye irritation from eyelashes growing in the wrong direction
• eye pain
• eyelid crusting, redness, swelling, discomfort, or pain
• increase in brown colour in coloured part of eye
• pain in muscles, joints, or back
• redness of eye or inside of eyelid
• sensitivity of eye to light
• signs of eye infection (e.g., blurred vision, pain, redness, tearing, discharge, sensitivity to light)
• skin rash

Stop taking the medication and seek immediate medical attention if any of the following occur:

• angina pectoris or other chest pain
• chest tightness
• increased asthma symptoms (e.g., wheezing, difficulty breathing, noisy breathing)
• severe skin reaction (rash near eye area as well as other areas of the body)
• swelling of the eye
• vision changes with a red and sore or painful eye

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Asthma: Some people with asthma may experience an increase in asthma symptoms, such as shortness of breath, when they use latanoprost or other similar medications. If you have asthma, discuss with your doctor how latanoprost may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Eye changes: Latanoprost may gradually change the colour of the eye, increasing the amount of brown pigment in the iris by increasing the number of melanosomes (pigment granules). The long-term effects on the eye and the chances of injury to the eye are currently unknown. The change in colour may be permanent. This effect has mostly been seen in patients with mixed-coloured eyes (e.g., blue-brown, grey-brown, green-brown, or yellow-brown). In patients with uniformly blue, grey, green, or brown eyes, the change has only rarely been seen. The change in colour occurs slowly, and may not be noticeable for several months to years. Latanoprost has also been reported to cause darkening, thickening, and lengthening of eyelashes, as well as darkening of the eyelid.

Other eye conditions: The safety of using latanoprost eye drops if you have other eye conditions may not be well known. If you have other eye conditions such as uveitis or lens problems, discuss with your doctor how latanoprost may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Kidney or liver function: This medication has not been studied for use by people with impaired kidney or liver function. Latanoprost should be used with caution by these individuals.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while using this medication, contact your doctor immediately.

Breast-feeding: This medication may pass into breast milk. If you are a breast-feeding mother and are using latanoprost, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and efficacy of latanoprost have not been established for use by children.

There may be an interaction between latanoprost and any of the following:

• bimatoprost
• non-steroidal anti-inflammatory medications (NSAIDs; e.g., celecoxib, diclofenac, ibuprofen, naproxen)
• other eye drops
• thimerosal

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.