Side Effects of Xalatan (latanoprost)

Xalatan (latanoprost), a derivative of the chemical, prostaglandin F2-alpha, is used to treat glaucoma. 

Glaucoma is a condition in which the pressure exerted by the liquid within the eyeball (the aqueous humor) is too great. The high pressure damages the optic nerve at the back of the eye. The damage interferes with the ability of the nerve to transmit visual images from the eye to the brain and thus can lead to blindness. 

Prostaglandins control the flow of the aqueous humor out of the eye. Xalatan, by binding to a specific receptor for prostaglandin, increases the flow of aqueous humor out of the eye, thereby reducing the pressure within the eye and reducing the risk of nerve damage and blindness.

When latanoprost and timolol (Timoptic) (a different drug that also is used to treat glaucoma) are used in combination, there is a greater reduction in pressure than when either drug is used alone. 

Common side effects of Xalatan include

• blurred vision,
• redness,
• the sensation of a foreign body in the eye,
• discoloration of the iris,
• itching,
• burning,
• stinging,
• eye dryness,
• increased tearing,
• eye pain,
• other eye-related discomforts, and
• eyelash changes such as increased length, thickness, and number of lashes. 

Serious side effects of Xalatan are rare and include

• conjunctivitis,
• double vision, and
• eye discharge.

Drug interactions of Xalatan include eye drops containing thimerosal, because combining them with Xalatan may cause precipitation of the chemicals within the drops. 

Thimerosal eye drops and Xalatan should be administered at least 5 minutes apart. Combining Xalatan with other prostaglandin eye drops may reduce the effect of Xalatan and may even increase intraocular pressure. 

There are no adequate studies of Xalatan in pregnant women. 

Physicians should use Xalatan during pregnancy only if its benefits are felt to outweigh the potential risks to the fetus. 

It is unknown if Xalatan is secreted into breast milk. Consult your doctor before breastfeeding. 

Between 5% and 15% (between 1 in 20 and 1 in 6) of persons receiving latanoprost for 6 months report at least one side effect localized to the eyes. These side effects included:

• blurred vision,
• redness,
• a sensation of a foreign body,
• discoloration of the iris,
• itching,
• burning, and
• stinging.

Discoloration of the iris begins slowly. It is caused by an increase in the amount of brown pigment in the iris and may be permanent. Other side effects which have been reported less frequently include:

• dryness of the eyes,
• increased tearing,
• eye pain,
• and other eye-related discomfort.

elash changes such as increased length, thickness, and number of lashes may occur. Conjunctivitis, double vision, and eye discharge are rare side effects of latanoprost.

The following adverse reactions were reported in postmarketing experience and are discussed in greater detail in other sections of the label:

• Iris pigmentation changes
• Eyelid skin darkening
• Eyelash changes (increased length, thickness, pigmentation, and number of lashes)
• Intraocular inflammation (iritis/uveitis)
• Macular edema, including cystoid macular edema

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, the adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

Xalatan was studied in three multicenter, randomized, controlled clinical trials. Patients received 50 mcg/mL Xalatan once daily or 5 mg/mL active-comparator (timolol) twice daily. The patient population studied had a mean age of 65±10 years. Seven percent of patients withdrew before the 6-month endpoint.

Table 1: Ocular Adverse Reactions and Ocular Signs/Symptoms Reported by 5-15% of Patients Receiving Latanoprost

Less than 1% of the patients treated with Xalatan required discontinuation of therapy because of intolerance to conjunctival hyperemia.

Table 2: Adverse Reactions That Were Reported in 1-5% of Patients Receiving Latanoprost

The ocular event/signs and symptoms of blepharitis have been identified as “commonly observed” through analysis of clinical trial data.

Postmarketing Experience

The following reactions have been identified during postmarketing use of Xalatan in clinical practice. Because they are reported voluntarily from a population of unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. The reactions, which have been chosen for inclusion due to either their seriousness, frequency of reporting, possible causal connection to Xalatan, or a combination of these factors, include:

Nervous System disorders: Dizziness; headache; toxic epidermal necrolysis

Eye Disorders: Eyelash and vellus hair changes of the eyelid (increased length, thickness, pigmentation, and number of eyelashes); keratitis; corneal edema and erosions; intraocular inflammation (iritis/uveitis); macular edema, including cystoid macular edema; trichiasis; periorbital and lid changes resulting in deepening of the eyelid sulcus; iris cyst; eyelid skin darkening; localised skin reaction on the eyelids; conjunctivitis; pseudopemphigoid of the ocular conjunctiva

Respiratory, Thoracic and Mediastinal Disorders: Asthma and exacerbation of asthma; dyspnea

Skin and Subcutaneous Tissue Disorders: Pruritus

Infections and Infestations: Herpes keratitis

Cardiac Disorders: Angina; palpitations; angina unstable

General Disorders and Administration Site Conditions: Chest pain

In vitro studies have shown that precipitation occurs when eye drops containing thimerosal are mixed with Xalatan. If such drugs are used, they should be administered at least five (5) minutes apart.

The combined use of two or more prostaglandins, or prostaglandin analogs including Xalatan is not recommended. It has been shown that administration of these prostaglandin drug products more than once daily may decrease the IOP lowering effect or cause paradoxical elevations in IOP.