Latanoprost

Pronunciation

Pronunciation: lah-TAN-oh-prahst
Class: Ophthalmic, Prostaglandin agonist

Trade Names

Xalatan
- Ophthalmic solution 0.005%

Pharmacology

Prostaglandin F analog that reduces IOP by increasing the output of aqueous humor.

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Pharmacokinetics

Absorption

Absorbed through the cornea where the prodrug is hydrolyzed to the active acid drug. Peak concentration in the aqueous humor is reached about 2 h after topical application.

Distribution

Vd is about 0.16 L/kg.

Metabolism

Prodrug is hydrolyzed by esterases in the cornea to biologically active acid. The active drug reaching the systemic circulation is metabolized in the liver.

Elimination

Systemic Cl is about 7 mL/min/kg. Metabolites are primarily excreted by the kidneys.

Indications and Usage

For reduction of elevated IOP in patients with open-angle glaucoma or ocular hypertension.

Contraindications

Standard considerations.

Dosage and Administration

1 drop (1.5 mcg) in affected eye(s) once daily in the evening.

General Advice

  • For topical ophthalmic use only. Not for injection into the eye.
  • May be used alone or in combination with other topical ophthalmic drugs to lower IOP.
  • Do not exceed once daily dose. Administering more frequently than once daily may decrease the IOP-lowering effect.
  • If using other topical ophthalmic drugs, separate each medication by at least 5 min.

Storage/Stability

Store unopened bottle in refrigerator (36° to 46°F). Once opened, bottle can be stored at room temperature up to 77°F for 6 wk. Keep container tightly closed and protected from light.

Drug Interactions

Thimerosal

Precipitation occurs when eye drops containing thimerosal are mixed with latanoprost. If such drugs are used, administer with an interval of at least 5 min between applications.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Angina pectoris, chest pain (1% to 2%).

Dermatologic

Rash/allergic skin reaction (1% to 2%); toxic epidermal necrolysis (postmarketing).

EENT

Blurred vision, burning, conjunctival hyperemia, foreign body sensation, increased pigmentation of the iris, itching, punctate epithelial keratopathy, stinging (5% to 15%); dry eye, excessive tearing, eye phobia, eye pain, lid crusting, lid edema, lid erythema, lid discomfort/pain, photophobia (1% to 4%); corneal edema and erosions, eyelash and vellus hair changes (including increased length, thickness, pigmentation, and number), eyelid skin darkening, herpes keratitis, intraocular inflammation (iritis/uveitis), keratitis, macular edema (including cystoid macular edema), misdirected eyelashes (postmarketing).

Respiratory

Upper respiratory tract infection, cold, flu (4%); asthma/exacerbation of asthma, dyspnea (postmarketing).

Miscellaneous

Muscle/joint/back pain (1% to 2%).

Precautions

Pregnancy

Category C .

Lactation

Undetermined.

Children

Safety and efficacy not established.

Special Risk Patients

Use caution in patients with active intraocular inflammation (eg, iritis, uveitis).

Eye pigmentation

Changes to pigmented tissue (eg, iris, periorbital tissue [eyelid], eyelashes) may occur.

Macular edema

Macular edema, including cystoid macular edema, may occur.

Patient Information

  • Advise patient that usual dose is 1 drop in the affected eye(s) once daily in the evening.
  • Caution patient not to instill more often than once daily. More frequent use may decrease effectiveness of the medication.
  • Teach patient proper technique for instilling eye drops: Wash hands; do not allow dropper to touch eye; tilt head back, look up; pull lower eyelid down; instill prescribed number of drops. Close eye for 1 to 2 min and apply gentle pressure to bridge of nose. Do not rub eye.
  • Advise patient that if more than 1 topical ophthalmic drug is being used, administer the drugs at least 5 min apart.
  • Advise patient who wears contact lenses to remove lenses before instilling latanoprost, and to wait at least 15 min after instilling eye drop before reinserting lenses.
  • Inform patient that this medication may cause a gradual increase in brown pigment in the pupil that may slowly change eye color and may be permanent.
  • Inform patient that this medication may also cause eyelid skin darkening and increases in length, thickness, color, and number of eyelashes, but that these changes may be reversible after discontinuing treatment with latanoprost. Advise patient that if only 1 eye is being treated and these changes occur, the treated eye may look different that the untreated eye.
  • Advise patient to contact the eye doctor if eye or eyelid inflammation is noted, if eye injury occurs, or if planning eye surgery.
  • Remind patient that eye examinations and measurement of IOP will be necessary while using this medication and to keep appointments.

Copyright © 2009 Wolters Kluwer Health.

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