Latanoprost Dosing and Treatment Guidelines
Latanoprost should be administered as one drop (1.5 μg) of 0.005% solution in the affected eye(s) once daily in the evening. 1
Dosing Regimen
Administer latanoprost once daily in the evening only - the IOP-lowering effect lasts 20-24 hours after a single dose, making once-daily dosing optimal. 1, 2
Do not exceed once-daily dosing - administering prostaglandin analogs more than once daily may paradoxically decrease the IOP-lowering effect or cause elevations in IOP. 1
If a dose is missed, continue with the next scheduled dose - do not double up on doses. 1
Avoid combining two or more prostaglandins or prostaglandin analogs - concurrent use is not recommended. 1
Timing of Effect
IOP reduction begins 3-4 hours after administration with maximum effect reached at 8-12 hours post-dose. 1
Efficacy is maintained long-term - clinical trials demonstrate sustained IOP reduction over treatment periods of 1-2 years. 3
Expected IOP Reduction
Latanoprost reduces diurnal IOP by 22-39% over 1-12 months of treatment in patients with open-angle glaucoma or ocular hypertension. 3
Mean IOP reduction is approximately 6-7.5 mmHg from baseline pressures around 22-24 mmHg. 4, 5
Position as First-Line Therapy
The American Academy of Ophthalmology recommends prostaglandin analogs, including latanoprost, as among the most efficacious first-line medications for lowering IOP in open-angle glaucoma and ocular hypertension. 6
Latanoprost is generally as effective as bimatoprost or travoprost, though bimatoprost may achieve slightly higher efficacy in IOP reduction. 6
Latanoprost has a favorable tolerability profile compared to other prostaglandin analogs according to the American Academy of Ophthalmology. 6
Combination Therapy
When administering multiple topical ophthalmic drugs, wait at least 5 minutes between different eye drops to prevent washout and ensure proper absorption. 1, 7
Fixed combination therapy of latanoprost with timolol provides better IOP-lowering effects than either component alone for patients requiring multiple medications. 6, 3
Latanoprost shows significant additive effects when combined with timolol, dorzolamide, brimonidine, or pilocarpine. 3
Common Side Effects
Conjunctival hyperemia (3-15% of patients) and iris color change (2-9% of patients) are the most common drug-related ocular events, typically mild to moderate. 3
Iris pigmentation changes may be permanent - approximately 30% of patients, especially those with non-homogeneous eye color, may experience permanent darkening of the iris. Patients must be warned of this risk before beginning treatment. 8
Unlike timolol, latanoprost induces minimal systemic adverse events - no cardiopulmonary effects are associated with latanoprost. 3, 2
Special Populations
Pregnancy Category C - the American Academy of Ophthalmology notes that most ophthalmologists avoid prostaglandins during pregnancy due to theoretical risk of premature labor. 6
May be considered during breastfeeding according to the American Academy of Ophthalmology. 6
Critical Pitfalls to Avoid
Never administer latanoprost more than once daily - this reduces efficacy or causes paradoxical IOP elevations. 1
Do not use two prostaglandin analogs concurrently - combined use is not recommended. 1
Do not delay restarting latanoprost while waiting for ophthalmology consultation in patients with established glaucoma, as untreated glaucoma can lead to irreversible vision loss. 7
Ensure proper spacing between different eye drops - inadequate time between medications leads to washout and reduced efficacy. 1, 7