Latanoprost is absorbed well through the cornea and completely hydrolysed to the active latanoprost acid. Highest concentrations of the acid in the aqueous humour are reached two hours after application, lowering of intraocular pressure starts after 3 to 4 hours, the highest effect is found after 8 to 12 hours, and its action lasts at least 24 hours. When latanoprost acid reaches the circulation, it is quickly metabolised in the liver by beta oxidation to 1,2-dinor- and 1,2,3,4-tetranor-latanoprost acid; blood plasma half life is only 17 minutes. The metabolites are mainly excreted via the kidney.  
Visine and many other over-the-counter (OTC) eye drops are not good choices for the treatment of eye allergies . Many OTC eye drops contain topical decongestants, such as naphazoline and tetrahydrozoline, which act to decrease redness of the eyes. Some OTC eye drops combine topical decongestants and topical antihistamines, such as found in Visine-A and Opcon-A. While these various eye drops are effective for the short-term relief of eye redness, as well as eye itching when the topical antihistamine is added, the long-term use of topical decongestants can lead to side effects.
This information should not be used to decide whether or not to take Pred Forte or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Pred Forte. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.