Studies into off-label uses of ophthalmic drugs can help us understand options for treating problems we commonly see in practice. Two such problemsnight glare after refractive surgery and dry eyehave been the subjects of recent studies into off-label uses.
Solving Night Glare
Alphagan (brimonidine 0.2%, Allergan) has been used for diminishing or eliminating large pupil size related to night vision problems following refractive surgery.
One study showed that Alphagan significantly decreased pupil size under scotopic conditions but not under photopic light.1 Many doctors tell patients to instill one drop 30 minutes before an anticipated need, such as night driving. The effect may last 6-8 hours.
In this study, patients instilled one drop of Alphagan in their eyes. Pupil measurements were taken at 30 minutes, and at four and six hours under scotopic, room and photopic illumination. Researchers compared these measurements with those of the patients baseline without the use of Alphagan.
Unlike pilocarpine, which has many side effects and maintains a miotic pupil in all light, Alphagan maintains a normal pupil in photopic and room illumination. The drug also showed a significant decrease in mydriasis in scotopic illumination at precisely when it is needed.
Data show an average decrease in pupil size of 2mm in dim light after brimonidine use. The effect occurs through stimulation of the alpha2 receptor that operates the gain-control feedback mechanism of the pupil dilator. This causes hyperpolarization and inhibits further norepinephrine release. Alpha-gan does not affect the parasympa- thetic pathway as pilocarpine does. So, Alphagan does not affect the ciliary muscle. It will not induce brow ache, accommodation or miosis.
Loteprednol Etobonate
Alrex (loteprednol etabonate 0.2%, Bausch & Lomb) has been shown to be an effective treatment for dry eye. Recent studies indicate that inflammation is a key component in dry eye. Research shows that T-lymphocytes in the surface epithelial and lacrimal glands of Sjgrens patients and in those with severe dry eye to be 200 to 1,000 times that of normal patients. In the study, 83% of patients showed improvements in symptoms after two weeks of steroid use.2
Other studies have shown methylprednisolone was effective in treating dry eye.3 However, this drugs use was limited due to the chronic nature of dry eye and the risk of long-term steroid use. That changed with the introduction of the soft steroids. New research recommends prescribing Alrex bid for two weeks, then continuing with artificial tears afterward.
A study on Lotemax (loteprednol etabonate 0.5%, Bausch & Lomb) showed a significant reduction in inflammatory signs and symptoms in dry eye patients and a safety profile equal to that of a placebo.4 Another study showed that Alrex had a complication and side effect rate similar to the placebo.
Using loteprednol off-label for dry eye gives you the anti-inflammatory effect of a steroid with the low risk of a soft steroid. This may yet be an ideal medication for dry eye treatment.
Dr. Karpecki has no financial interest in the products mentioned, although he is a consultant to Bausch & Lomb Surgical.
1. McDonald JE 2nd, El-Moatassem Kotb AM, Decker BB. Effect of brimonidine tartrate ophthalmic solution 0.2% on pupil size in normal eyes under different luminance conditions. J Cataract Refract Surg. 2001 Apr;27(4):560-4.1.
2. Prabhasawat P, Tseng SC. Frequent association of delayed tear clearance in ocular irritation. Br J Ophthal 1998 Jun;82:666-75.
3. Marsh P, Pflugfelder SC. Topical non-preserved methylprednisolone therapy for keratoconjunctivitis sicca in Sjgrens syndrome. Ophthalmology 1999 Apr;106(4):8111-6.
4. Stewart R, Horwitz B, Howes J, et al. Double-masked, placebo-controlled evaluation of loteprednol etabonate 0.5% for postoperative inflammation. Loteprednol Etabonate Postoperative Inflammation Study Group 1. J Cataract Refract Surg. 1998 Nov;24(11):1480-9.
