- The drops provide a two-pronged therapeutic approach, lowering the osmolarity of the tear film and providing the electrolytes
needed by the ocular surface, including conjunctival goblet cells for maintenance and repair.
- An omega-3 nutritional supplement for dry eye (TheraTears Nutrition for Dry Eye, Advanced Vision Research) and an antibacterial
eyelid cleanser (SteriLid Eyelid Cleanser, Advanced Vision Research) can be used in combination with sodium CMC 0.25% for
patients with recalcitrant severe dry eye.
Altamonte Springs, FL—The international Dry Eye Workshop (DEWS), in its recently issued final report, stated that sodium carboxymethylcellulose
(CMC) 0.25% lubricating eye drops (TheraTears, Advanced Vision Research Inc.) uniquely mimic the composition of the human
tear film and promote healing of irritation of the ocular surface caused by dry eye. (See related article.)
Dr. Omar has no financial interest in any aspect of this report. Phone: 407/389-0800 E-mail: firstname.lastname@example.org
In the section of the DEWS report dealing with current therapies for dry eye, the panel of specialists stated, "The term 'artificial
tears' is a misnomer for most products that identify themselves as such, because they do not mimic the composition of human
tears. Most [artificial tears] function as lubricants, although some more recent formulations mimic the electrolyte composition
of human tears (TheraTears)."
A bilateral therapeutic approach
In line with this remark, the DEWS report pointed out that osmolarity produces morphologic and biochemical changes in the
corneal and conjunctival epithelium and resultant inflammation of the ocular surface in late cases, conditions that are reversed
by sodium CMC 0.25%. The tear formulation has that effect because of its hypotonicity (i.e., increased volume of water in
relation to the amount of salts), which has been effective at lowering elevated tear film osmolarity with four-times-a-day
dosing. In addition, research indicates that the electrolytes in the tear formulation are biologically active, said Sam Omar,
MD, a cornea specialist in private practice at Advanced Vision Institute, Altamonte Springs, FL, in an interview with Ophthalmology Times.
"Increased tear osmolarity plays a central role and is one of the most sensitive and specific indicators in patients with
dry eye," he explained further. "In conjunction with increased tear film osmolarity, inflammatory mediators create a vicious
cycle that further negatively affects the ocular surface. Sodium CMC 0.25% does a remarkable job of reversing this process
in the patient with dry eye."
Dosing, therefore, provides a two-pronged therapeutic approach, lowering the osmolarity of the tear film and providing the
electrolytes needed by the ocular surface, including conjunctival goblet cells, for maintenance and repair.
"These are the claims to fame of sodium [CMC] 0.25%," Dr. Omar stated. "[Sodium CMC 0.25%] is also a tear formulation that
has been shown in some scientific data to increase goblet cell density.
"The only other drop that has claimed to improve the quality of the tear film is [cyclosporine emulsion (Restasis, Allergan)],
the major obstacles to which are cost, insurance coverage, and the prolonged latency of clinical improvement," he said.
Dr. Omar said he has been using sodium CMC 0.25% for about 2 years. Because of the product's effects, he considers it the
primary therapy for his patients with dry eye, most of whom are postmenopausal women.
When assessing a patient with dry eye, sodium CMC 0.25% is the first treatment he prescribes, Dr. Omar said.
"The reason for this is that I need a product that is going to work relatively quickly to help bolster patient compliance
with the regimen," Dr. Omar said. "If a clinician uses a product that does not subjectively and objectively improve a condition
rapidly, patient compliance and follow-up will suffer. In addition, [sodium CMC 0.25%] has a very good side effect profile."
Dr. Omar said he prefers the preservative-free form of sodium CMC 0.25% because of the quality control in the foil-sealed
packet compared with the bottled formulation.