**1. Introduction**

Recent years, patients with asthenopia increased, because many people are engaged in visual display terminal (VDT) work and are using a portable terminal for example smartphone. The causes of asthenopia are dry eye [1, 2], lack of correction for hyperopia or presbyopia, overcorrection for myopia by contact lens or glasses for example. Eye treatment for these causes does not improve asthenopia in some cases. On the other hand, patients with asthenopia sometimes complain of systemic symptoms such as headache, stiff shoulder, nausea and fatigue. Symptoms by VDT work are serious problems in Japan, so Ministry of Health, Labor and Welfare established guideline for Occupational Health Environmental Management in 2002 [3]. In this guideline, at first, improvement of environment for VDT is necessary, and in serious cases patients should see clinical ophthalmologists. In questionnaire results in 2003 in Japan, many ophthalmologists prescribe glasses for near work or tear drop or Vitamin B12 eye drop to reduce asthenopia from VDT work [4].

Adenosine triphosphate disodium hydrate (ATP-2Na) is internal medicine which approved for asthenopia from the results of multicenter clinical researches or double blind clinical researches in 1970~1990 in Japan [5–7]. In this study, we researched the effect and the safety of ATP-2Na for present asthenopia.
