* Eisai drops on after soaring 32 pct over the last 2 days * Positive themes about Japan market may continue - analyst By Ayai Tomisawa TOKYO, March 25 (Reuters) - Japan's Nikkei share average edged down on Wednesday morning in choppy trade as U.S. shares languished, but losses were limited by investor appetite for stocks before they go ex-dividend later this week. The Nikkei benchmark fell 0.2 percent to 19,677.45 in mid-morning trade after trading in positive territory earlier. Analysts said that although there are signs that the benchmark has risen sharply over the short period of time, the market may not fall sharply until this Thursday, when most of the stocks go ex-dividend. The Nikkei has added 13 percent since this year and has risen about 5 percent so far this month, reflecting hopes of recovering Japanese corporate earnings and better shareholder returns. In the long-term, investors are seen bullish on the Japanese market, analysts said. "These themes (better earnings and shareholder returns) as well as increasing wages will likely continue attracting foreign investors in the longer term," said Jun Yunoki, a strategist at Nomura Securities, who visited Asian investors earlier this month. "It's a matter of time before the Nikkei reaches 20,000." Japanese blue-chip companies announced wage hikes that topped increases from the year before, following annual wage talks, as requested by Prime Minister Shinzo Abe, who is eager to boost the economy squeezed by last year's sales tax hike. Outperforming the market was Santen Pharmaceutical Co , which jumped as high as 9.2 percent to a record high of 9,180 yen after the drugmaker raised its earnings forecast. Eisai Co dropped 4.8 percent on profit-taking after the drugmaker soared more than 32 percent over the past two days on hopes for the effectiveness of the drug which it co-developed with Biogen Idec Inc. to treat Alzheimer's disease. Exporters were mixed, with Toyota Motor Corp dropping 0.5 percent, Honda Motor Co shedding 0.3 percent and Tokyo Electron rising 0.3 percent. The broader Topix edged down 0.1 percent to 1,585.30 and the JPX-Nikkei Index 400 declined 0.1 percent to 14,409.48.