* Q4 net down 61 pct at 4.78 bln forints vs f'cast 11.8 bln
* Revenue to decline from 2013 levels in euro terms-CEO
* Growth in biggest mkt Russia up to 5 pct in rouble terms
* Rising costs to cut operating profit margin in 2014 -CEO
* Shares down 1.7 percent vs 0.1 pct rise in benchmark index (Adds detail, comments, shares)
BUDAPEST, Feb 5 Hungarian drugmaker Richter has flagged a decline in revenue and profit for 2014 after a "very weak" fourth quarter, blaming the glum outlook on exchange-rate effects and rising research and marketing costs.
The company reported a 61 percent fall in quarterly net profit to 4.78 billion forints ($20.9 million), well below analyst expectations of 11.8 billion in a recent survey by financial news website portfolio.hu, as higher costs along with financial and impairment charges swallowed up a rise in revenue.
Richter, which makes gynaecological, cardiovascular and central nervous system drugs, said on Wednesday revenue would decline in euro terms in 2014, due largely to exchange-rate effects, from last year's 1.18 billion euros.
"It is not a joy when we have to say our revenue is expected to shrink, however, exchange-rate developments have a significant role in this," Chief Executive Erik Bogsch told a news conference. He did not specify the extent of the decline.
"Our product portfolio is rather stable, but first we need to compensate for price erosion, which can be done partly with new products or with a growth in sales volumes."
Richter shares traded 1.7 percent lower at 4,450 forints by 0916 GMT, underperforming a 0.1 percent rise in the Budapest blue-chip index.
In its domestic market, which accounted for just 9 percent of revenue last year, Richter expects stagnation in local currency terms. But in Russia, its biggest market, it sees up to 5 percent growth in rouble terms.
Richter did not give a revenue estimate for crisis-hit neighbour Ukraine, where it earned nearly $95 million in 2013.
"It will clearly be negative, but just how much lower, it would be irresponsible to say now," Bogsch said.
In the United States, Richter expects revenue to decline by between 10 and 15 percent in dollar terms, while in China, the world's third-largest pharmaceuticals market, it forecasts a 12 percent increase to 40 million euros this year.
Bogsch said Richter aimed to nearly double sales of its flagship Esmya medicine to treat uterine myoma to 30 million euros this year. The European Commission recently approved the product for a longer treatment period, boosting its prospects.
Bogsch said the company expected its 2014 operating profit margin to drop to between 12 and 13 percent of revenue from 13.8 percent in 2013, due to rising sales and marketing costs and research and development spending.
He said research and development costs would increase to 13 percent of revenue in 2014 from 11.8 percent in 2013, while sales and marketing expenditure was estimated at 31.5 percent of revenue, up from 30.4 percent. (Editing by Jane Merriman and David Holmes)