* Q4 EPS $0.58 vs est. $0.54
* Q4 revenue up 6 pct, beats Street
* Sees Q1 EPS $0.50-$0.53 vs est. $0.53
* Shares down as much as 10 percent (Recasts, adds details, analyst comments)
BANGALORE, Feb 2 (Reuters) - Personal-care products maker Nu Skin Enterprises Inc (NUS.N) forecast a conservative first quarter, saying it would be difficult to replicate the success of the first half of 2010 this year, sending its shares down as much as 10 percent.
Provo, Utah-based Nu Skin's shares were down $2.84 at $28.37 on Wednesday making it one of the top losers on the New York Stock Exchange.
"Overall, 2011 will face rather challenging year-over-year comparisons against a year that saw the most successful new product launch in the company's history, performance that will be truly difficult to replicate," Wedbush Securities analyst Rommel Dionisio said.
Nu Skin, which also sells nutritional supplements under its namesake and Pharmanex brands, expects first-quarter earnings of 50-53 cents a share and revenue of $380-$390 million.
Analysts on an average were expecting earnings of 53 cents a share, on revenue of $392 million, according to Thomson Reuters I/B/E/S.
Net income for the October-December quarter was $37.3 million, or 58 cents a share, compared with $30.3 million, or 47 cents a share, a year ago. [ID:nASA01HEI] (Reporting by Aditi Sharma and N.R. Sethuraman in Bangalore; Editing by Unnikrishnan Nair, Roshni Menon)