U.S. stocks rose on Tuesday, lifting the S&P 500 to a record high, boosted by healthcare after Actavis' acquisition of Allergan triggered bullish analyst notes.

Further support for equities came from U.S. producer prices that kept intact a trend of benign inflation and from higher homebuilder sentiment in November, while German analyst and investor sentiment advanced this month for the first time in almost a year.

The S&P 500 has risen in seven of the past eight sessions, but its largest gain was of less than 0.4 percent and overall volume has been low. The index gains on Tuesday stopped right at the 2,050 level.

Allergan (AGN.N) on Monday accepted a $66 billion takeover bid from Actavis Plc (ACT.N) in cash and stock. At least two analysts raised Actavis' price target, one to as high as $300. Actavis shares rose Tuesday 5.3 percent to $261.16 as the top percentage gainer on the S&P 500.

"There is more space for M&A, companies are looking for areas to have growth," said Bruce Zaro, chief technical strategist at Bolton Global Asset Management in Boston.

"Healthcare stocks are doing well, but not as a defensive play, and it is a positive that stock prices are strong and stocks are being used as currency," he said.

At 10:45 a.m. EST (1545 GMT) the Dow Jones industrial average .DJI rose 21.65 points, or 0.12 percent, to 17,669.4, the S&P 500 .SPX gained 6.41 points, or 0.31 percent, to 2,047.73 and the Nasdaq Composite .IXIC added 23.38 points, or 0.5 percent, to 4,694.38.

The largest decliner on the S&P was Urban Outfitters (URBN.O), down 8.8 percent the day after posting earnings.

Solar company SunEdison (SUNE.N) rose 26.2 percent to $20.96 as it announced that, together with its unit TerraForm Power (TERP.O), it would buy First Wind for $2.4 billion to enter the U.S. wind power market. TerraForm shares jumped 26 percent to $32.57.

Chinese solar company JA Solar Holdings (JASO.O) reported its fourth straight quarterly profit, sending its shares up 5.6 percent.

CytRx Corp (CYTR.O) shares fell 7.6 percent to $2.55 after the drugmaker said the U.S. Food and Drug Administration placed a partial hold on clinical trials of its experimental cancer drug after a patient died.

Advancing issues outnumbered declining ones on the NYSE by 1,878 to 1,005, for a 1.87-to-1 ratio on the upside; on the Nasdaq, 1,672 issues rose and 830 fell for a 2.01-to-1 ratio.

The S&P 500 was posting 51 new 52-week highs and 1 new low; the Nasdaq Composite was recording 64 new highs and 30 new lows.