NEW YORK -- Option traders are looking for another quick buck in Abbott Laboratories(ABT) - Get Report

OptionMonster's Heat Seeker system detected heavy activity in the April 46 calls Wednesday, with large blocks mostly purchased for 55 cents to 75 cents. More than 9,300 changed hands by the closing bell, eclipsing previous open interest of 1,238 contracts. 

Long calls lock in the price where investors can buy a stock, allowing them to position for a rally with limited risk. The low cost of the options can also generate significant leverage on a percentage basis. 

The March 47 calls, for instance, were bought for 38 cents on March 11. They almost doubled to 63 cents the next day as shares inched higher and nearly tripled the following week. 

Abbott pulled back later that month, only to find support at $45.50 by last week. It ended Wednesday's session up 0.91% to $46.61. Earnings are due on April 22, after the most recent contracts expire, so the buyers are looking for a quick move higher before the news. 

Overall option volume in the name was nine times greater than average Wednesday, with calls accounting for a bullish 77% of the total.

-- Written by David Russell of 

OptionMonster

Russell has no positions in the stocks mentioned.