Healthcare stocks drag down Wall Street
(Close): Shares in healthcare companies dragged Wall Street lower, even as rising oil prices lifted energy stocks.
The tech-heavy Nasdaq index was 7.98 lower at 5213.14.
The price of Brent crude rose 2.1% to $45.18 a barrel, while US crude was 2.6% higher at $42.87.
The news lifted the shares of oil companies, with Dow component Exxon Mobil up 1.3% and Chevron up 0.66%.
Shares of Bristol-Myers continued to tumble on Monday, after losing ground last week following an announcement that the company's new lung cancer drug had failed a key test. The company fell 4.8% on Monday.
"This is a natural pause for reflection by the markets. Everyone is sitting there saying 'Holy cow, what did we do?'," said Brad McMillan, chief investment officer at Commonwealth Financial Network.
Shares in Walmart dropped 0.6% after the retail giant announced it was buying online retailer Jet.com for about $3bn.
Messaging company Twilio jumped 2.5% ahead of the release of its quarterly earnings. The company released its first earnings report as a public company after markets closed.