The UK's blue-chip index fell 0.27 per cent to 6,130 points.
"European markets pulled back from weekly highs as service sector data came in mixed, healthcare stocks dropped and traders pulled positions ahead of Friday’s US jobs report," said CMC Markets analyst Jasper Lawler.
He added: "A downgrade to the global pharmaceuticals industry from ‘positive’ to ‘stable’ by credit rating agency Moody’s sent shares of GlaxoSmithKline, Shire and AstraZeneca to the bottom half of the FTSE 100. Moody’s cited the effect of pricing pressures on earnings which has been a hot-button issue since the rise and fall of hedge fund manager Martin Shkreli who was publically lambasted for price gauging.
AstraZeneca fell 1.79 per cent to 4,000p per share, while GlaxoSmithKline dropped 1.86 per cent to 1,370p per share. Shire fell 3.02 per cent to 3,755p per share.
Whitbread fell 6.15 per cent to 3,800p per share after it reported disappointing sales figures, particularly at its coffee chain Costa Coffee.
Inmarsat also fell substantially after reporting profit to have dropped on weak government spending. Its share price fell 4.24 per cent to 925p.
Tourism based stocks also fell. Carnival was down 3.26 per cent to 3,417p per share, while TUI dropped 3.21 per cent to 1,026p per share.
Merlin Entertainments closed at 451.2p per share, a 2.7 per cent fall, and International Consolidated Airlines fell 2.29 per cent to 533p per share.
But Anglo American was up 1.7 per cent to 533p per share after Deutsche Bank raised its price target for the stock. Glencore was up after UBS did the same for its stock. It closed at 143p per share, a 5.61 per cent rise
Admiral Group was also up 9.03 per cent to 1,919p per share after reporting pre-tax profits up six per cent for 2015.
And CRH was another of the biggest climbers after reporting profits of €1.03bn. It jumped 4.59 per cent to 1,935p per share.
Aerospace engineering group Rolls Royce also rose 5.29 per cent to 716p per share, lifted by a price target upgrade from investment bank Jefferies.