GlaxoSmithKline's shares are still up 7% following the tie-up announced with Pfizer.
The company has said that the deal will save costs and this looks likely to have an impact on staff.
Emma Walmsley, chief executive of Glaxo, said: "Obviously there's going to be some impact on people. That's something we are working through and we will certainly be talking to our employees before we start talking about that in any way publicly."
More on the plans announced earlier by GlaxoSmithKline to link its consumer health business with Pfizer and spin it off in three years.
The separation will take away the steady cash flows of the consumer business, meaning there’s more pressure on the men and women in white coats to deliver the next generation of blockbusters. However, the potential to shift significant amounts of debt onto the cash generative consumer business should take the strain off the balance sheet, and thus buy valuable time for the pipeline to deliver. There’s also the fact that as a specialist pharma group, investors can be more confident GSK can get better results from the labs.
GlaxoSmithKline has faced calls from investors in the past to spin off the consumer healthcare division, George Salmon, analyst at Hargreaves Lansdown explains.
The previous chief executive, Sir Andrew Witty, did not respond to the calls.
So today's announcement to spin off the division is a "surprise".
"Under Andrew Witty’s leadership, calls for GSK to spin off the consumer healthcare businesses fell on deaf ears, and until now it looked like new CEO Emma Walmsley would follow suit and ignore claims that GSK’s parts are worth more than the whole".
It's a landmark day for GlaxoSmithKline, says its chief executive Emma Walmsley.
She is speaking to analysts after announcing a tie-up with Pfizer and plans to spin off the consumer heath care unit in three years.
She has been telling them about the unification of "category leading power brands" (shown above).
GSK's shares price are up 7%.
Drug giants GSK and Pfizer are combining their consumer healthcare businesses.
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GSK has told its shareholders that it intends to pay an unchanged dividend of 80p per share for 2019.
This is an attempt to show shareholders that its financial position will not be weakened by the deal with Pfizer's consumer health care division.
Its shareholders must vote through the deal which includes Pfizer products such as Advil painkillers and Centrum vitamins.
GSK will pay a break fee of $900m if the company changes its mind about the Pfizer deal or if the shareholders do not approve it by 30 September 2019.
Emma Walmsley, GSK's chief executive, said: "Through the combination of GSK and Pfizer's consumer healthcare businesses we will create substantial further value for shareholders".
More on the GSK/Pfizer deal.
Within three years of the closing of the transaction, GSK intends to list GSK Consumer Healthcare on the stock market.
Earlier this year, there were reports that the company was under pressure from investors to hive off this arm which owns products such as Panadol and Aquafresh.
Earlier this year GSK was in the running to buy Pfizer’s consumer healthcare business.
Now the two have embarked on creating a joint venture.
The companies say they expect annual cost savings of £500m by 2022.
They expect to sell off businesses to cover the costs of the integration.
GlaxoSmithKline and Pfizer are to combine their consumer health businesses to create a business with combined sales of £9.8bn.
GSK will have a 68% stake and Pfizer 32%.