The forecast comes after Novo received results from China's Volume Based Procurement (VBP) tender, which covers insulin sold at Chinese hospitals.
"Novo Nordisk currently expects an estimated negative impact on global sales growth of around 3% in 2022 as a result of reduced prices and reduced volumes of insulin sold in China," it said in a statement.
Novo shares were down 2% at 1012 GMT on the Copenhagen blue chip index, which was down 1.1%, after earlier falling by nearly 5%.
"By agreeing to lower prices for insulin in China, Novo now has to find out how they can sell more of their innovative products," Sydbank analyst Soren Lontoft Hansen said, adding that Novo's new forecast was a bit less negative than expected.
Novo's sales in China of its new, innovative GLP-1 drugs, used to treat diabetes and obesity, rose 64% in the first nine months of 2021, even though Novo has lost market share within that product segment.
Insulin accounts for 75% of Novo's sales in China, a market that accounts for 12% of Novo's total sales.
"It is not a very big sensation that the turnover in China is under pressure," Nordnet analyst Per Hansen said in a note.
Novo will provide a financial outlook for 2022 when announcing full-year results on Feb 2.
(Reporting by Nikolaj Skydsgaard, additional reporting by Jacob Gronholt-Pedersen; Editing by Edmund Blair and Alexander Smith)