(Bloomberg) -- Drugs from Novo Nordisk and Eli Lilly Co. are being investigated by the UK medicines regulator over patient reports of suicidal thoughts, shortly after Europe’s watchdog opened a probe into the same issue.

The UK Medicines & Healthcare products Regulatory Agency has received several reports of suspected adverse drug reactions associated with such behavior possibly related to semaglutide — the active ingredient in Novo’s diabetes and weight-loss drugs Ozempic and Wegovy, the agency said in a statement Wednesday. The MHRA has also received reports linked to liraglutide — the active ingredient in Saxenda.

The reports have sparked an investigation by the agency into all so-called GLP-1 drugs available in the UK, the MHRA said, including Sanofi’s lixisenatide, Eli Lilly’s dulaglutide, and a diabetes drug from AstraZeneca Plc, which uses the active ingredient exenatide.

We’re “reviewing safety data on the risk of suicidal thoughts and thoughts of self-harm associated with” the medicines, used to treat obesity and diabetes, Alison Cave, the MHRA’s chief safety officer, said in a statement. “We will carefully consider all available evidence and communicate any further advice.”

The MHRA contacted Novo earlier this week to request a review of cases possibly linking the drugs to thoughts of self-harm or suicide, the Danish drugmaker said in a statement. Spokespeople for Lilly, Astra and Sanofi didn’t immediately respond to requests for comment.

The MHRA investigation started July 12.

Novo shares fell 2.8% in Copenhagen, trading lower after Reuters initially reported on the UK review Wednesday. Lilly shares also fell 1.7% in New York.

The European Medicines Agency started looking at similar adverse events earlier this month after receiving reports from the Icelandic Medicines Agency related to Saxenda and Ozempic. Suicidal behavior is not currently listed as a side effect in the EU product information of the drugs.

--With assistance from Madison Muller and Naomi Kresge.

(Updates from first paragraph to include other drugs under investigation and the date the agency started its probe)

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