It’s well known that competition among pharmaceutical companies is fierce, and a misstep, usually in a clinical trial, can result in millions, if not billions of dollars lost. And now a glimpse of that competition is boiling over into the realm of television advertising.

In a case from April, made public by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) on Monday, Boehringer Ingelheim called on the MHRA to pull a television advertisement for Reckitt Benckiser’s over-the-counter (OTC) laxative Senokot (BI offers a competing OTC laxative known as Dulcolax) as it appeared to suggest the active ingredient in the drug was natural.

“We considered that the advertisement suggested that Senokot’s efficacy was due to the fact that its active ingredient was natural. In August 2014 MHRA upheld a complaint about a similar advertisement for Senokot that also suggested its efficacy was due to it being natural,” MHRA said.

Reckitt Benckiser has since withdrawn the advertisement (a 2012 version can be seen on YouTube), and MHRA warned the company that it “could be required to submit all promotional material for vetting should a similar advertisement be published in future.”

Meanwhile, from 1997 to 2014, Boehringer has been advertising its Dulcolax laxative on television as a “gentle” alternative. And the fight over the laxative advertising market seems to be getting even more competitive as just four days ago, Boehringer published two YouTube videos asking people on UK streets if they’re embarrassed “talking about poo.”

Unlike in the US, pharmaceutical companies in the UK can only advertise over-the-counter medicines licensed by the MHRA or the European Commission to the general public, while prescription medicines cannot be advertised to the general public, though companies can promote them to health professionals and others who prescribe or supply pharmaceuticals.

MHRA Decision: Promotion of Senokot by Reckitt Benckiser