In a classic case of David vs. Goliath, the Austrian startup Diagnosia, which provides apps for doctors and hospitals to help them quickly access drug information, is being sued by global pharmaceutical company Sanofi over how it lists the painkiller Metamizole.

Specifically, Sanofi is unhappy with the way the Diagnosia Enterprise app — so-called Evidence-based Drug Decision Support Software, which is designed to help physicians make the right medication decisions — classifies Metamizole and its possible side effects and how it might interact with other medication.

The big pharma company is seeking damages and that Diagnosia alert its customers of the allegedly false information. This originally included taking out an injunction against the startup at the end of last year, which Diagnosia successfully contested. The litigation remains ongoing.

“We are being sued for injurious falsehood (reputational and financial damage) for publishing certain side effects and drug interactions that possibly bear a risk for patients,” explains Diagnosia Medical Director and co-founder Lukas Zinnagl. “[It] is a strange claim. We are evidence-based, neutral and have in general no problem with Pharma.”

The case is also curious on a number of fronts. Firstly, although Metamizole was first introduced in Germany in 1921, the drug is not available in the U.S., Japan or Sweden due to known, albeit rare, side effects.

Secondly, and most puzzling, Diagnosia isn’t the only drug information database to place Metamizole in the NSAIDs drug group, for which I understand Sanofi is objecting, nor is it the only one to draw attention to research into possible side effects and interactions.

Diagnosia says that the so-called bible of drug interactions, Stockley’s drug interactions, and the U.S. drug information software Micromedex, and Switzerland’s MediQ, has similar information. In addition, the European Medicines Agency lists Metamzile in the NSAIDs group.

Lastly, Sanofi dwarfs Diagnosia in size and resources — 100,000 vs 15 employees respectively — so it could simply be a case of big pharma bullying a startup through the threat of litigation. However, Diagnosia is adamant that it has no need to change the way it lists Metamizole and vows to continue to fight the case.