The Advertising Standards Authority (ASA) is investigating claims made in an advert for Nurofen Express, after receiving a number of complaints.
Yesterday, a court in Australia ruled that Nurofen's products should be stripped from the shelves after finding there were no differences between products marketed for specific pain like migraines or back pain.
Nurofen Express claims to target the "real source of most headaches faster". The ASA is investigating if the company is misleading consumers through the advert.
The ASA received 12 complaints over the advert in February before launching its own investigation in March.
The Authority said: "Complainants have challenged whether the ad is misleading because it implies that the product directly targets muscles in the head. They've also challenged whether the claim 'gives you faster headache relief than standard paracetamol or ibuprofen' is misleading."
However, the ASA stressed that it only investigates markets of products, not individual products.