The company was the first to introduce penicillin into the German market in the postwar period, after the Allied Control Council lifted its ban.

[1] Grünenthal became infamous in the 1950s and 1960s for the development and sale of the teratogenic drug thalidomide, marketed as the sleeping pill Contergan and promoted as a morning sickness preventive.

When the ban was lifted, Grünenthal was the first company to introduce penicillin in the postwar period into the German market.

[citation needed] Under its Head of Research Heinrich Mückter, a former Nazi scientist, Grünenthal synthesised thalidomide in 1954 and acquired a 20-year patent.

Soon after obtaining its patent in April 1954, the company started clinical trials, and from November 1956, marketed the drug for the treatment of respiratory infections under the trade name Grippex, a combination drug that contained thalidomide, quinine, vitamin C, phenacetin, and acetylsalicylic acid.

"[7] Around the world, more and more pharmaceutical companies started to produce and market the drug under license from Chemie Grünenthal.

[citation needed] In the US, representatives from Chemie Grünenthal initially approached Smith-Kline and French with a request to market and distribute the drug in North America.

However, the drug was distributed in large quantities for testing purposes after the American distributor and manufacturer Richardson-Merrell had applied for its approval in September, 1960.

The official in charge of the FDA, Frances Oldham Kelsey, did not rely on information from the company which did not include any test results.

Their son was born without arms, with hands growing from his shoulders, and their daughter suffered from a number of internal deformities.

The lawsuit alleged that Chemie Grünenthal was negligent in the testing of thalidomide and that they failed to warn of its effects on unborn children.

It was used in hindsight to strengthen the argument that doctors would interpret the word to mean that thalidomide was safe during the final stage of pregnancy only.

At the end of 2007, the British entrepreneur Nicholas Dobrik organised a group of victims and began an international campaign for further reparations.

[22] In July 2010, the British Prescription Medicines Code of Practice Authority (PMCPA) received complaints about a poster used by field-based teams at Grünenthal.

[26] Grünenthal developed the drug Tramadol, which is marketed under the brand name Tramal, one of the best-selling opioid painkillers.

[27] Current products include the birth control pill Belara and the matrix pain patch Transtec.

In 2018, Grünenthal acquired European rights to the pain-related[28] brands Nexium and Vimovo and the US-rights for Qutenza (capsaicin).