UK Athletics is facing calls for an inquiry into how much influence the banned coach Alberto Salazar, who mentored Mo Farah for more than six years, has had on athletes in its endurance programme.

The move comes after the US Anti-Doping Agency, who sanctioned Salazar on Tuesday for “orchestrating and facilitating prohibited doping conduct” while working with the Nike Oregon Project, said it also had serious concerns about his use of prescription medications on otherwise healthy athletes.

One of those is thyroxin, which UK Anti-Doping believes should be banned in elite sport because it has concerns over potential health risks for heart, skeletal muscle, bones, and metabolic pathways, and is now the subject of a Wada critical review.

Sebastian Coe orders athletes to sever all links with Alberto Salazar Read more

According to the Times, one leading British coach in Doha has written to the UKA hierarchy calling for an investigation into whether such methods were ever employed by staff in charge of the British Athletics team. On Wednesday the Guardian spoke to two elite GB athletes who shared the coach’s concerns.

UKA has declined to comment, but before Salazar’s ban its performance director, Neil Black, called him a “genius” and described his relationship with him as one of “total trust, total belief, total respect”.

Travis Tygart, the Usada chief executive, has said that athletes under Salazar’s wing were often kept in the dark about the substances they were given and used as “laboratory animals”. Tygart told the German TV channel ZDF: “You must understand that the athletes really had no idea what was going on with them, what was being given to them. What dosage, whether the methods were forbidden or not, they didn’t even know.

“An athlete was even told she needed medication for a myoma [a tumour of the uterus], even though she didn’t have a myoma at all. They lied to the athletes and did their medical experiments on them in the NOP. They were simply sent to the doctor and told they must listen to and trust him.”

Tygart confirmed that 10 athletes from the Oregon Project had helped Usada investigators. “All of them provided us with their medical evaluations. We found out they were fake and false information was added after we officially requested it.

“I hope Nike now sees this as a wake-up call. They can’t find any excuses any more, they have to admit that experiments were done on athletes in their name and on their premises, and that was just wrong.”

Salazar, who was stripped of his world championships accreditation, continues to deny any wrongdoing and has vowed to appeal. Nike has also backed the coach and said that his four-year ban “had nothing to do with administering banned substances to any Oregon Project athlete”.