Wiggins applied for therapeutic use exemptions (TUEs) to take anti-inflammatory drug triamcinolone to help with his allergy and respiratory issues.
The 36-year-old is adamant that he gained no unfair advantage from the drug, which he says simply put him on a "level playing field" with others, but Froome admits that it is a difficult situation and questions will therefore continue to be asked.
"It's impossible to say if he was operating in a grey area," he told Cycling News. "I knew he had asthma, but I wasn't aware of his allergies.
"Questions remain over his symptoms, the choice of treatment and the related performance benefits from that treatment. It's a great shame for the sport that we're once again debating the validity of a Tour de France victory."
Wiggins, Great Britain's most decorated Olympian, took triamcinolone ahead of the 2011 and 2012 Tours and also before the 2013 Giro d'Italia.