The Tottenham defender, currently with England on World Cup qualifying duty, was the subject of front page headlines on Sunday after photographs emerged of him taking the 'legal high' nitrous oxide - inhaling it from a balloon.
The incident took place in his native Sheffield during a night out this summer, and Walker was quick to issue a statement apologising.
"Apologies for not commenting sooner on a story about me today. I've been training and am focused on Tuesday's game for England," he said via his Twitter account.
"Now I know the health risks, it was poor judgement on my part.
"I won't be doing this again and hope that no one else is influenced into putting their health at risk by my actions."
Walker was named as the PFA's Young Player of the Year in 2012 and has won seven caps for England since making his debut against Spain in 2011.
The FA said that because his actions were not illegal, he will not face disciplinary action.
A statement from the FA read: "Kyle Walker has expressed his regret for an error of judgement when inhaling Nitrous Oxide earlier this year.
"The FA and the England manager have spoken to Kyle about the matter and he has assured us it will not happen again. Inhaling Nitrous Oxide is not illegal, but we recognise the associated dangers.
"Kyle has accepted this mistake. He will not face any action under the England Player Code of Conduct.
"The FA and England manager will not be making any further comment on this matter and will be focusing their full attention on Tuesday's match with Ukraine."
Given Walker is a certain starter in Kiev due to injuries to Glen Johnson and Phil Jones, Hodgson could have done without the distraction.
Yet it does raise questions over whether the players' code of conduct, announced last year amid much fanfare by former FA chairman David Bernstein, is going to be enforced as rigidly as initially expected.
For, whilst Walker has not broken any laws, it is difficult to see how his conduct was befitting of an England player.
"It's important to bear in mind that Kyle is a young lad," PFA deputy chief executive Bobby Barnes told Victoria Derbyshire on BBC Radio Five Live.
"Growing up in the public eye, not only will you see successes but you'll also see the mistakes that he's made.
"He is obviously very contrite about this.
"He's made a full apology and more importantly he's made it clear that he's aware of the dangers and he'll transmit that to other youngsters out there.
"The important thing to remember is that he hasn't committed a crime and it's not on the banned list.
"Having said that, it's something that's certainly not desirable for a footballer or a youngster to be doing."