The former Springbok tested positive on 7 February for banned substance hydrochlorothiazide.

At a hearing conducted by the independent national anti-doping panel, Johnson said he had mistakenly taken his wife’s fat burner ‘The Secret’ rather than his own legitimate supplement ‘Nutrilean’.

Having considered various submissions, the hearing concluded that Johnson acted without intent.

It therefore found there was ‘no significant fault or negligence’ on his part and decided six months to be an appropriate period of ineligibility.

Due to the player’s timely admission and his conduct during the investigation, it was deemed that the ban should be backdated to 7 February, making him eligible again from 6 August.

Under World Rugby regulation 21.10.12.2 Johnson is permitted to fully resume training with his club with immediate effect.

‘I was horrified when I got the test results and once we tracked back and worked out I had inadvertently taken the wrong tablet,’ said Johnson.

‘I completely accept that I am responsible for everything in my body. Drug use is not something I would ever condone, and from now on I will be extra vigilant at all times.

‘I would like to thank my family and friends, everyone at Wasps, the RPA and our fans for their support through this difficult period and apologise unreservedly for what has happened.

‘I am now working hard in pre-season and am looking forward to putting this behind me and getting back to being part of the Wasps squad.’