At a disciplinary hearing in Manchester on Thursday, Piper, 35, pleaded guilty to a charge of failing a doping control test on April 14, 2005 when he provided a sample which contained a cannabis derivative.
However, an ECB statement said: " At Piper's request sentence was adjourned until May 26, 2005. In the interim Piper is suspended from participation in all cricket under the jurisdiction of the ECB."
"The ECB will be making no further comment on this case at present."
Piper had already been suspended by Warwickshire on Monday pending the outcome of his ECB hearing.
Back in 1997 Piper failed an in-house drugs test for which he served a one-match ban.
His fellow Warwickshire players Paul Smith, now retired, and Graham Wagg have also served drugs-related bans.
Last season Wagg was given a 15-month ban by the ECB after testing positive for cocaine and, as a consequence, saw Warwickshire terminate his contract.