Adrian Mutu faced a possible two-year suspension on Monday after his agent Gheorghe Popescu said Chelsea had told him the striker had tested positive.
"Chelsea confirmed to me that Mutu had tested positive but did not reveal the substance. I realised that it concerned a drug, not a doping substance," Popsecu told Reuters from London.
"Chelsea said that the (drug) would not be disclosed under a confidentiality clause," added Popescu, who had flown to London with Victor Becali, who also acts for the player, to meet Chelsea coach Jose Mourinho.
Mutu had earlier in the day protested his innocence and Popescu, speaking to Romania's Radio Total, said: "Of course, Mutu is scared. His fate and his future are threatened.
"He has taken the news very bad. He's shocked but that is normal, it is normal to be shocked," Popescu said on arriving at Heathrow airport.
Popescu said Mutu had confirmed to him that a dope test had taken place at Chelsea's training camp in early October and said neither the club nor the British anti-doping agency had handed him the results.
Chelsea have not commented on the allegations after British newspapers reported in their first editions on Monday that Mutu had tested positive for cocaine.
Popescu said he had recommended to Mutu that he should not wait for a test of the B sample.
"I told him not to ask for the second sample so as not to prolong his agony. I told him that almost always the second sample confirms the first sample. He seemed not to understand what I told him."
Popescu added: "Mutu is destroyed. I told him to assume full responsibility for his actions but he seemed not to understand what it really means.
"We'll discuss his future after we see what Chelsea decide."
TORRID TIME
The 25-year-old Mutu has endured a torrid time at Stamford Bridge where he has fallen out with Mourinho after playing for Romania against club advice.
After returning to London from Bucharest last week Mutu was handed a hefty fine for making critical comments about his club coach.
When asked last week when Mutu, who is still officially listed as injured by Chelsea despite appearing for his country, would play again, Mourinho said: "At this moment I see that day as a long way off."
Mutu has been involved in several other incidents recently, including losing his driving licence for refusing to present his identity papers to police before Romania's World Cup qualifier against Finland in Bucharest in August.
Gordon Taylor, head of the English players' union, told Sky Sports News: "Things haven't been going well for him...it's not the peak of his career at the moment. It's a matter of some concern because any action will apply internationally as well."
