The blood samples of Rahul Mahajan, who was admitted to Apollo hospital on Friday in a critical condition, doesn't contain cocaine and any other drug, hospital officials said on Saturday.

• Maitra's autopsy suggests poisoning

The tests for all the toxic screens are negative, including that for cocaine and ecstasy, the officials said.

The tests were done for 14 drugs, they said adding, the doctors were not in a position to comment if he had taken any other drug, Dr Anupam Sibal of Apollo hospital told reporters.

Observing that when brought in, Rahul Mahajan was in a critical condition with "some kind of intoxication", Sibal said, "We cannot really say what it (ailment) was."

"We are unable to identify what caused the clinical situation," he said adding, all toxic screening done is negative and "we will not be able to say anything (if he has taken anything else) as tests are not available for everything."

He said there was "significant improvement" in Rahul's condition with all his vital organs liver, kidney functioning normally.

"His situation has improved. Blood pressure stablised. Urine output normal and oxygen status improved. He has been put on non-invasive ventilator," the doctor said.

Sibal said he (Rahul) was talking coherently, well-oriented and comfortable. "He asked for water," Sibal added.

Sibal said there was trace of alcohol in Rahul's body when he was brought to the hospital. "There was alcohol in his body, But it was very low," he said.

Asked whether the doctors tried to assertain what was inside Rahul's stomach, he said the tests for the same has been done by the Central Forensic Sciences Laboratory.

He said Rahul was "very sick" when he was brought to the hospital and in the last 24 hours the 31-year-old has shown "significant improvement".

Sibal declined to comment on what actiually triggered such a clinical situation and said the tests done at the Apollo Hospital were part of a standard medical protocol.

"It was dramatic. (But) we are unable to identify what happened. It is not our job. It is up to the investigative agencies to answer such querries," he said.

He said there was no signs of external injuries on Rahul or on the body of Maitra.

Asked whether the hospital authorities was under any pressure to cover up the case, Sibal said they were under no pressure.

"Our job is to take care of the patient. We have done that in a successful manner," he said.