THE HAGUE, March 13  A top toxicologist in the Netherlands said Monday that he believed that Slobodan Milosevic, the former Yugoslav leader, had been manipulating medication to fake a medical condition, a ploy that contributed to his ill heath and may have played a role in the heart attack that caused his death.  That theory was advanced by Dr. Donald Uges, professor of clinical and forensic toxicology at the University of Groningen, who suggested that Mr. Milosevic had been seeking to demonstrate that Dutch doctors could not cure him and that he should therefore be allowed to seek treatment, and freedom, in Moscow.  He was imprisoned here on charges of war crimes and crimes against humanity, including genocide during three Balkan wars in the 1990's.  Dr. Uges based his theory on his detection in Mr. Milosevic's blood of a drug that had not been prescribed for him and that was not only inappropriate but, under the circumstances, dangerous. Mr. Milosevic, who had complained days before that he was being poisoned, was found dead on his bed in his prison cell on Saturday morning.  The drug at issue is a powerful antibiotic known as rifampicin, used to treat serious bacterial infections like tuberculosis, leprosy and Legionnaire's disease. Rifampicin, detected in Mr. Milosevic's blood as recently as two weeks ago, is known to interfere with medications he was taking for high blood pressure.  An international team of doctors, including Dutch, Belgian and Serbian forensic specialists, attended an autopsy on Sunday and said in a preliminary report that Mr. Milosevic had died of a heart attack. Their toxicology tests are due in the next few days.  But experts from Moscow want to examine the results and perform their own autopsy in the belief that the previous one was inconclusive or erroneous, a plan that could delay Milosevic family plans to take the body to Belgrade for burial.  Other investigations are still going on. The Dutch police and the United Nations tribunal where Mr. Milosevic was on trial for four years are carrying on their own investigations into his abrupt death.  The discovery of the antibiotic in Mr. Milosevic's blood has raised a number of questions, including who brought it into prison and how it ended up in Mr. Milosevic's system.  The Dutch police have searched for clues in the three rooms most used by Mr. Milosevic: his private cell, the small room he used as his office, and the room where he received visitors. They are also investigating the source of the drug, which is difficult to obtain in the Netherlands.  All physicians treating Mr. Milosevic have reported that they never prescribed rifampicin for him, confidential court documents show.  Dr. Uges, in a 90-minute telephone interview on Monday, said he was first contacted in January by a senior toxicologist in The Hague, Dr. Daan Touw, who had been consulted by the court about Mr. Milosevic recurrent health problems.  "Milosevic had constant high blood pressure, and the cocktail that always works was having no effect," Dr. Uges said. "So Touw had concluded that another medicine was being used to stimulate the liver and to neutralize this cocktail. He asked me for a report, a counter-expertise, because his own report had been dismissed by Milosevic's lawyers."  "We both had the idea there was an unknown drug which broke down his own medication, and we got the idea that the most efficient was rifampicin," he said. "I wrote a report about this in January, which was sent to the court."  "In late February," he said, "I was asked to check a blood sample for rifampicin and found it," he said, adding that he was told only later that it belonged to Mr. Milosevic.  Dr. Uges said it was an unusual test. "Normally when you screen for toxic drugs you never screen for rifampicin because it is specific for tuberculosis and leprosy, so unless you have a reason, you don't look for it," he said.  The side effect of the antibiotic, he said, is that it activates the enzymes in the liver, so his blood pressure drugs would be quickly broken down, keeping his pressure high.  As he tried to make sense of the drug's use, he said, he learned that Mr. Milosevic had been insisting on going to Moscow for treatment.
A toxicologist said that he believed Slobodan Milosevic may have sought to fake an illness by manipulating medication.