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"It has a metabolite that can accumulate that has some toxic effects on the brain," said Dr. Michael Wincor, USC Pharmacy and Medicine.
Dr. Wincor says Demerol suppresses respiratory function, reduces oxygen in the blood and lowers blood pressure.
"When you add all of these features together you can end up with someone who stops breathing and whose heart stops," said Dr. Wincor.
"It affects the nerve cells and muscle cells," said Cardiologist Dr. Robert Kloner, Good Samaritan Hospital.
Dr. Kloner says Demerol by itself is enough to cause physiological changes that could lead to cardiac arrest.
"It can cause a drop in blood pressure, what we call hypotension, and that can decrease the delivery of blood and oxygen to the heart muscle which can also cause a cardiac arrest. In addition Demerol can be associated with arrhythmias of the heart, where the heart beats irregularly, " said Dr. Kloner.
Both experts agree the potentially deadly side affects of Demerol are compounded when mixed with other painkillers such as OxyContin or anti-anxiety medications like Xanax.
"We start mixing any individual items from any of these categories and we end up with potentially lethal combinations. Mixing drugs that have brain depressant activity is always a very risky business," said Dr. Wincor.
Dr. Wincor says make sure you tell every doctor you see what types of drugs you're taking including over the counter supplements. He also says it's also good idea for people to get their prescriptions all filled at one drug store so that a pharmacist may be able to detect any potentially dangerous interactions.
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