When It Comes To Pain Relief, One Size Doesn't Fit All

When you get a headache or suffer joint pain, perhaps ibuprofen works to relieve your pain. Or maybe you take acetaminophen. Or aspirin. Researchers now confirm what many pain specialists and patients already knew: Pain relief differs from person to person.

Dr. Perry Fine is president of the American Academy of Pain Medicine. He also sees patients and conducts research at the University of Utah Pain Management Center.

It's all in the biology, says Fine. "Human beings, person to person to person, are very different in the way they respond to drugs, and one size does not fit all." In large part, that results from genetic differences in our pain receptors — the cells in our nervous system that recognize pain and transmit that message to the brain.

Just slight differences in the chemical nature of the drugs we use affect people differently, depending on their genetic makeup, says Fine.

In a massive review of current studies and research published earlier this month, scientists at Oxford University in England examined 350 different studies involving about 45,000 patients. They looked at doses of single painkillers as well as combinations of drugs, totaling 38 different pain medications — everything from acetaminophen, aspirin and ibuprofen to more powerful opiate derivatives.

Biochemist Andrew Moore headed the study, which aimed to explore whether one medication worked "best" for most people. Their conclusion: No. Certain pain medications which worked to relieve pain for certain individuals were barely noticeable for others.

It's a simple message for physicians, says Moore. "If the first painkiller a patient tries doesn't seem to be working, then a doctor should look to find an alternative reliable drug and see if it is more effective in that individual patient," he says.

Moore also found that combinations of medications often worked best, providing potent, long-lasting pain relief. Pain specialist Perry Fine says that coming up with effective pain treatment for patients is often a matter of trial and error. In the absence of genetic testing to predict a patient's response to a certain painkiller, the best option, he says, is to figure out a pain relief combination based on the patient's past experience in coping with pain.

But Fine offers this note of caution: More is not necessarily better, and certain high doses of individual medications as well as certain combinations of pain drugs can be toxic to the liver and kidneys. That's reason enough to check with your doctor first about safe doses and safe combinations of pain medications.

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