UA Physician-Researchers Specializing in Chronic Pain Help Patients Discontinue Use of Potentially Addictive Prescription Drugs

University of Arizona Health Sciences pain specialists are offering patients effective treatments for chronic pain, most often without prescribing drugs, such as Percocet, Oxycontin and other opioid-based medications that when used over a long period of time could lead to addiction.

In several cases, patients whose pain rendered them unable to work have been able to resume working.

Dr. Mohab Ibrahim and Dr. Amol Patwardhan Mohab Ibrahim, MD, PhD, and Amol Patwardhan, MD, PhD, both assistant professors in the UA College of Medicine – Tucson Departments of Anesthesiology and Pharmacology, are the doctors who direct the Chronic Pain Management Clinic, an outpatient clinic at Banner – University Medical Center South.

“Pain clinics nationwide are under-utilized,” Dr. Mohab said. “Patients think pain clinics are simply a place to go for prescription medications. Our program offers a full range of diagnostic services and advanced therapies to alleviate pain and improve physical functioning.”

One example is the spinal cord stimulator, a small, implantable device that resembles a heart pacemaker, and sends electrical signals to the brain to block the sensation of pain.

Drs. Ibrahim and Patwardhan are members of the Arizona Pain Research Group, led by Frank Porreca, PhD, UA professor of anesthesiology and pharmacology, who is known for his pioneering research on the molecular origins of chronic pain, and discoveries that may lead to new treatments.

Chronic pain – defined as pain lasting more than 12 weeks, or longer than expected – has been grabbing headlines in recent years.

  • The National Institutes of Health issued a report in January stating that 100 million Americans, roughly one in three, suffer from chronic pain. That means chronic pain affects more Americans than diabetes, cancer and heart disease combined, according to the American Academy of Pain Medicine.
  • A 2011 report from the National Academy of Medicine determined chronic pain costs the United States as much as $635 billion annually in health-care costs and lost productivity.
  • The U.S. Centers for Disease Control and Prevention identified overuse and abuse of opioid painkillers as a major public health problem that kills nearly 15,000 Americans each year.

Drs. Porreca, Patwardhan and Ibrahim are quick to point out that opioid drugs not only are safe, but necessary for patients with chronic pain related to cancer, surgery and severe trauma. But whenever possible, patients who visit the Chronic Pain Management Clinic will be offered non-opiate solutions to their pain.

In addition to the spinal cord stimulator, another treatment offered at the clinic is a medication called Dronabinol, a non-addictive drug developed and FDA-approved to control chemotherapy-induced nausea and vomiting, and to increase appetite for patients with AIDS. But more recently, it’s been used to help some patients with back pain, migraine or other chronic pain. Dronabinol is a “synthetic cannabinoid” that contains the active chemical in marijuana that dampens pain – and when used at appropriate doses, it can reduce pain without making the patient “high” or causing any of the other effects associated with smoking marijuana. Nor is it the same as “medical marijuana.”

Dronabinol has been life-changing for Thomas Page, 59, who suffered severe pain on his entire left side following a stroke in 2011.  “It’s gotten me away from opiates. I only take them once in a while,” said Page, who has been seeing Dr. Patwardhan since January. “I’m very grateful to him. He is compassionate and he explains everything so you can understand it. I’ve seen a lot of doctors, and seeing him has been the best experience ever in a clinical setting.”

The comprehensive pain clinic offers patients several other procedures to help reduce pain, including epidural injections of steroids, joint injections, high temperature and pulse radiofrequency ablations, spinal cord and peripheral nerve stimulators and Botox injections for migraine and other painful conditions.

Developing improved therapies for chronic pain has been Dr. Porreca’s goal since the early 1990s. Much of his research has been in collaboration with chemistry and biochemistry Professor Emeritus Victor Hruby, PhD, through an NIH program project grant that has been continuously funded for 23 years, and is currently up for renewal. Their work has focused largely on endogenous pain modulatory mechanisms that shape the human experience of pain.

“And that’s been very fruitful for us,” Dr. Porreca said, because it turns out that endogenous opioids and their receptors are in the brain and are fundamental transmitter systems essential to the experience of pain to its modulation by context, experience, memories and interpretation. “Ultimately, what Drs. Patwardhan and Ibrahim do is to engage those same brain circuits. So that’s the driving force of our work.”

Dr. Porreca describes as “revolutionary” the increased understanding of pain since the early 1990s. “What has been lagging is the introduction of new molecules that can lead to new treatments. But there are efforts and ongoing trials that can hopefully lead to some success.”

When new patients come to the clinic, Dr. Ibrahim said, “We will evaluate their situation, give our honest opinion and offer certain options. We like to see patients early on, rather than after they’ve tried months of different medications. Our main goal is to get the patient functioning again. And the majority do get better.”

About Dr. Ibrahim

Mohab Ibrahim, MD, PhD, came to Tucson from his native Egypt in 1993 with the intent of becoming a physician. At the UA he earned a bachelor’s degree in biochemistry and a master’s degree and PhD in pharmacology and toxicology. He graduated from the UA College of Medicine – Tucson in 2008, then completed a surgical internship at the UA and did his residency in anesthesiology at Brigham and Women’s Hospital in Boston. He followed that with a clinical pain fellowship at Massachusetts General Hospital.

About Dr. Patwardhan

Amol Patwardhan, MD, PhD, studied pharmacology and toxicology in his native India, where he also earned his MD. After receiving his PhD in pharmacology from the University of Texas Health Science Center in San Antonio, he completed his internship in surgery and his residency in anesthesiology at the UA, followed by a pain medicine fellowship with the anesthesiology program at the University of California, San Diego.

About Dr. Porreca

Frank Porreca, PhD, professor of pharmacology and anesthesiology, is a member of the UA Cancer Center and principal investigator of the UA Pain Research Group. He has served as editor-in-chief of Life Sciences, and as pharmacology section editor for Pain, and has authored more than 450 peer-reviewed papers providing insight into pain mechanism and treatment.  He is founder and scientific organizer of the Pain Mechanisms and Therapeutics Conference, a biennial event that attracts world-renowned members of academia and industry.

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Originally Posted: 
Tuesday, November 17, 2015 - 3:47am