(RxWiki News) When a medication doesn't work, it can be a real pain in the back — literally. A common medication for back pain may not be helpful to patients.
Pregabalin, which Pfizer sells under the brand name Lyrica, is often used to treat lower back pain. But a new study found that this medication did not relieve lower back pain in older patients.
The data showed that there was no difference in reported pain between patients taking pregabalin and those taking a placebo.
"Given the cost and potential side effects associated with pregabalin, it is critical that we understand the efficacy of this drug," said lead study author John D. Markman, MD, director of the Translational Pain Research Program at the University of Rochester in New York, in a press release. "This study convincingly demonstrates a lack of relief with pregabalin for the walking pain associated with lumbar spinal stenosis."
A total of 26 patients completed the study. All patients were older than 50 and had a confirmed case of lumbar spinal stenosis, which causes lower back pain.
The patients were randomly divided into two groups. One group took pregabalin first — then the placebo (fake pill) after a wash-out period. The other group took the placebo first and pregabalin after the wash-out period. A wash-out period is a set number of days in which a medication will be completely flushed out of the body.
Dr. Markman and colleagues measured when the patients first felt pain while walking on a treadmill. They also measured the level of pain felt at rest. Patients also reported their level of pain through surveys.
Overall, patients taking pregabalin and those taking the placebo felt their first signs of pain around the same time while walking. Pregabalin also didn't appear to ease back pain overall any more than the placebo.
The authors noted that the low dosage of pregabalin prescribed (300 milligrams) could have limited the study results. But higher doses may cause unwanted or risky side effects, Dr. Markman and colleagues said. For instance, the two most common side effects of pregabalin include dizziness and sleepiness. Other common side effects include dry mouth, swelling of the hands and feet, blurred vision, weight gain, trouble concentrating and feeling confused.
Also, the study period only lasted for 10 days. This duration could have been too short to allow the pregabalin to fully take effect, these researchers noted.
This study was published Jan. 20 in Neurology.
Pfizer funded this study. Most of the authors said they worked with Pfizer, as well as several other pharmaceutical companies, as consultants. Dr. Markman served on advisory boards for companies like Allergan and Pfizer. Amit K. Chowdhry and Drs. Jennifer S. Gewandter, Kate Czerniecka and Webster H. Pilcher, disclosed no conflict of interests.