topiramate and Low-Back-Pain

Chronic lumbar radicular pain is the most common neuropathic pain syndrome. This was a double-blind, randomized, 2-period crossover trial of topiramate (50 to 400 mg) and diphenhydramine (6.25 to 50 mg) as active placebo to assess the efficacy of topiramate. Each period consisted of a 4-week escalation, a 2-week maintenance at the highest tolerated dose, and a 2-week taper. Main outcome was the mean daily leg pain score on a 0 to 10 scale during the maintenance period. Global pain relief was assessed on a 6-level category scale. In the 29 of 42 patients who completed the study, topiramate reduced leg pain by a mean of 19% (P = .065). Global pain relief scores were significantly better on topiramate (P < .005). Mean doses were topiramate 200 mg and diphenhydramine 40 mg. We concluded that topiramate treatment might reduce chronic sciatica in some patients but causes frequent side effects and dropouts. We would not recommend topiramate unless studies of alternative regimens showed a better therapeutic ratio.. The anticonvulsant topiramate might reduce chronic lumbar nerve root pain through effects such as blockade of voltage-gated sodium channels and AMPA/kainite glutamate receptors, modulation of voltage-gated calcium channels, and gamma-aminobutyric acid agonist-like effects.

Topics: Adult; Aged; Analgesics; Anticonvulsants; Chronic Disease; Cross-Over Studies; Diphenhydramine; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Female; Fructose; Humans; Intervertebral Disc Displacement; Ion Channels; Low Back Pain; Male; Middle Aged; Patient Compliance; Placebos; Radiculopathy; Receptors, Glutamate; Topiramate; Treatment Outcome

In the last decade, prescription of anticonvulsants for treatment of low back pain (LBP) increased 4-fold. Among them, topiramate has frequent side effects and a mechanism of action that is not fully understood. The authors describe a 65-year-old woman with dependence on topiramate prescribed for chronic LBP and discuss how she was successfully weaned off topiramate using duloxetine. A significant agonistic effect by topiramate on α-2 adrenergic receptors in the brain likely accounts for the symptoms of withdrawal that were seen. We attribute the resolution of her topiramate withdrawal symptoms to reduced norepinephrine (NE) release, a known effect of duloxetine administration.

Topics: Aged; Anticonvulsants; Duloxetine Hydrochloride; Female; Humans; Low Back Pain; Receptors, Adrenergic, alpha-2; Substance Withdrawal Syndrome; Topiramate; Treatment Outcome

The objective of this study was to demonstrate efficacy, benefit, and potential use of topiramate in treating obese patients with chronic low back pain. This is a case report from an outpatient academic pain multidisciplinary clinical center. The patient was a 30-year-old morbidly obese (body mass index [BMI]: 61.4 kg/m(2)) female suffering from chronic low back pain. With a known association between obesity and chronic low back pain, and a possible role of topiramate in treating both simultaneously, the patient was started on a therapeutic trial of topiramate. Over a period of a 12-week topiramate therapy, the patient experienced clinically meaningful and significant weight loss as well as improvement in her chronic low back pain and functionality. With more substantial evidence, pain physicians may start considering using topiramate in the multimodal management of obesity-related chronic low back pain based on their thoughtful consideration of the drug's efficacy and side effects and the patient's comorbidities and preferences.

Topics: Adult; Anti-Obesity Agents; Female; Fructose; Humans; Low Back Pain; Obesity, Morbid; Topiramate