Topiramate in the Treatment of Sciatica

NCT00011804 | Completed Phase 2

• 2 other identifiers: 01010501-D-0105
• Study Type: interventional
• Target: 65
• Locations: 1 country
• Sites: 1

Brief Summary

This study will test the effectiveness of topiramate to treat pain caused by lumbar radiculopathy, or sciatica. Sciatica results from damage to the lumbar nerve roots, typically causing back pain and sharp, shooting pain down one or both legs. Although sciatica is common, there are no good treatments for it. Topiramate belongs to a group of medications commonly used to treat pain caused by nerve damage. Patients between 18 and 75 years of age who have had sciatica pain daily for at least 3 months may be eligible for this study. (This is taken from the first paragraph of the Qualification Criteria in the consent form. The inclusion criteria on page 6 of the protocol say "low back pain of 3 months duration or longer present at least 5 out of 7 days a week" and signs and symptoms of lumbar radiculopathy. Which is correct?) Participants will provide a medical history, as well as occupational and social information. They will undergo a standard neurological examination, including a test of cognitive (thinking) abilities, muscular function, reflexes and a sensory examination. The latter involves testing with a pin placed on the surface of the skin. Participants will also have routine blood tests and will fill out questionnaires on their daily functioning and psychological well being. Additional procedures may include magnetic resonance imaging (MRI) scans and possible referral to a psychiatrist for evaluation of depression or emotional difficulties. This "cross-over" study consists of two parts. In one part, patients will receive topiramate and in the other, an active placebo. An active placebo is a drug that does not work for the problem being studied but whose side effects are like those of the test drug. Diphenhydramine (Benadryl) is the active placebo used in this study. Diphenhydramine is an allergy medication with very mild side effects, such as drowsiness. During both parts of the study-topiramate and placebo-patients will keep a daily log in which they rate their pain, record other procedures they undergo, such as injections and manipulations, and record medication side effects. In the first week of the study, patients will remain on their current medications and record pain levels once a day. After the first week, they will begin taking the study drugs-either topiramate in increasing doses ranging from 50 to 400 mg. or diphenhydramine in doses ranging from 6.25 to 50 mg. The drug doses will be increased gradually over 4 weeks to minimize possible side effects. Increases will continue until the maximum tolerated dose is reached. Patients will continue on the highest tolerated dose for two weeks and then be tapered off gradually over 12 days. They will remain off drugs completely for a 2-day washout period and then begin the next treatment. Those who took topiramate for the first part will take diphenhydramine for the second part and vice versa. A study nurse will call patients twice a week throughout the study to check for problems and answer questions. A physician will see patients 6 weeks after the start of each treatment. During the last visit, at the end of the study, patients will repeat the questionnaires they filled out at the beginning of the study. Patients and their doctors will be informed of the medications that were effective in each individual's care.

Conditions

Sciatica

Keywords

Low Back Pain; Lumbar Radiculopathy; Anticonvulsants; Neuropathic Pain; Analgesia; Sciatica

Interventions

Topiramate DRUG

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Low back pain of 3 months duration or longer present at least 5 out of 7 days a week are eligible.
• Age between18-75 at the start of the study.
• Men and women of all ethnicities.
• Signs and symptoms of lumbar radiculopathy.
• Ability to understand the study measures and mentally capable of giving consent to participate in the study.
• Willingness to refrain from making changes in non-study medications taken for sciatica.
• Patients with failed back syndrome who satisfy the following criteria:
• Presence of low back pain and pain in one or both lower extremities (buttock and below) for 3 months or greater and at least one of the following:
• Sharp and shooting pain below the knee in one or both legs.
• Electromyographic evidence of 4th or 5th lumbar roots (L4 or L5) / first sacral root (S1) irritation on the affected side.
• Imaging (MRI or CT/Myelogram) evidence of nerve root compression in lower lumbar region on the affected side.
• Evidence of decreased/absent ankle reflex on the affected side.
• Evidence of weakness of muscles below the knee on the affected side.
• Evidence of sensory loss in L5/S1 distribution on the affected side.
• Pain level of at least 4/10 on average on a scale of 0 to 10 for the past month.

You may not qualify if:

• Hepatic and renal dysfunction (liver function tests: ALT/AST greater than 1.2 times upper limit of normal; Creatinine greater than 1.5 times upper limits of normal).
• Pregnancy or lactation.
• History of seizures.
• Presence of pain of greater intensity in any other location than the low back or the leg.
• History of narcotic abuse and/or drug or alcohol abuse in the past year.
• History of fibromyalgia.
• History of spinal unstability.
• Cognitive impairment such that the individual is unable to give informed consent, complete study data collection tools or required study visits.
• Unwillingness to use adequate contraception excluding oral contraceptive medications (such as barrier methods with spermacide simultaneously) for women.
• Presence of other medical condition presenting with numbness and pain in lower extremities, such as diabetic polyneuropathy and peripheral vascular disease.
• Allergy to topiramate.
• Participants must not use digoxin, probenicid, carbonic anhydrase inhibitors given their possible drug interaction with topiramate.
• History of nephrolithiasis.
• Allergy to diphenhydramine.
• History of narrow angle glaucoma.

Sponsors & Collaborators

• National Institute of Dental and Craniofacial Research (NIDCR): lead

Study Sites (1)

National Institute of Dental And Craniofacial Research (NIDCR)

Bethesda, Maryland, 20892, United States

Location

Related Publications (3)

• Watson CP. The treatment of neuropathic pain: antidepressants and opioids. Clin J Pain. 2000 Jun;16(2 Suppl):S49-55. doi: 10.1097/00002508-200006001-00009.

  PMID: 10870740 BACKGROUND

• Coderre TJ, Katz J, Vaccarino AL, Melzack R. Contribution of central neuroplasticity to pathological pain: review of clinical and experimental evidence. Pain. 1993 Mar;52(3):259-285. doi: 10.1016/0304-3959(93)90161-H.

  PMID: 7681556 BACKGROUND

• Bajwa ZH, Sami N, Warfield CA, Wootton J. Topiramate relieves refractory intercostal neuralgia. Neurology. 1999 Jun 10;52(9):1917. doi: 10.1212/wnl.52.9.1917. No abstract available.

  PMID: 10371550 BACKGROUND

MeSH Terms

Conditions

Sciatica; Low Back Pain; Radiculopathy; Neuralgia; Agnosia

Interventions

Topiramate

Condition Hierarchy (Ancestors)

Sciatic Neuropathy; Mononeuropathies; Peripheral Nervous System Diseases; Neuromuscular Diseases; Nervous System Diseases; Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Back Pain; Perceptual Disorders; Neurobehavioral Manifestations

Intervention Hierarchy (Ancestors)

Fructose; Hexoses; Monosaccharides; Sugars; Carbohydrates; Ketoses

Study Design

• Study Type: interventional
• Phase: phase 2
• Purpose: TREATMENT
• Sponsor Type: NIH

Study Record Dates

• First Submitted: February 28, 2001
• First Posted: March 1, 2001
• Study Start: February 1, 2001
• Study Completion: February 1, 2005
• Last Updated: March 4, 2008

Record last verified: 2005-02

Locations

US (1)