How It Works
Experts do not know exactly how anticonvulsants work to reduce chronic pain. They may block the flow of pain signals from the central nervous system.
Why It Is Used
Anticonvulsant drugs typically are used to control seizures in people who have epilepsy. These drugs may also be used to treat other painful conditions, such as postherpetic neuralgia and fibromyalgia.
How Well It Works
Some anticonvulsant drugs may work better than others for certain conditions. Anticonvulsants seem to work best when they are used for nerve pain. Examples of nerve pain include postherpetic neuralgia and diabetic peripheral neuropathy.
About 7 out of 10 people with nerve pain who take carbamazepine have some relief from their pain, at least for a short time.1
Gabapentin helps about 3 to 4 out of 10 people who take it for nerve pain.2 Anticonvulsants can reduce some persistent low back pain.3
Pregabalin helps between 3 and 5 out of 10 people who take it for nerve pain, especially postherpetic neuralgia, diabetic peripheral neuropathy, and fibromyalgia.4
Gabapentin is sometimes used to treat chronic pelvic pain.5
Carbamazepine and oxcarbazepine are used to treat chronic pain from trigeminal neuralgia (sudden facial pain). The best evidence is for carbamazepine, but oxcarbazepine probably works well too.6
Common but temporary side effects may include dizziness, drowsiness, and fatigue. Tell your doctor if you think you are having side effects, which may include:
Do not suddenly stop taking an anticonvulsant. Your doctor will slowly reduce the dose of this medicine so that you won't have withdrawal symptoms such as anxiety, nausea, pain, sweating, and insomnia.
The U.S. Food and Drug Administration (FDA) has issued a warning on anticonvulsants and the risk of suicide and suicidal thoughts. The FDA does not recommend that people stop using these medicines. Instead, people who take anticonvulsant medicine should be watched closely for warning signs of suicide. People who take anticonvulsant medicine and who are worried about this side effect should talk with a doctor.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Medicine will be started in low doses and then slowly increased until it effectively reduces your chronic pain.
Anticonvulsants are not safe for everyone. To avoid side effects and complications, be sure to tell your doctor about all medical conditions you have and other medicines you are taking.
Anticonvulsants may increase the chance of birth defects. If you are pregnant or thinking of getting pregnant, talk to your doctor before taking medicines. Women who use topiramate during pregnancy have a slightly higher chance of having a baby with birth defects. If you are pregnant or planning to get pregnant, you and your doctor must weigh the risks of using this medicine against the risks of not treating your condition.
Complete the new medication information form (PDF)(What is a PDF document?) to help you understand this medication.
Wiffen PJ, et al. (2005). Carbamazepine for acute and chronic pain in adults. Cochrane Database of Systematic Reviews (3).
Moore RA, et al. (2014). Gabapentin for chronic neuropathic pain and fibromyalgia in adults. Cochrane Database of Systematic Reviews (4). DOI: 10.1002/14651858.CD007938.pub3. Accessed October 7, 2014.
Chou R, Huffman LH (2007). Medications for acute and chronic low back pain: A review of the evidence for an American Pain Society/American College of Physicians clinical practice guideline. Annals of Internal Medicine, 147(7): 505-514.
Moore RA, et al. (2009). Pregabalin for acute and chronic pain in adults. Cochrane Database of Systematic Reviews (3).
Engeler D, et al. (2012). Guidelines on Chronic Pelvic Pain. Arnhem, The Netherlands: European Association of Urology. Available online: http://www.uroweb.org/guidelines/online-guidelines.
Gronseth G, et al. (2008). Practice parameter: The diagnostic evaluation and treatment of trigeminal neuralgia (an evidence-based review): Report of the Quality Standards Subcommittee of the American Academy of Neurology and the European Federation of Neurological Societies. Neurology, 71(15): 1183-1190.
Primary Medical ReviewerAnne C. Poinier, MD - Internal Medicine
Specialist Medical ReviewerNancy Greenwald, MD - Physical Medicine and Rehabilitation
Current as ofMarch 12, 2014