3.4.2 Anticonvulsants
Anticonvulsants are used to manage neuropathic pain, especially when the pain
is lancinating or burning. Phenytoin, carbamazepine, valproate, and clonazepam
suppress spontaneous neuronAl firing and are used to control lancinating pain
complicating nerve injury (Swerdlow, 1984). Dose-related transient bone marrow
suppression, which is associated with carbamazepine therapy (Horowitz,
Patwardhan, Marcus, 1988; Pellock, 1987), requires that it be used with caution
in cancer patients undergoing other marrow-suppressant therapies, such as
chemotherapy and radiation therapy. Toxicity often correlates with high
concentrations in serum, and levels in serum of phenytoin, valproate, and
carbamazepine should be monitored routinely (for example, monthly in the stable
patient). Systemically administered local anesthetic (intravenous lidocaine,
oral mexilitine, and tocanide) and antiarrhythmic agents have been used
clinically to treat neuropathic pain (Brose and Cousins, 1991; Dejgard,
Petersen, and Kastrup, 1988), although this is not currently an FDA-approved
indication for these drugs.
Transdermal
Nasal
Adjuvant Drugs
Corticosteroids
Antidepressants
Neuroleptic Agents
Antineoplastic Therapies
Intraspinal drug delivery systems
Index