Antidepressants & antiepileptic drugs for chronic non-cancer pain.

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Am Fam Physician. 2005 Feb 1;71(3):483-90.

Antidepressants and antiepileptic drugs for chronic non-cancer pain.

Maizels M, McCarberg B.

Department of Family Practice, Kaiser Permanente, Woodland Hills,

California 91365, USA.

The development of newer classes of antidepressants and second-

generation antiepileptic drugs has created unprecedented

opportunities for the treatment of chronic pain. These drugs modulate

pain transmission by interacting with specific neurotransmitters and

ion channels.

The actions of antidepressants and antiepileptic drugs differ in

neuropathic and non-neuropathic pain, and agents within each

medication class have varying degrees of efficacy.

Tricyclic antidepressants (e.g., amitriptyline, nortriptyline,

desipramine) and certain novel antidepressants (i.e., bupropion,

venlafaxine, duloxetine) are effective in the treatment of

neuropathic pain. The analgesic effect of these drugs is independent

of their antidepressant effect and appears strongest in agents with

mixed-receptor or predominantly noradrenergic activity, rather than

serotoninergic activity.

First-generation antiepileptic drugs (i.e., carbamazepine, phenytoin)

and second-generation antiepileptic drugs (e.g., gabapentin,

pregabalin) are effective in the treatment of neuropathic pain.

The efficacy of antidepressants and antiepileptic drugs in the

treatment of neuropathic pain is comparable; tolerability also is

comparable, but safety and side effect profiles differ. Tricyclic

antidepressants are the most cost-effective agents, but second-

generation antiepileptic drugs are associated with fewer safety

concerns in elderly patients.

Tricyclic antidepressants have documented (although limited) efficacy

in the treatment of fibromyalgia and chronic low back pain. Recent

evidence suggests that duloxetine and pregabalin have modest efficacy

in patients with fibromyalgia.