The opioid crisis presents a need to consider alternative options for treating chronic pain. There is significant overlap in neuroanatomical circuits that process pain, emotions, and motivation. Neurotransmitters modulated by psychotropic medications are also involved in regulating the pain pathways.1,2 In light of this, psychotropics can be considered for treating chronic pain in certain patients. The Table1-3 outlines various uses and adverse effects of select psychotropic medications used to treat pain, as well as their psychiatric uses.
In addition to its psychiatric indications, the serotonin-norepinephrine reuptake inhibitor duloxetine is FDA-approved for treating fibromyalgia and diabetic neuropathic pain. It is often prescribed in the treatment of multiple pain disorders. Tricyclic antidepressants (TCAs) have the largest effect size in the treatment of neuropathic pain.2 Cyclobenzaprine is a TCA used to treat muscle spasms. Gabapentinoids (alpha-2 delta-1 calcium channel inhibition) are FDA-approved for treating postherpetic neuralgia, fibromyalgia, and diabetic neuropathy.1,2
Ketamine is an anesthetic with analgesic and antidepressant properties used as an IV infusion to manage several pain disorders.2 The alpha-2 adrenergic agonists tizanidine and clonidine are muscle relaxants2; the latter is used to treat attention-deficit/hyperactivity disorder and Tourette syndrome. Benzodiazepines (GABA-A agonists) are used for short-term treatment of anxiety disorders, insomnia, and muscle spasms.1,2 Baclofen (GABA-B receptor agonist) is used to treat spasticity.2 Medical cannabis (tetrahydrocannabinol/cannabidiol) is also gaining popularity for treating chronic pain and insomnia.1-3