Chronic pain can be very difficult to manage in many patients. Many of the traditional oral drugs used for pain treatment, such as opioids, NSAIDs, and anticonvulsants, can have unwanted systemic side effects. These classes of medications, among others, can be just as effective in managing pain when used topically. Using a multimodal approach to treating symptoms of chronic pain has also been shown to be efficacious, which can be easily accomplished using a topical formulation.
Classes of medications that can be used topically include: NSAIDs, Alpha II Agonists, AMPA-Na+ Channel Blockers, GABA Agonists, NMDA-Ca2+ Channel Blockers, Tricyclic Antidepressants.
Avoid first pass hepatic metabolism
Avoid GI tract
May improve compliance
Increased drug concentration at site of pain
Decreased systemic side effects
Most common side effect is rash
May not be suitable for large areas
Absorption may vary from patient to patient depending on the stratum corneum barrier