Page 97 - The lraternational Journal of the Royal Society of Thailand.indd

The International Journal of the Royal Society of Thailand
Volume XV-2023

as comorbidities, concurrent medication and potential drug interaction, cost, mood or
sleep disorders, fall risk, etc. Clinicians may assess patient preferences for effective
oral, topical, nontraditional, and nonpharmacologic interventions for PDN (ElSayed
et al, 2023; Ziegler et al,2021; Price et al, 2022).

Several groups of medications have been shown in clinical trials to aid in

relieving this debilitating pain condition. In many national and international guidelines,
gabapentinoids (such as gabapentin, pregabalin, mirogabalin), serotonin-norepinephrine
reuptake inhibitors (such as duloxetine, venlafaxine, desvelafaxine), tricyclic
antidepressants (such as amitriptyline, nortriptyline) are recommended as first-line
pharmacologic treatments for neuropathic pain in diabetes. The second-line medications

may include sodium channel blockers (such as oxcarbazepine, lamotrigine, lacosamide,
valproic acid), weak opioid (tramadol) and topical capsaicin preparations. Due to high
teratogenic potential from valproic acid in women of childbearing potential, clinicians

should not recommend valproic acid unless multiple other medications have failed
(Feldman et al, 2019 & Ziegler et al, 2022 & Ziegler et al, 2021; Price et al, 2022; Moisset
et al, 2020).

Strong opioids should not be used due to their potential serious side effects,
overdose and addition. Moreover, opioid use in non-malignant indication is strongly

related to higher risk of hospitalization and death from overdose. The use of opioid
along with sedatives, alcohol and some gabapentinoids may elevate this risk. The issue
of tolerance, misuse and dependence should be evaluated prior and during the
treatment. Regular evaluation should be performed at least every 3 months. Recent
guideline also discourages its use and highlight the need for safer medication (Price et

al, 2022; Moisset et al, 2020). For the past few years, cannabis has been increasingly
used for chronic non cancer pain, which includes neuropathic pain. Mild pain reduction
was seen in neuropathic pain trial, but the side effects may outweigh the benefit (Mücke

et al, 2018).
In patients preferring topical, nontraditional, or nonpharmacologic interventions,

providers may offer topical (capsaicin, glyceryl trinitrate spray, Citrullus colocynthis),
nontraditional (Ginkgo biloba) (Price et al, 2022) or nonpharmacologic interventions
(CBT, exercise, Tai Chi, mindfulness). Topical analgesic is an important alternative to

avoid systemic side effect. Lidocaine patch was recommended as second line treatment
, but it is not convenient to use in wide or ill-defined area. The potential of systemic
absorption is also a concern.

Capsaicin in a potent agonist of transient receptor potential vanilloid- 1. This
receptor is found at skin. Once this receptor is activated, the burning sensation will

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