GABINDOL PLUS

INDICATIONS:

The most common cause of neuropathy worldwide is diabetes mellitus [1]. A neuropathy prevalence of 30% is reported in diabetic patients, estimating more than 50% could suffer from it during the course of the disease [2]. Painful diabetic neuropathy (PDN) is one of the most common causes of chronic pain. Chronic pain affects 30% of the United States (US) population and has high treatment costs, estimated approximately to be 650 billion dollars [3]. Chronic pain treatment requires a multidisciplinary intervention and, sometimes, use of multimodal treatments [3]. This situation has required using combination drugs as a treatment alternative, towards improving the patient prognosis.

There is evidence suggesting that more than half of chronic pain patients receive two or more analgesics, although evidence supporting most of these combinations is limited [4]. Even when efforts for developing new drugs have allowed new treatment options, searching for further alternatives, effective and safe, is necessary. Therefore, it is possible, through synergy between drugs with different mechanisms of action, to provide greater pain killing effects with less adverse events. Treatment of painful diabetic neuropathy (PDN) includes using of antidepressants, anticonvulsants (calcium channel blockers), and opioid drugs, among others. One of the main problems when using these drugs is adverse events (AE),

occasionally limiting the possibility to use drugs recommended in clinical trials [5]. Complex B vitamins, specifically thiamine (B1) and cyanocobalamin (B12), have been shown to be of clinical use in some painful diseases, derived from their effects on the central nervous system, synthesis, and secretion of serotonin in several brain areas [6], blocking metabolic pathways related to oxidative stress [7], as well as their effects on the nitric oxide/guanosine monophosphate cyclic (NO/GMPc) pathway [8], among other mechanisms. Synergy of these vitamins with other drugs, for example, gabapentin, allows for reducing recommended doses of these vitamins as monotherapy, achieving greater reduction effects on pain intensity with less AE occurrence. Gabapentin (GBP), a calcium channel a2𝛿 ligand, has proven useful in the treatment of neuropathic pain, with effective results on a daily dosage interval of 1800– 3600 mg, although this doses are related to a higher AE rate (nausea, vomit, dizziness, and somnolence of 20–50%) [9]. Pregabalin (PGB), another calcium channel a2𝛿 ligand, has also shown benefit in the treatment of neuropathic pain, although such benefits are related to high doses, which are evidently associated with AE occurrence, including dizziness, somnolence, and peripheral edema[10]. Our study objective was to determine the efficacy of gabapentin/vitamins B1 and B12 (GBP/B1/B12) versus pregabalin (PGB) for painful diabetic neuropathy (PDN) during 12 weeks of treatment.