Efficacy of addition magnesium sulphate or tramadol to potentiate the action of gabapentin in management of painful diabetic neuropathy

ABSTRACT

Diabetic neuropathic pain [DNP] is a chronic pain that persists for more than three months even after control the blood glucose level, and it resists the ordinary treatment as tricyclic antidepressants and carbamazole. It is usually due to extensive peripheral and spinal damage secondary to chronic hyperalgesia and release of glutamate neuromediator that acts on the NMDA receptors. The activation of N-methyl-D-asparate [NMDA] receptor is involved in the development of hypersensitivity states and it is known that gabapentin is anti-convulsant drug that recently has demonstrated its efficacy in management several types of neuropathic pain. It is known that magnesium physically blocks the N-methyl-D-aspartate receptors. Tramadol is analgesic agent that acts partially on opiate receptors and acts peripherally to activate the spinal descending inhibitory pathway. The aim of the present study is to evaluate the effects of adding oral magnesium sulphate or oral tramadol to potentiate the effects of oral gabapentin in management of painful diabetic neuropathic pain [DNP]. The study performed on 30 adult patients with sever DNP. Patients were divided into three equal groups. Group I patients received one tablet of gabapentin [Neuroton] 300 mg/TDS, group II patient received one tablet of gabapentin plus one tablet of magnesium sulphate [Biomag tab]/TDS, group III patients received one tablet of gabapentin plus one tablet tramadol [Tramal capsule] TDS. Patients received treatment for two weeks. The measurements included Pain, Emotion and Behavior changes assessed by Mc Gill Pain Questionnaire [MPQ], which is composed of Present Rating Index [PRI], Present Pain Index [PPI] and duration of pain. Therapeutic Efficacy Scale [TES]. Simple beside for allodynia and hyperalgesia. Modified Pittsburg Sleep Quality Index [MPSQI]. At the end of treatment there was significant decrease in pain score and comorbid condition associated with DNP and improvement in Modified Pittsburg Sleep Quality Index [MPSQI]. Also there were 5 patients in GI 6 patients in GII and 8 patients in GIII, respectively with excellent to good improvement. Somnolence and dizzness were the most common adverse effects observed in all three groups. The previous study concluded that oral gabapentin is significant in relieving diabetic neuropathic pain [DNP] and improving its comorbid conditions as emotional, behavioral changes and sleep pattern disturbances. The addition of oral tramadol to gabapentin significantly improved DNP and its comorbid conditions in a shorter duration than gabapentin alone, but addition of magnesium sulphate [MgSO[4]] tablets to gabapentin improved pain only more than gabapentin alone