Transdermal Lidocaine and Ketamine for Neuropathic Pain: A Study of Effectiveness and Tolerability

BACKGROUND Acute neuropathic pain is a common disorder. Transdermal cream could be an alternative to oral medications. OBJECTIVE To evaluate the effectiveness and tolerability of transdermal Lidocaine and Ketamine for acute neuropathic pain. STUDY DESIGN Retrospective chart review SETTING University-affiliated outpatient Physiatry clinic METHODS ARTICIPANTS: neuropathic pain with a prescription of a transdermal cream containing Lidocaine and Ketamine. Ef-fectiveness was evaluated by the number of patients with improvement divided by the total number of patients who re-ceived a prescription of the cream. RESULTS A total of 854 patient charts were reviewed. Twenty-one patients with symptoms, signs, and/or a documented di-agnosis of neuropathic pain and had been given a prescription of a transdermal preparation containing Lidocaine and Ketamine. Four groups were identified: those with a clearly stated diagnosis of neuropathic pain and prescribed a transdermal compound containing Lidocaine and Ketamine with follow-up (Group A) or without follow-up (Group B), and those with a suggested diagnosis of neuropathic pain with (Group C) or without follow-up (Group D). Effectiveness of the cream was seven out of eight (87%) for Group A and one out of three (33%) for Group C. In total, eight out of 11 patients (73%) benefited from a cream containing Lidocaine and Ketamine. Two patients experienced skin reactions that led to discontin-uation of treatment. LIMITATIONS This is a retrospective chart review without control group. CONCLUSION Transdermal cream containing Ketamine and Lidocaine was effective in 73% of patients with acute neuro-pathic pain and may be a good alternative to oral medications.