You are seeing a 30-year-old female in a primary care setting who has presented with a burning pain in the site that she previously had shingles several weeks ago. On examination you note hyperalgesia to a pinprick sensation in the dermatome, which was previously affected by shingles. She informs you that she has been taking paracetamol which has not helped the pain. What is the most next most appropriate treatment to start this patient on?