Analgesia is pain relief eg NSAID

Anaesthesia is prevention of pain by the loss of sensation.

Nociceptive pain is from tissue damage eg postoperative pain and trauma.

Neuropathic pain is from nerves sensitised by sensory damage eg . Allodynia false signals are
interpreted as pain from nerves that do not normally carry pain signals, e.g. optic nerves.

 

NSAIDs reduce prostaglandins at the site of injury or inflammation. Prostaglandins sensitize nociceptors. The analgesic effect of NSAIDs occur at lower doses than are used to inhibit prostaglandins. NSAIDs are used to relieve nociceptive pain but may be used in neuropathic pain when it is not eased by conventional analgesics eg opoids

Local anaesthetic eye drops can slow healing
by decreasing the motility of the epithelial cells, and
normal epithelium may be damaged.
Oxybuprocaine and proxymetacaine
may cause epithelial keratitis and are toxic to the cornea.