Iatrogenic injuries due to intramuscular (IM) injection, although less frequently reported than before, are still common. The sciatic nerve is the most commonly injured nerve because of an IM injection owing to its large size and the buttock being a common injection site. Iatrogenic injury to the sciatic nerve resulting from a misplaced gluteal IM injection is a persistent problem worldwide affecting patients in economically rich and poor countries alike. The consequences of sciatic nerve injection injury (SNII) are potentially devastating and may result in serious neurological and medico-legal problems. A 68-year-old male presented with intractable neuropathic pain from SNII that occurred during gluteal IM injection of an analgesic for post-appendectomy pain. This chronic SNII pain did not improve despite his gradual recovery from weakness in the left foot. Partial improvement was seen following an external neurolysis, performed three months post-appendectomy. SNII is a preventable complication of gluteal IM injection. While the complete avoidance of gluteal IM injection is desirable, should need arise, the use of an appropriate administrative technique is recommended.