The Aged Care Commissioner's criticised a Balclutha resthome, where a 92-year-old resident was overdosed with fentanyl patches

A report reveals a GP at the Clutha Views resthome incorrectly prescribed a daily 50 microgram fentanyl pain relief patch - instead of every three days.

Staff also mismanaged replacing patches - and she was hospitalised after being found wearing two.

Commissioner Carolyn Cooper says staff repeatedly gave the incorrect dosage, and she identified systemic and organisational issues.

She's ordered an apology, and for this case to be used for staff education.