Ancient Egyptian Medicine refers to the practices of healing common in Ancient Egypt from circa 3300 BC until the Persian invasion of 525 BC. This medicine was highly advanced for the time, and included simple, non-invasive surgery, setting of bones and an extensive set of pharmacopoeia and magical spells. While ancient Egyptian remedies are often characterized in modern culture by magical incantations and dubious ingredients, research in Biomedical Egyptology shows they were often effective and sixty-seven percent of the known formulae complied with the 1973 British Pharmaceutical Codex, aside from sterilization. Medical texts specified specific steps of examination, diagnosis, prognosis and treatments that were often rational and appropriate.