FDA Phonetic and Orthographic Computer Analysis Program
fda.gov
fda.gov
"Automatic identification of confusable drug names" (2006, http://goo.gl/W5DK0f PDF)
and
"Identification of Confusable Drug Names: A New Approach and Evaluation Methodology" (2004, http://goo.gl/RziUgf PDF)
Both by Grzegorz Kondrak and Bonnie Dorr.
I've used the BI-SIM in a medical-informatics system and it does quite well. I'm also a big fan of EDITEX, which for some uses is better.
http://www.fda.gov/downloads/Drugs/DrugSafety/MedicationErro...
The PDF was previously submitted by 'aclimatt' here: