Hi pammiex3,I am sorry that you are suffering with posterior blepharitis. Was this a diagnosis you arrived at with your own personal research or having you seen an ophthalmologist?I have seen a number cases of posterior blepharitis related to the application of homeopathic or herbal substances. Typically, this does resolve over time with cessation of the aggravating agent. Although, I have not seen olive oil specifically cause posterior blepharitis so this may have been a condition you would have developed regardless. If you have not already, I would recommend you see an ophthalmologist or oculoplastic surgeon in your area for a complete evaluation. Good luck and feel better!