I Have 6 Weekly Injections Of Avastin Into One Eye.

I have 6 weekly injections of Avastin into one eye. I have awful problems after the injection due to the stinging and tearing for the rest of the day and night because of an adverse reaction to the Betadine used. They have flushed the eye afterwards but as soon as the numbing drops wear off I have terrible pain, and nausea. What can I suggest the doctor uses instead of Betadine.