The quick answer to the question above is probably not, unless you're taking Allegra on an empty stomach and only with water. You see, Allegra and fruit juice don't mix and neither does Allegra and most antacids.
Let me clarify though, there is no risk with taking Allegra with fruit juice. It is a very safe medication to take. But if you take it within 1 hour of drinking fruit juice or taking an antacid, then chances are, you're not getting the full effectiveness from your allergy medicine...

