My friend is having an allergic reaction to ursodiol. Is there another effective medication she can take? Our something to counter act it?

Very unlikely. Ursodiol gets it name from urso meaning bear. This is just another form of bile and allergic reactions are extremely unlikely. Ursodiol is mainly used to treat bile sludge and primary biliary cirrhosis. There is urso-forte alarger dose version of ursodiol. But there are no substitutes.
Anaphalactoid rxn. Some medications trigger reactions that have the same symptoms as a severe allergic reaction (anaphylaxis) but for which we can't identify an antibody to mediate the allergic response. Pretreatment with antihistamines & corticosteroids can ameliorate or prevent this reaction & is used for reactions to IV dyes. This would pose risk for someone who takes the drug daily like your friend.