A patient will begin using a transdermal preparation of a muscarinic antagonist for overactive bladder (OAB). The nurse teaches the patient what to do if side effects occur. Which statement by the patient indicates the need for further teaching?

a."I can use sugar-free gum for dry mouth."
b."I may need laxatives for constipation."
c."I should keep the site covered to prevent other people from getting the medicine."
d."I will take Benadryl for any itching caused by a local reaction to the patch."