Gifts that drug makers have long showered on doctors will be banned from pharmaceutical marketing campaigns under new voluntary guidelines titled the "Code on Interactions with Health Care Professionals." The guidelines will ask the chief executives of large drug makers to certify in writing that "they have policies and procedures in place to foster compliance with the code." The code, however, provides no definite limits on the millions of dollars spent on speaking and consulting arrangements that drug makers have forged with doctors. The code was written by the Pharmaceutical Research and Manufacturers of America.