it depends on the antibiotic and whether or not the multivitamin contains minerals like calcium iron or magnesium. certain antibiotics like tetracyclines fluoroquinolones (cipro and levaquin) and zithromax should be spaced apart from mineral supplements and antacids. call your pharmacist who can provide you with the correct advice for the specific antibiotic and multivitamin you are asking about.
can you take an antibiotic and a multivitamin at the same time or do you need to space them apart?