> Does anyone know if Centrum Multivitamins contain lactose?  It's not
>> listed as an ingredient but can lactose be a filler and not get
>> listed?
>
>In vitamins, yes. Foods, no.<

It's true that the over-the-counter medications are subject 
only to voluntary disclosure of inactive ingredients. But as 
far as I know, when they do list inactive ingredients, they 
list all of them. 

It's always worth checking with the company, but I would 
guess that any symptoms are coming from dairy in the 
diet. The equivalent of 1 ounce of milk in food would contain 
more lactose than you would get in a hundred vitamin pills.