Can you OD on vitamins?

I don't know if this is a really stupid question. So after TTC for 3+ years, I have finally gotten my husband to take vitamins (gummies, but I'll take what I can get). So last night I hand him one of the bottles, a multi vitamin for him, and told him to take 2, as directed, while I opened another bottle, coq10, to get one out for him. He takes 2 of the multi vitamins, then take a like 3 or 4 more, because he likes gummies and wants to eat them like candy. I couldn't believe it. Like, you are are grown ass man and take about 3 times the dosage of a vitamin because you want some gummies. Go to the store and buy a box of fruit snacks!

I told him from now on I'm going to be giving him his vitamins when I take my medicine. Not only am I worried for his health, if it's unsafe to take that many, but vitamins aren't cheap! Not to be eating them as a little snack at least. This bottle was like $25 for a 1 month supply.